Someone asked if it's the exhaust valve that drops first in a VF500 engine. The answer to that is apparently.
[image: IMG_3350.jpg]
[image: IMG_3351.jpg]
http://www.vfrdiscussion.com/forum/index.php/topic/76067-cornercarver-got-better-head-than-me/
Maybe I should go for three in a row :wacko:
Guess I'll just start taking everything apart. Anyone want a VF500C with clean title, but missing an engine?
Do you need your head back?
CornerCarverDo you need your head back?
Dunno yet. I have to sit down and do the cross-referencing of all the parts. I don't think I'll be able to sell it without an engine. Need to go through and make sure if I do a full teardown that I can get all the parts I need to rebuild. Should try and hand crank the engine over to see how the bore is first.
One main issue is that I think the head is scrap because the valve seat is too chewed up to be recut without really cutting a chunk of material off. The only good thing about that at all is the valves all look to be in pretty decent shape. The other spare head, the valves look pretty toasty.
The next step SHOULD be to take the VTR250 engine out and take the heads off of that so I know what all three problem engines have wrong with them. All three engines share enough parts.
The really scary thing is that I had this engine RUNNING for at least a minute before I realized that there was a serious problem and not a carb/fuel issue.
Wow...what a mess!
I was surprised to read how a significant number of these engines have suffered from the effects of broken valves. Back in "the day" (mid-to-late 80's) I was under the impression that the baby V-4s were pretty stout, as long as the engine's red line was respected. Camshaft wear issues were a problem for all of the 1st gen V-4s though.
I owned a '83 V65 Magna for a few years back in the 90's and enjoyed riding "the beast". I called her my "point and shoot" bike, for there was so much torque available it didn't matter much which gear you were in, if you pinned the throttle you'd better hang on. About 5 years after I sold my V65 I had an opportunity to try out a friend's 1st generation V-Max ('86). While Max's reputation for tire shredding acceleration when V-boost was active proved to be well deserved, I thought my old V-65 pulled harder at low revs.
My Dad purchased a '85 V-30 Magna w/just over 1k miles in 1990, and he only rode it another 6k miles before giving up on 2-wheeled transportation. Unfortunately my dad is 82 now and suffers from dementia. So barring a medical miracle he'll most likely spend his remaining days in the McGuire veteran's hospital where he's resided for the last 2 1/2 years.
About five years back he signed the title to his V-30 over to me in exchange for some work I did for him. By that time the little Magna had been stored unused inside his garage for over a decade-and it still sits there today. As I recall the little V-4 was a really nice engine with a smooth nature, & excellent carburation. She was surprisingly quick over 8k rpm, but didn't have much grunt down low in the rev band.
I'm hopeful that my dad prepped the little Magna well for the years of hibernation. I do know that he removed & drained the tank and I'm hopeful he did the same with the carburetors. I'm also hopeful that I'll be able to locate the (thankfully few) parts which he removed and failed to re-install over the years, including some of front brake and clutch components when I finally have the motivation and opportunity to attempt to hopefully coax her back to life.
Thankfully, I do know that she was well-maintained & not abused while my dad was still riding back in the 90's. So I'm hopeful the engine's internals s/b in much better shape than the images provided in this thread.
I just remembered that I borrowed the little Magna from my dad when I signed up to take the MSF Experienced Rider Course for the 1st time back in 1991. At the time (nearly a quarter century ago) one of the other students was on a Kawasaki's ZX10, which for a short time was top dog in the horsepower wars in those (pre ZX11) days.
Man, I feel old....
Edited November 22, 2013 by smoothsailinCornerCarverDo you need your head back?
Well, dunno lost my head long ago... :biggrin:
- I had a VF700 Sabre and it was a great bike when it wasnt being fixed. It had cam issues, cam chain problems, CCT crap. And finally a big metallic crack happened, and I yelled...... UNCLE! Pretty sure a valve let loose. Sold it cheap, and moved on.
--- Never will I touch a gen 1 bike again.
Damn, it was a sweet ride, but what a headache too.....
Adding a pic for grinssssss........
[image: Sabretonia1.jpg]
Maybe it's time to make it a custom build using a more reliable engine.
SEBSPEEDMaybe it's time to make it a custom build using a more reliable engine.
Let's assume that I have three bad engines (cause with the streak going, that VTR250 engine is going to be the same). The 250 is actually the easier one to deal with. Frame has no title, so I would probably just toss a CR250 motor in there and the CBR F1 front and rear on it for track day giggles. If I did get the 250 engine running, I would probably want to hunt down a titled frame for it and put it back on the street with the rest of the OEM parts (well, that front end still might have to go).
Now the 500's. What am I going to swap into a Magna frame? SV650? CBR500? Ninja 500? Possible, but probably loads more work than replacing a valve and piston. The 86 motor is actually in the hot seat now. Do I just crack that open and take a piston from it to put in the 500C, since that's the sellable bike? Or do I fix both of them and attempt to recoup something from the spare? Either of those two involves splitting the case, and both engines are pretty much in the same exact position, except the C has an entire bike with it while the F is just an engine.
I've never split an engine case before, but can't imagine it's anything super difficult. Need to read through the manual to see if there are any mandatory replacement parts that I can't get anymore. Piston, rings, con-rods, and rod bearings seem to be the big items that you can't get new. I did find someone with NOS pistons and rings. Maybe some more stuff.
I'll check and see if one of the pile of Honda V4s at the shop is a 500. you game to try another one?
timmythecopI'll check and see if one of the pile of Honda V4s at the shop is a 500. you game to try another one?
Brave souls....
:cool:
Back in their day, the little 500's were tough. I had an 86 VF500F and I bounced off the limiter quite often without incident. However, I have a feeling you will have issues with most VF500F/C engines going forward because of old tired valve springs. I doubt that you will find any NOS or aftermarket springs for them.
tbzepBack in their day, the little 500's were tough. I had an 86 VF500F and I bounced off the limiter quite often without incident. However, I have a feeling you will have issues with most VF500F/C engines going forward because of old tired valve springs. I doubt that you will find any NOS or aftermarket springs for them.
KPMI should have them as well. I should be able to get everything from them if I wanted to. $7 for OEM valve guides. That means a load of work and probably $400 in parts and labor minimum though.
The question is, why do the exhaust valves fail?
YoshiHNStbzepBack in their day, the little 500's were tough. I had an 86 VF500F and I bounced off the limiter quite often without incident. However, I have a feeling you will have issues with most VF500F/C engines going forward because of old tired valve springs. I doubt that you will find any NOS or aftermarket springs for them.
KPMI should have them as well. I should be able to get everything from them if I wanted to. $7 for OEM valve guides. That means a load of work and probably $400 in parts and labor minimum though.
The question is, why do the exhaust valves fail?
Because they are exhausted? :goofy:
I'm surprised the parts are still made for them. I thought I had read a few years ago that they weren't available any more.
pretty good explanation here:
http://www.motorcycleproject.com/motorcycle/text/v4_cams_what.html
I have a good running '86 VF500F engine. If interested, shoot me a PM.
Hey Creaky, could you shoot me a pm with some pics of your XR?
creakyI have a good running '86 VF500F engine. If interested, shoot me a PM.
Well, that's the issue, the 85 and 86 are different enough that I'm not sure they will swap. Well, they should swap into the frame no problem. I'll keep it in mind. I want to see what the VTR engine holds for me.
timmythecoppretty good explanation here:
http://www.motorcycleproject.com/motorcycle/text/v4_cams_what.html
That's a cool explanation on the cam problems, but the cams and followers look fine. The valve failed. So did the keepers fail? The spring wore out? Valve stretch? Perhaps just not keeping up with valve adjustments?
YoshiHNScreakyI have a good running '86 VF500F engine. If interested, shoot me a PM.
Well, that's the issue, the 85 and 86 are different enough that I'm not sure they will swap. Well, they should swap into the frame no problem. I'll keep it in mind. I want to see what the VTR engine holds for me.
timmythecoppretty good explanation here:
http://www.motorcycleproject.com/motorcycle/text/v4_cams_what.html
That's a cool explanation on the cam problems, but the cams and followers look fine. The valve failed. So did the keepers fail? The spring wore out? Valve stretch? Perhaps just not keeping up with valve adjustments?
I've read that the little Viffer's springs weaken over time and allow the valves to float or bounce.
tbzepI've read that the little Viffer's springs weaken over time and allow the valves to float or bounce.
If that's the case I should be able to measure that when I take the head apart.
Looking at the pics of youre engine, there is one thing wich set me thinking. The undamaged cilinder pair has soot on it, meaning a rich fuel mixture. The damaged pair has no soot and is completely burnt clean. Indicating a lean mixture, with a much hotter burning process. I have sean pics of complete piston meltdowns, ruining the complete engine, molten metal transferred troug the complete engine. Or the heat could cause high speed nock.
tbzepYoshiHNScreakyI have a good running '86 VF500F engine. If interested, shoot me a PM.
Well, that's the issue, the 85 and 86 are different enough that I'm not sure they will swap. Well, they should swap into the frame no problem. I'll keep it in mind. I want to see what the VTR engine holds for me.
timmythecoppretty good explanation here:
http://www.motorcycleproject.com/motorcycle/text/v4_cams_what.html
That's a cool explanation on the cam problems, but the cams and followers look fine. The valve failed. So did the keepers fail? The spring wore out? Valve stretch? Perhaps just not keeping up with valve adjustments?
I've read that the little Viffer's springs weaken over time and allow the valves to float or bounce.
+1 I have read it several times also ...
It was me that asked about which valve it was. I have a growing collection of pictures of blown VF500 engines. This one makes 8 and of those it can be said that in 7 of them, it is an exhaust valve that fails.
As to the why, I can only conclude it's just a marginal design. Of the picture I have where I can tell, the valve always seems to fail in the stem towards the head, almost in the radius of the valve head. However this might not be the root cause as I can also see examples where the head has broken off and the valve has failed in the keeper radius. I suspect in these examples the valve as failed in the keeper radius and then the impact of the valve on the piston has broken off the head.
On the plus side there are plenty of high mileage examples of VF500s still running so it isn't guaranteed the valves will fail this way. (I have one with 20K miles so mine ins't in this category yet). As a back up plan I have two spare engines. In Europe at least new valves and springs are unobtainium.
jeremyr62It was me that asked about which valve it was. I have a growing collection of pictures of blown VF500 engines. This one makes 8 and of those it can be said that in 7 of them, it is an exhaust valve that fails.
As to the why, I can only conclude it's just a marginal design. Of the picture I have where I can tell, the valve always seems to fail in the stem towards the head, almost in the radius of the valve head. However this might not be the root cause as I can also see examples where the head has broken off and the valve has failed in the keeper radius. I suspect in these examples the valve as failed in the keeper radius and then the impact of the valve on the piston has broken off the head.
On the plus side there are plenty of high mileage examples of VF500s still running so it isn't guaranteed the valves will fail this way. (I have one with 20K miles so mine ins't in this category yet). As a back up plan I have two spare engines. In Europe at least new valves and springs are unobtainium.
I tried to buy from CMSNL. They have a few springs and valves but not a full set of intake or exhaust. They may look like they do but they don't, or at least they ddn't in May this year when I ordered from them, even though their website suggested they did. They told me they were unobtainium too.
Strange because they listed them as in stock
Maybe i have a solution: I put the part number in Google and the same valve is used in the VTR 250 until 1990 and is still available at webshops in the US and Europe.
VFRBertMaybe i have a solution: I put the part number in Google and the same valve is used in the VTR 250 until 1990 and is still available at webshops in the US and Europe.
That was my original plan. To use the spare 86 engine as parts for my VTR and 85 VF engine rebuild. I am looking at options between parting out both engines and buying a third one, or rebuilding all three engines and selling the spare.
jeremyr62I tried to buy from CMSNL. They have a few springs and valves but not a full set of intake or exhaust. They may look like they do but they don't, or at least they ddn't in May this year when I ordered from them, even though their website suggested they did. They told me they were unobtainium too.
they are pricey, but if you want to spend the money, you could try these people. I was told that they did have the parts for the 500, but you will have to ask them. If I was doing a serious rebuild and had the money, I would seriously consider rebuilding my head with their parts. If they don't have them, maybe enough would want to rebuild their VF500 engines that the cost would be their normal levels.
http://valvetrain.kpmivalvetrain.com/category/honda-cbr-600-f2-f3-1991-to-1996
When I priced up the valves and springs and all the other bits and bobs, I decided it wasn't worth it and just kept on the look out on Ebay UK for a second hand engine. I found one eventually with 3,000 miles. Valves and cams look pristine. They are out there, you just have to be patient.
Unfortunately, all too common. The only way to prevent dropped valves on 500's is to keep those revs down. Observe a 9000rpm maximum engine speed and you'll enjoy a long life out of your VF500. Each time you exceed that you are one step closer to problems.
I forget were these engines unleaded gas or leaded gas only motors .
Unleaded, Japan was one of the first country's to introduce unleaded gas.
SwitchbladeI forget were these engines unleaded gas or leaded gas only motors .
I'm curious: why do you ask this question?
JamieDaughertyUnfortunately, all too common. The only way to prevent dropped valves on 500's is to keep those revs down. Observe a 9000rpm maximum engine speed and you'll enjoy a long life out of your VF500. Each time you exceed that you are one step closer to problems.
So that does sound like an issue with springs. I don't really have a need for a high performance mini V4, so not a worry. The 250 might be another story.
JamieDaughertySwitchbladeI forget were these engines unleaded gas or leaded gas only motors .
I'm curious: why do you ask this question?
The primary use of lead in gas was for valve cushioning ..
SwitchbladeJamieDaughertySwitchbladeI forget were these engines unleaded gas or leaded gas only motors .
I'm curious: why do you ask this question?
The primary use of lead in gas was for valve cushioning ..
yes, but to benefit the valve seats.
timmythecopSwitchbladeJamieDaughertySwitchbladeI forget were these engines unleaded gas or leaded gas only motors .
I'm curious: why do you ask this question?
The primary use of lead in gas was for valve cushioning ..
yes, but to benefit the valve seats.
Hmmm I wonder what the seats were being hammered by ?
I know the valves !!!!!!
No the lead in fuel was to stop valve seat recession caused by micro-welding on soft materials for valve seats - e.g. soft cast iron heads. See your local BMC mini or MG B for details. The lead works as a lubricant. As the Hondas have aluminium heads, Honda fitted hardened ferrous (iron-based) exhaust valve seats so that enable the bikes to run on Unleaded - because the materials used meant that valve seat recession was not an issue.
Dropped valves are usually caused by valve spring weakening, allowing the valve to bounce against the seat, weakening the narrowest part - the stem.
Does anyone if this is more or less likely in engines that have sat in the same position for a while (says he who owns a VF that was last registered on the road in 1994....) - an anecdotal story says that privateers with formula 1 engines used to have to turn the engines to a different position every day to avoid valve spring "set".
Edited November 29, 2013 by GazVF500Tetramethyl lead was added to gas to help make a cushion and seal between the valves and the valve seat ...
Use to be a SAE auto mechanic in the 80's, it was question on the test and I missed it, I answered octane booster...
how many miles were on the engine? and how were you riding when it ate itself??? the valves look dark ---rich like dirty air filter bad gas etc-- they should have a brown look to them those plugs never lie----
I not saying this is what caused Yoshi valve to unhead itself ..
VFRBertUnleaded, Japan was one of the first country's to introduce unleaded gas
I think it was the late 70's or early 80's, just could not remember ..
JamieDaughertyUnfortunately, all too common. The only way to prevent dropped valves on 500's is to keep those revs down. Observe a 9000rpm maximum engine speed and you'll enjoy a long life out of your VF500. Each time you exceed that you are one step closer to problems.
I enjoyed a long life in my 500 Belt-0-Ceptor and I exceeded 9K on just about every ride...
You're looking at 98,755 miles not in moderation...
[image: gallery_3131_51_36605.jpg]
SwitchbladeThe primary use of lead in gas was for valve cushioning ..
Negative... primary use of tetraethyl lead was for knock or detonation
control...
The story how lead got into our fuels started with high compression
aircraft engines back in 1921... a young engineer fresh out of college
named Charles Kettering started Dayton Engineering Labs Company or Delco...
he invented the first battery ignition systems for aircraft engines...
when protagonists in the field of aviation widely blamed his battery
ignition systems on knock or detonation Kettering commanded his young
assistant Thomas A. Midgley on a investigation of detonation.
motivated as much by a desire to protect Delco's reputation as by
scientific altruism. Midgley worked for months over his single
cylinder engine and famous "bouncing pin" which was devised to measure
differences in detonation pressures. and he soon determined that
detonation depended on both fuel grade and engine compression ratio.
Thinking at first that fuel color influenced knock. Midgley added
iodine to his fuel theorizing a dark-colored fuel would absorb more
heat energy and vaporize more quickly. When the knock diminished he
smelled success, but it did not come in the form . he suspected.
Further experiments forced him to discard the fuel color idea but led
in turn to a long. frustrating line of trial anti-knock additives. GM.
parent company of Delco. encouraged Midgley and his assistant T. A.
Boyd. who in a vigorous program, individually tested more than 30,000
compounds and their discouragement mounted with the list. On December
9, 1921. a chilly Friday. Midgley and Boyd were anticipating the
weekend's respite from their series of relentless, routine tests when
suddenly the engine was not behaving the same at all. Jolted into
disbelief, Midgley had quite literally stumbled onto the remarkable
antiknock properties of an obscure substance called tetraethyl lead.
This proved to be without doubt the greatest single discovery in the
development of aviation fuels; not only did this additive make higher
power possible. it enabled the aircraft to fly farther on a given
amount of fuel- it gave aircraft range and in turn enabled the
successful engines that dominated aviation until the advent of gas
turbines.
Thomas Midgley
[image: thomas-midgley-jr-12.jpeg]
Charles Kettering
[image: Time-magazine-cover-charles-kettering.jp]
Dearly beloved... we are gather here to pay our last respects to the passing of this sweet little VF500 engine...
[image: IMG_3350.jpg]
[image: IMG_3351.jpg]
I had a VF500 for 10 years, it got abused all the time, BUT I had a great maintenance regime. Fresh oil every 2500 miles, valve clearances every 5000 miles & it always needed it, plus oil & filter. It had over 65k miles when I sold it.
I suspect all these valve failures are due to loose valve clearances, allowing the valves to slam closed at high rpm, thus wearing the valve head. Or alternately over revving with worn or poorly maintained cam chains !
On the valve clearance issue, the screw wears from new to an angle & if you then adjust it, there is much less material in contact with the valve stem, so it wears much quicker after adjustment ! Buy a spare set of tappet screws & swap them when you do a valve adjustment, then face the old ones flat for reuse next time ! Valve adjustment stays good for longer ! Also lever the Y rocker up at its centre when measuring the clearances, to avoid any excess clearance from rock on the rocker shaft.
Good luck with the rebuild.
On a side note, Thomas Midgley contracted lead poisoning as a result of experimenting with TEL, and although debilitated, not die from it. He contracted polio at age 51 and was severely disabled as a result. He rigged a rope and pulley contraption over his bed to help lift him, got tangled up in the ropes one day and died of strangulation.
BusyLittleShopSwitchbladeThe primary use of lead in gas was for valve cushioning ..
Negative... primary use of tetraethyl lead was for knock or detonation
control...
The story how lead got into our fuels started with high compression
aircraft engines back in 1921... a young engineer fresh out of college
named Charles Kettering started Dayton Engineering Labs Company or Delco...
he invented the first battery ignition systems for aircraft engines...
when protagonists in the field of aviation widely blamed his battery
ignition systems on knock or detonation Kettering commanded his young
assistant Thomas A. Midgley on a investigation of detonation.
motivated as much by a desire to protect Delco's reputation as by
scientific altruism. Midgley worked for months over his single
cylinder engine and famous "bouncing pin" which was devised to measure
differences in detonation pressures. and he soon determined that
detonation depended on both fuel grade and engine compression ratio.
Thinking at first that fuel color influenced knock. Midgley added
iodine to his fuel theorizing a dark-colored fuel would absorb more
heat energy and vaporize more quickly. When the knock diminished he
smelled success, but it did not come in the form . he suspected.
Further experiments forced him to discard the fuel color idea but led
in turn to a long. frustrating line of trial anti-knock additives. GM.
parent company of Delco. encouraged Midgley and his assistant T. A.
Boyd. who in a vigorous program, individually tested more than 30,000
compounds and their discouragement mounted with the list. On December
9, 1921. a chilly Friday. Midgley and Boyd were anticipating the
weekend's respite from their series of relentless, routine tests when
suddenly the engine was not behaving the same at all. Jolted into
disbelief, Midgley had quite literally stumbled onto the remarkable
antiknock properties of an obscure substance called tetraethyl lead.
This proved to be without doubt the greatest single discovery in the
development of aviation fuels; not only did this additive make higher
power possible. it enabled the aircraft to fly farther on a given
amount of fuel- it gave aircraft range and in turn enabled the
successful engines that dominated aviation until the advent of gas
turbines.
Thomas Midgley
[image: thomas-midgley-jr-12.jpeg]
Charles Kettering
[image: Time-magazine-cover-charles-kettering.jp]
Double negative !!!
Tetraethyllead
From Wikipedia, the free encyclopedia Tetraethyllead [image: 200px-Tetraethyllead-Skeletal-SVG.svg.pn] [image: 180px-Tetraethyllead-3D-balls.png] IUPAC name[hide]Tetraethylplumbane
Other names[hide]Lead tetraethyl
Tetraethyl lead
Tetra-ethyl lead Identifiers Abbreviations TEL CAS number 78-00-2[image: 7px-Yes_check.svg.png]PubChem 6511 ChemSpider 6265[image: 7px-Yes_check.svg.png]UNII 13426ZWT6A[image: 7px-Yes_check.svg.png]EC number 201-075-4 UN number 1649 MeSH Tetraethyl+lead ChEBI CHEBI:30182[image: 7px-Yes_check.svg.png]RTECS number TP4550000 Beilstein Reference 3903146 Gmelin Reference 68951 Jmol-3D images Image 1 SMILES [show] InChI [show] Properties Molecular formula C8H20Pb Molar mass 323.44 g mol−1 Appearance Colorless liquid Density 1.653 g cm−3Melting point−136 °C, 137 K, -213 °F
Boiling point84-85 °C, 357-358 K, 183-185 °F (15 mmHg)
Refractive index (nD) 1.5198 Structure Molecular shape Tetrahedral Dipole moment 0 D Hazards EU classification [image: 40px-Hazard_TT.svg.png] T+[image: 40px-Hazard_N.svg.png] N R-phrases R61, R26/27/28, R33, R50/53,R62 S-phrases S53, S45, S60, S61 NFPA 704 [image: 75px-NFPA_704.svg.png] 2 3 3 Flash point 73 °C Related compounds Related compounds Tetraethylgermanium [image: 14px-Yes_check.svg.png](verify) (what is: [image: 10px-Yes_check.svg.png]/[image: 10px-X_mark.svg.png]?)Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox references
Tetraethyllead (common name tetraethyl lead), abbreviated TEL, is an organolead compound with the formula (CH3CH2)4Pb. It was mixed with gasoline (petrol) beginning in the 1920s as an inexpensive octane booster which allowed engine compression to be raised substantially, which in turn increased vehicle performance and fuel economy.[1][2] TEL was phased out starting in the US in the mid-1970s because of its neurotoxicity and its damaging effect on catalytic converters. It is still used as an additive in some grades ofaviation gasoline and automotive racing fuels. Innospec is the last firm still making TEL.
Contents [hide]Tetraethyl lead was extensively used as an additive to gasoline, wherein it served as an effective antiknock agent and prevented exhaust valve and seat wear.
Valve wear preventative[edit]Tetraethyl lead works as a buffer against microwelds forming between the hot exhaust valves and their seats.[3] Once these valves reopen, the microwelds pull apart and leave the valves with a rough surface that would abrade the seats, leading to valve recession. When lead began to be phased out of motor fuel, the automotive industry began specifying hardened valve seats and upgraded exhaust valve materials to prevent valve recession without lead.[4]
Antiknock agent[edit]A gasoline-fueled reciprocating engine requires fuel of sufficient octane rating to prevent uncontrolled combustion known as engine knocking ("knock" or "ping").[5] Antiknock agents allow the use of higher compression ratios for greater efficiency[6] and peak power. Adding varying amounts of TEL to gasoline allowed easy, inexpensive control of octane ratings; aviation spirits used in WWII reached 150 octane to enable supercharged engines such as the Rolls-Royce Merlin and Griffon to produce 1500 HP at altitude.[7] In military aviation, TEL manipulation allowed a range of different fuels to be tailored for particular flight conditions, and ease and safety of handling
Wikipedia is ALWAYS right .
Cushioning? Or prevents valve and seat burning by reducing microwelds?
I read it on the interwebs so it must be true! :wacko: :biggrin: :beer:
Edited November 30, 2013 by ajcmbrownThe vf500f is built for unleaded fuel, so that should not be a point of discussion.
1 thing is having my attention at al the pictures from broken pistons and cilinder heads. No black soot in the damaged cilinder, the cilinder and valves are burnt clean and have the browm color of rusted iron.
I think that cilinder was running on a very lean mixture, maybe caused by a leaking insulator. I have sean pics of cimilar damage on cbx550's, valve stressed to much by overheating, breaking and the we have an other serie of pics from a damaged engine.
i remember getting scolded in class because i said it was a fitting end for a man who caused so much death and suffering.
but like others have said.. have fun on the rebuild.. however. rebuild a non blown up motor. :tongue:
theelfhow many miles were on the engine? and how were you riding when it ate itself??? the valves look dark ---rich like dirty air filter bad gas etc-- they should have a brown look to them those plugs never lie----
What did I do? I bought the stupid thing.
MohawkOn the valve clearance issue, the screw wears from new to an angle & if you then adjust it, there is much less material in contact with the valve stem, so it wears much quicker after adjustment ! Buy a spare set of tappet screws & swap them when you do a valve adjustment, then face the old ones flat for reuse next time ! Valve adjustment stays good for longer ! Also lever the Y rocker up at its centre when measuring the clearances, to avoid any excess clearance from rock on the rocker shaft.
Good luck with the rebuild.
Good tip. I'll have to look at that closely for the rebuild.
MohawkFresh oil every 2500 miles
Whenever I see this it makes me shudder. The oil should be changed every 1000 miles, maybe 1500 max. Motorcycle oil is not the same as car oil, it is whooped at a fraction of the miles.
creakyOn a side note, Thomas Midgley contracted lead poisoning as a result of experimenting with TEL, and although debilitated, not die from it. He contracted polio at age 51 and was severely disabled as a result. He rigged a rope and pulley contraption over his bed to help lift him, got tangled up in the ropes one day and died of strangulation.
Well, aren't you just a little ray of sunshine? :goofy:
Veefer800CanuckcreakyOn a side note, Thomas Midgley contracted lead poisoning as a result of experimenting with TEL, and although debilitated, not die from it. He contracted polio at age 51 and was severely disabled as a result. He rigged a rope and pulley contraption over his bed to help lift him, got tangled up in the ropes one day and died of strangulation.
Well, aren't you just a little ray of sunshine? :goofy:
And smoked it ...
What a way to go. :goofy:
I'm hoping to go when I'm about 95. Shot by a much younger jealous husband. :beer:
And I want to go in my sleep like my grandfather....
not screaming and cursing like the other 4 people in the car he was driving. :goofy:
JamieDaughertyMotorcycle oil is not the same as car oil, it is whooped at a fraction of the miles.
Negative... our oil is not "whooped" at a faction of those miles... what decides
oil life is the additive package which 10% by volume of the total oil and
according to Honda's engineers a typical additive package last 8K miles... if you
are worried about your oil being so called "whooped" send a sample to a lab for
analysis because only they will tell you if your fears are shaky ground or not...
SwitchbladeTetraethyl lead was extensively used as an additive to gasoline wherein it served as an effective ntiknock agent and prevented exhaust valve
True... the *primary* reason for Midgley discovering Tet lead was anti knock... in addition it arrest seat wear...
JamieDaughertyMohawkFresh oil every 2500 miles
Whenever I see this it makes me shudder. The oil should be changed every 1000 miles, maybe 1500 max. Motorcycle oil is not the same as car oil, it is whooped at a fraction of the miles.
Tests indicate, there is no difference between motorcycle and car oils. Deteroriation of viscosity is highest during the first 800 miles of use.
http://www.nightrider.com/biketech/oiltest1.htm
Testresults at the end of the article
No, please, no, not another oil thread.
You done it now !!!!!
Oil is good in lubricating discussions :laughing6-hehe:
Edited December 5, 2013 by VFRBertIf this is going to ignite yet another "Oil Thread" please for the sake of the sanity of all concerned start a new thread!
Oil discussions are endless, so i won't participate in it. The only things about oil i believe are results from research.
Here it comes ......
Oil?
Baby oil and coeds??
Pictures???
;-)
He's waiting for the oil fejitists. :ph34r:
Edited December 5, 2013 by VFRBertToldja ....
VFRD is famous for its "Unbelievable Amount of Technical Knowledge"... we earned
that title by having one good technical discussion after another that challenge
our notions of consumables like tires gas and oil... so let us embrace and add to
the knowledge base or just skip over the topic in silence out of respect for
others...
I agree with BLS, but please let it be silence, every forum I have ever been a member of that debated oils has ended up in a "flaming" war. Unfortunately there are far too many oil experts out there, and they can never agree with each other.
:offtopic:
You will be pleasantly surprised to find this bunch to be more grown up than that. We frequently have disagreement without discord...
Sent from my DROID RAZR HD using Tapatalk 2
"You will be pleasantly surprised to find this bunch to be more grown up than that. We frequently have disagreement without discord..."
I hope you are correct. Still off topic. So that it is not hijacking YoshiHNS' thread, a new thread is needed for an oil debate.
ajcmbrown....a new thread is needed for an oil debate.
No. I'm pretty sure we don't need a new thread for an oil debate. :wacko:
:goofy:
I'm going to order parts this weekend for a rebuild. Still have to take care of the spare valves head I have first.
An oil debate would be useless, since there is a big difference in brands and oil typ's between the US and Europe. I listen to the real experts, there is one tuning specialist in the Netherlands, who has tuned engines to the extreme. He approves only a few brands of oil, because with other brands and types he seas to much wear and tear.
YoshiHNSajcmbrown....a new thread is needed for an oil debate.
No. I'm pretty sure we don't need a new thread for an oil debate. :wacko:
:goofy:
I'm going to order parts this weekend for a rebuild. Still have to take care of the spare valves head I have first.
succes with the rebuild
YoshiHNSI'm going to order parts this weekend
Lets argue USPS Vs. UPS, shall we?
Sorry, I should have explained myself better. I didn't mean that we need another oil debate (God help us), but if it is going to be debated anyway, then it should be a separate thread rather than hijack this thread.
The original topic is of interest to me, not an oil debate.
Edited December 6, 2013 by ajcmbrownWe are indeed away from the original subject. But there are several thing wich influenze wear and tear of an engine, one is oil. The only thing i say about oil is use a good brand and change it at regular times. (mileage or once a year)
I mentioned one other thing, without any reaction, but i think of interest. All damaged cilinders are burnt clean. So ik think, that a lean mixture may be one of the causes. Lean mixture means high temperature's, stressing parts like valves much more than under normal conditions.
Leaking insulators may cause a lean mixture, but leaking valves may cause that to. So controlling valve clearance and doing a compression test may be usefull. And when rebuilding i would ,measure the valve springs, they are 30 years old and may have weakened to much. A valve closing to late cannot dissipate its heat to the cilinder head. Or may even hit the piston.
Absolutely VFRbert, I agree that nothing can replace regular maintenance, being aware of 30 year old weak valve springs, excessive heat from a lean condition like split manifold rubbers, over revving and the many other reasons for a valve failing.
Why are VF500's more prone to this condition than other bikes?
The first thing i think about are the valve springs, they were relatively strong, because Honda switched with the vf series to a higher valve lift and used stronger springs, to close them in time. But stronger springs means more stress to the valve and valve stem. In time and in combination with other factors, like overrevving and overheating this could mean, the valve stem material is fatigued and the damm thing breaks. I had once a broken valvestem in a volkswagen diesel. Never seen such a mess. :wacko:
In addittion tho the stronger valve springs you have the dual cam follower, wich causes more stress to the parts also. Because of the fact, it has to open 2 valves, it has extra pressure from the two valve springs, causing extra wear and the risk of developing sloping wear, when pressure from both valves is different. All those things might give extra stress to parts.
Edited December 6, 2013 by VFRBertThat makes perfect sense VFRbert, Honda occasionally do some strange things that cause issues, chocolate camshafts on VF750's, XR350's with insufficient oil capacity, screen door cam chain tensioners on VF's CB1000's, XL's with points on the end of a camshaft that was prone to float up and down with a bit of wear, etc.
Many years ago while riding my three year old1974 XL350 as fast as it would go along the highway, a rocker snapped and blew a hole in the cam cover, it was not uncommon and the fix was to use the 1976 XL350 rockers since they were much stronger.
Luckily it's not too often but this could be another example.
I have always thought that a VF500 would be a nice engine, but it seems that dropped valves are quite common.
Tony
The VF series nearly costst Honda its reputation as a good engine builder. So they redesigned the whole stuff and astonished the world with the rc24, made the engine even better in the rc36 and put the camchain with its flimsy tensioner back in the 800 vtec. At the same moment accountants and controllers take over a company, they start to cut on costs and end up with inferior products, ending up with less sales. Quality will get worse for a period i think and then they are forced to make better products again, or shut down buissiness. At this very moment i think company's like Kawasaki which alway's made products, with some rough edges on it, produces some very good motorcycles. I hope Honda learns from its faults and start to make perfect products again.
Yes, I remember that accountants almost sent KTM down the gurgler in the early nineties, poor quality, bikes that broke often and were not competitive.
Once the owners took charge again, they started making great quality motorcycles that won world championships and by some miracle, started selling motorcycles in big numbers, look where they are now.
Tony
Everything improves ....
It is always a bummer to see a VF500F engine heading to the recycling bin. These are great engines (and bikes) but they do take some looking after (even when new & especially now after 25+ years with who knows what servicing).
Lots of good info above. If I could add, keep in mind the 500 owner's mantra: a proper warm-up (take the time to get the engine hot & not simply warm before riding), keep the revs in check (I agree this is very hard to do), use a high quality motor oil and diligently maintain the proper valve lash setting - use two feeler gauges here (while checking the lash take the time to also inspect the valve train - look for wear on the followers and cam lobes). This mantra will help to insure the longevity of these amazing engines.
For the valve springs - KPMI offered a VTR250 kit (now discontinued) which should be a match for the '84/'85 (the '86 being a different spec) VF500F. Last I checked with them (spoke with Warren Fong an engineer there a couple years back) they requested sending them a spare head so they could double check the specs. I didn't dive into this at the time as I have a low mileage 500 and a set of spare heads but if this engine is heading to the bin --- perhaps the good head is a candidate to send to them?
Having a source for new valve springs to match OEM would be a great find!
Good luck! Hope you are able to get your 500 back up and running.
InvisibleCities...
Having a source for new valve springs to match OEM would be a great find!
....
timmythecop
If I was to do a full rebuild on an engine, I would start with a VTR250 engine first, since it's half the parts. I would get all new valves, guides, springs, retainers, keepers from KPMI. Then I would start the foolishness and fit Ninja 250 sleeves in the VTR jugs. Then get standard size Ninja 250 pistons from Wiseco. If this all works, then maybe someone else more foolish than me would try it on their VF500 engine.
^ Sounds like fun! Please keep us posted!
InvisibleCities^ Sounds like fun! Please keep us posted!
That's just the thought. Chances of doing it right now are slim
^ Kickstarter campaign? ;-)
InvisibleCities^ Kickstarter campaign? ;-)
It's all about time. First priority is finishing the Magna VF. It already has someone willing to buy it, and I didn't succeed in selling it without an engine, so that has to go. Then start on a full rebuild of the Tomos as a early Bday gift for my sister. Then we now have TWO 4th gen project bikes (not my doing) that have to get fixed and sold ASAP (at least they both run). Have to finish the final bits on the F2 track bike before track days open up. Then I can start on the fun stuff.
YoshiHNSInvisibleCities...
Having a source for new valve springs to match OEM would be a great find!
....
timmythecop
Did a bit more research on the above. Ed Stewart from CV Products (Xceldyne) confirmed that they unfortunately do not offer valve kits (valve springs) for the VF500F. I think this is a snafu on the JCW site.
I think the best bets are either KPMI (bringing back their discontinued VTR kit) or R/D valves. I confirmed with both (now a couple years back) that they would require a spare head in good condition to check the specs - but both felt they could offer kits for the mighty 500.
IC. I came across a thread on VFRW where you said you attached an arcticle showing how Honda said that the VF500 engines were made to maximum capacity (could not be bored out any larger). Do you still have that article? That would make sense if the VF500 was based on the 400cc V4 engine.
^ Sure, of course, will work on scanning and posting the complete article, here is the page you mention:
[image: cycle0784pg27vf500f.jpg]
There you go ....
InvisibleCitiesFor the valve springs - KPMI offered a VTR250 kit (now discontinued) which should be a match for the '84/'85 (the '86 being a different spec) VF500F. Last I checked with them (spoke with Warren Fong an engineer there a couple years back) they requested sending them a spare head so they could double check the specs. I didn't dive into this at the time as I have a low mileage 500 and a set of spare heads but if this engine is heading to the bin --- perhaps the good head is a candidate to send to them?
I could send them my 86 head with one side smashed and the other okay. But is there enough demand for them to bother? $400 to update a (nearly) 30 year old engine? New springs would be great for a preventative measure, but if you have a broken valve, you might have a seat damaged beyond repair, and then more costs pile up.
^ Sending a spare head is definitely a postive thing but I have a hunch this will be up to the individual owner - more a restoration/challenge thing than a group effort. On a side note, the '86 engine has its own unique design so I think there would be more of a market for the '84/'85 which have the same valve spring part numbers and are a match to the later VTR250. The '86 is of course a great engine (some say an improvement over the '84/'85) but there are simply not very many '86s out there as they had a limited production run to start with.
So with what little time I've had, I've managed to take out some of the valves and all the springs from the smashed 86 head. All the springs are well within spec. The two good intake valves I managed to take out were on the low limit for the valve stem OD. The two good exhaust valves that won't come out feel pretty sloppy in the guides. So unless someone can come up with a spec on the spring rate, I can't see the springs being the culprit. I can compress the springs (not fully) somewhat easily with just my hands though.
PS: I've uploaded the 84-85 VF500C service manual to the site. The engine should be the same as the F version.
The elastic modulus of steel is, as far as we are concerned, a constant, so if the springs are in spec on their length then they are OK.
Hmmm probably never know...
How about metal fatigue ?
heh, heh,....he said "modulus".
I think part of the reason I'm pushing on with this is because I like the V4 500. And I technically already had the engine running (just not on all 4 cylinders).
The rest is so one day, if I ever run into Tom again, and I hope I don't, I can shove it into his face that I managed to fix this bike that he scammed on me.
Are you worried about hot spots leading to pre-ignition on the rough edges or are you going to clean them up?
That is cleaned up...mostly. I'm going to leave it as it is. I would be more worried about removing all that material and affecting the flow even more than it is.
My OCD would force me to spend intimate time with a dremel, fine flapper wheel and a beverage with that, good times! Hard to work so close to the valve seat though, would have to be carefull. Speaking of valve seat, you've come this far is there a reason for not doing a quick 3 angle vavle job? (Missed the first 12 pages)
Because I didn't feel like spending the $500+ on the tools to cut the seats :wink:
The guy actually cut the one side of the head that had the damage. Not sure why he didn't just go ahead and do the other side though. But he didn't really charge me much for everything he did.
When you only get about an hour or two a month to yourself, you are forced to put the OCD aside and just get it done well, but not perfect.
Actually made some progress. Installed the new Viton valve stem seals. Very easy and only took a couple of minutes. I had the Motion Pro seal installer, and I'd say it was worth the few bucks.
Now for the retainers. I'm struggling to get the retainers back in without getting one of these tools that I've seen other people use. If anyone has tips, I'd appreciate them. Bit by bit it'll get finished.
Just stumbled on this. And as another vf500f owner (see last month's MOTORCYCLIST magazine), I really appreciate you staying with the rebuild and forging a trail for the rest of us with the same bike. Look forward to seeing it back on the road.
Another update. I know it's unusual to have such a short time between updates, but I'm not gonna complain.
Pic of the new viton valve seals.
[image: DSCF1354.jpg]
So it took a while to learn the trick to getting them in. Once set, it was simply a matter of making sure everything went exactly as needed. Here's a quick pic-guide of what worked for me.
Step 1: Load the springs, valve, retainer.
[image: DSCF1356.jpg]
Step 2: Load 1 keeper. Rotate the retainer or use a screwdriver until the retainer is on the more difficult side to access.
[image: DSCF1359.jpg]
Step 3: Compress the valve spring down part way. It worked MUCH better using the lever action on the valve compressor tool. This way, the retainer stayed where I wanted it, and didn't rotate around to where I wanted to put the second retainer. With it partway compressed, place the second retainer in, making sure it is in the correct location (aka not on top of the other retainer).
[image: DSCF1362.jpg]
Step 4. Compress the spring further while pressing down on the second retainer. I screwed the clamp down slowly, while using either my finger or screwdriver to press the second retainer down. It might take a couple of tries compressing and uncompressing the spring. If the first retainer fell too far, the second one would be very difficult to get in, and it would be easier to just take the second one out and start again. After compressing the spring a little bit more and a little pressure on the retainer, the second retainer will fall in place.
[image: DSCF1363.jpg]
Step 5: Slowly unscrew the valve spring compressor, making sure the retainers remain even with each other and engage the valve.
[image: DSCF1364.jpg]
And you are done. When I was first learning the trick, it took 10-15 minutes at least to do the first one. Once I had it figured out, it only took 2-3 minutes for the rest.
And there was some discussion about valve springs wearing. Well, I went through and measured the spring lengths between my spare head and the original. I kept the longer springs. There was a very clear difference in spring heights between a 'worn' spring and a decent one.
[image: DSCF1365.jpg]
[image: DSCF1366.jpg]
Next is to get the head back on the engine.
Yay
Good job and in auto mechanic's class back in 70's they trained to whack it with a rubber hammer, just make sure the keepers were seated .
SwitchbladeGood job and in auto mechanic's class back in 70's they trained to whack it with a rubber hammer, just make sure the keepers were seated .
I was thinking of this as well, but thought it would be best while wearing safety glasses, and I don't have any at home. Just in case.
Thanks for taking the photos of the springs.
Seeing those springs makes me peed off at Honda for under engineering the VF500 valve train. I suppose at the time they wanted a high engine RPM so they could quote max power output to make the VF sound competitive against the likes of the RD350LC. Unfortunately the consequence was the blown engines we see in this thread.
![[image: 200px-Tetraethyllead-Skeletal-SVG.svg.pn]](http://en.wikipedia.org/wiki/File:Tetraethyllead-Skeletal-SVG.svg){kind=link}
![[image: 180px-Tetraethyllead-3D-balls.png]](http://en.wikipedia.org/wiki/File:Tetraethyllead-3D-balls.png){kind=link}
![[image: 40px-Hazard_TT.svg.png]](http://en.wikipedia.org/wiki/File:Hazard_TT.svg){kind=link}
![[image: 40px-Hazard_N.svg.png]](http://en.wikipedia.org/wiki/File:Hazard_N.svg){kind=link}
![[image: 75px-NFPA_704.svg.png]](http://en.wikipedia.org/wiki/File:NFPA_704.svg){kind=link}