A Complete Disaster

Hello all!

I recently bought a 95' VFR750 basket case with the intensions on having a fun daily driver and to knock a bike off of my bucket list of 'bikes to own'. After purchasing it and getting into my garage to give an in depth look over, the thing is in VERY rough shape. The bike is in pieces (hence basket case) with every electrical connection disconnected from it's original place and no service history or proof of actual mileage. The wiring has been hacked up and eaten up by mice it looks like, over the years of sitting, and after pulling the plugs I found oil on them, one heavier than the others, which concerns me. Below are some pics of the bike after it was unloaded from the truck. 

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I got discouraged after the in depth inspection of the condition of the bike, but after looking into several threads by other members, I am confident I may be able to get this one at least running/ road worthy. The title is bonded so not too worried about returning to stock or making anything pristine, so my plans are to make it into a 'street fighter', 'naked' build. 

My first trial with the 'Disaster' was trying to see if it would at least crank with the battery provided after having it sit on the tender over night. That did nothing... but keeping in mind the battery hadn't been used in 4-5 years along with the rest of the bike I wasn't too concerned. I then ripped a battery out of my other bike and tried that, and got nothing. After a night of more thread reading and a further look at the manual I had another set of things to check the next day.

So this morning I checked the main connections to the battery, 30 amp fuse and starter relay.. that's when I found this.. 

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After some short video tutorials on wire/ connector repair, and keeping my VERY small budget in mind, I decided to try and salvage/ repair the existing burnt up connectors the best I could to see if I could at lease get the bike to crank. I made the below repair, using my cheap Radio Shack soldering iron I purchased several years ago, but it gave out on me halfway through the joint. So that's where I'm at, I'll purchase a new soldering iron tomorrow and get to work repairing the rest of the connectors and wires as much as I can. 

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The community surrounding these bikes seems pretty amazing, so I'm looking forward to anyone willing to offer advice and insights and seeing if I can keep another viffer on the road. 

Welcome to VFRD from across the pond  :beer:

My bet is that once you fixed that burned connector you are half way there.  Hook her up to a car battery and see if she'll fire up. Fit a voltmeter to see what the generator and voltage regulator put out.

Once she fired up, I'd chance oil/filter and start going through "the drill" and hydraulics.  Been there, done that...

As long as you did not pay more than a couple C-notes, you can only win! (in terms of fun with a V4, not resale!)

Hi Brandon.

Welcome to the forum and good luck with the 95 VFR750 resto.

The burnt up connector you're holding is the Stator output 3phase wires joining to the R/R. Best to just neatly solder and sleeve this wires together - problem solved!

A battery sat idle for 4-5 years will be shot to pieces.

Your Starter Circuit should look something like this - See Attached.

So to get your Starter to crank over you can simply short out the two main Starter Terminals with a screwdriver or similar MAKE SURE BIKE IS IN NEUTRAL.

OR via the normal wiring method - As you can see, the two starter coil wires are the Yellow/Red being the Positive seeking side and the Green/Red being the Ground seeking side.

So if you're in Neutral you need to have a good Neutral Switch, and good Clutch Diode to satisfy the Green/Red wire. You also need to have a good 30a Main Fuse, a good Ignition Switch, good 10a Sub Fuse, good Starter Switch and good Stop Switch (in RUN mode) to satisfy the Yellow/Red wire. Along with all the associated wiring of the above devices.

Hope this helps.

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Check out Cycle Terminal for replacement connectors and terminals (they're not expensive).  Welcome and good luck!

Ciao,

JZH

Thank you every one for the replies!! @Grum, I took your advise and just directly connected the 3 yellow wires together to simplify the repair. I also went through the 'main' wiring for the stuff that makes the bike run and repaired all the hack jobs/ mice damage I saw. I also found some blue tape and thought it was more 'work' from the PO, but the seem to be OE solutions (see second pic). I'll leave those alone for now. 

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After I was satisfied with the condition of the wiring I had been working on, I moved to the front of the bike to address the ignition switch that the PO had put in place of the keyed ignition because he lost the key to the bike. Cleaned the switch up and checked the fuses up front, had to replace a blown ignition fuse. After that, I again took the advice of @Grum and @Dutchy and hooked the bike up to my cars battery and shorted the starter wires to see if it would even crank... and viola!!! At this point I was feeling VERY good about my self and got most of the connectors hooked up, including a disconnected neutral safety switch. I then tried the bike with the starter switch and it turned over from there as well!! 

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 I then moved on to see if the bike had spark and hooked up all the coil packs and tested each spark plug... all 4 had spark, things were looking good. I threw the dirty plugs in that I did my best to cleanup, and sprayed some carb cleaner in the air stacks, just to see. It almost roared to life but needed a more consistent fuel flow. I grabbed the beat up tank I was given with the bike with some left over gas in it and gravity fed the bike. I tried for about 10 minutes to get the thing to fire up with no luck. I did get it to putter a bit and it sounded healthy (other than the carbs pissing gas everywhere, probably due to open drain screws that I didn't check prior to starting) I called it a day after that. This week I'll take the carbs off and give them a quick inspection/ clean and go from there. 

I'm beyond excited to almost have the bike running a this point and can't wait to see what's going on inside the carbs. I don't intend to keep the current ignition switch in place, nor do I plan on keeping the old rotten plugs or anything else for that matter on the bike if I'm able to get it running reliably. I'm still seeing if the bike is salvageable, mechanically speaking before throwing any new parts at it.  

Will spend tonight researching carb rebuild videos/ threads. Again, thanks everyone!!

Wahey!!!  :beer:

Now you feel embolded, open up the hydraulic reservoirs!  Best done with a JIS screwdriver. Be careful as them tiny bolts are quite soft...

Keep an impact driver at hand.

What a mess! Those Green wires you are holding are Ground wires. That unconnected Blue/Orange at the Ignition Switch is the cooling fan power normally switched to ON via a proper Ignition Switch, it then goes to feed Fuse G Fan Fuse.

Oh man, that's a project! Great to hear that it's already making positive headway - Honda do seem to have made a bike which, at it's core, is almost indestructible by human hands!

See a lot of this kind of thing on eBay, people have had the idea of making a streetfighter after binning the bike, got as far as tearing it all apart, then given up because it's hard to do and left the poor bike to languish for years. It's a real bummer that so many gen 3's especially are going to end their days like this as the aftermarket parts just aren't there for them. In the UK the number of listed legally running bikes from this era is less than half of the number declared "off - road" and even that's only a few hundred

For zero dollars, it looks like you're doing great! There's a youtube guy that might be worth a look. He goes by Superfastmatt. I think he's in California.

https://www.youtube.com/c/SuperfastMatt/featured

I don't know him. Only his videos, which can be helpful. And funny. Here's his self described bio:

As a testament to HONDA's technical prowess in engineering solid bikes....

This VFR800fi stood outside for (iirc) 7 years under a tarp all year round. The fule cap would not open, so used the fule that was in there. the battery was well farked, so hooked up a known to be good one.

3 jabs on the starter button

this VFR750 stood idle (inside a non-heated but dry) shed for 5 years. Battery toast

Once I knew it would run, I started spending money... (battery, oil, tyres etc etc)

If she works out to be solid mechanically, maybe a solution to the wiring mess could be to buy a used harness.  They're around on ebay for reasonable money. 

judging by the melted connector between stator and r/r, i think you will need a NEW stator since it's ruined. not the wires but the stator itself.

Let us know if you get it running, and you decide to continue. From my street fighter bike, I have a start/stop switch from a 3rd gen I can give you - yours if you want it! It may not be the right part number, but it will work, and it's FREE!

Hi all, I definitely plan on getting to the hydraulics soon enough, but they're not on the top of my list just yet. As for the ignition I'll be taking the passenger peg/ bracket assembly with the keyed seat latch to the lock smith tomorrow in hopes they'll be able to make a key for it, and crossing my fingers that it's the same key cut and it'll match my keyed ignition so I can wire that back up properly.

After sitting at work all day today itching to get home and continue wrenching on the bike, I realized the reason I probably hadn't been able to get it started was I kept giving it gas (flooding the carbs) and using the who-knows-how-old gas that was left in the tank. After I got off from the ole' 9-5, I picked up a new bottle of carb cleaner and filled my portable gas tank with new, fresh gas. I drained the old gas out of the tank, filled it with new gas, sprayed the intake stacks with a squirt each of carb cleaner... and after a few pops and bangs, got the bike to idle for a full 10 seconds!!! Even enough for a quick rev!!! I was beyond excited, and the bike sounded healthy, aside from the gummy carbs. 

I decided that hearing it run for that split second was justification enough to start doing the basics of getting it running and idling reliably. I then took off the carbs and gave them a quick once over. pretty much every jet is clogged shut and found a broken off choke-plunger, but they look good on the inside and may only need a good solvent soak and jet cleaning/ bowl gasket replacements.

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My hands were too dirty to grab my laptop to view the amazing write up by the lovely gentleman that made this guide http://v4dreams.com/maintenance.html and continue the carb teardown, and I was too lazy to wash my hands, so I tore down the front end to give myself more room to continue repairing the harness up front and start mounting the radiator/ oil cooler. 

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Honda does know how to make a practically indestructible bike!! The moped you may see in the back ground of my pics is an 18' Grom with 4k HARD miles. I've redlined the thing in every gear since I purchase it new and have tried to blow it up so I have an excuse to build the motor, but to no avail. It's the most fun bike I've ever owned and will probably never part with it! Better to go fast on a slow bike, than slow on a fast bike!! 

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Tomorrow is beers with my buddies, so probably won't make any more progress until the middle of the week.

Hey, good job on getting wiring repaired! That's some difficult stuff!

Caveat about carbs, running is not indicator of condition. You'll need more extensive restoration steps:

- replace all float-valves

- replace fuel-rail O-rings

- replace float-bowl seals

- inspect, R&R slide diaphragms

Basically any soft rubber part should be restored to OEM condition. Leaking you encountred is sure sign that one or more of above is not sealing properly.

brandon750, 4/19/2021 at 2:24 AM

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Ah, the ol' Honda 2" wide blue 'leccy tape... Yes, it can be found (along with the brass crimp wire splices) if you search long enough.  

One thing that's surprisingly hard to find in the US (as opposed to the UK) is thin-wall cable in a multitude of colors, if for example you need to re-build a wiring harness and want to use OEM wire colors.  The thinner sizes (0.5mm2 and 1.0mm2) come in up to 100 solid and striped combinations.  (The cheapest source I've found in the UK for 1m lengths is ALM Solutions, btw.)  

For absolutely authentic OEM cable (most of what I've seen is locally manufactured and not exactly the same as OEM) you can visit www.hi-1000ec.com, which is a Japanese site selling mainly OEM electrical connectors, but they also stock Sumitomo automotive cable which looks just like OEM.  But that's a bit extreme--even for me!

Ciao,

JZH

soaking carbs is best avoided as the throttle shafts can seize up later during storage due to solvent/water infiltration. a toothbrush and gasoline will clean well without that risk.

(yeah, i know this is heresy.)

Here's another source of connectors, terminals and wiring.

https://www.corsa-technic.com/

Personally, I don't like using OEM-spec anything as it's always designed to certain price-point. I prefer to upgrade specs to military/aerospace standards. That means sealed weather-proof connectors and terminals. Along with silicone-insulated, pre-tinned wiring. Then tie/crimp+solder+heatshrink assembly process. There's never enough time to do it right the first time, but there's always time to do it again. Often on side of road in total-darkness and rain!

19 minutes ago, DannoXYZ

 There's never enough time to do it right the first time, but there's always time to do it again. Often on side of road in total-darkness and rain!

Ain't it the truth . . . seen it too many times. 

2 hours ago, DannoXYZ

, but there's always time to do it again. Often on side of road in total-darkness and rain!

While adventures suck at the time, they make for great stories over a couple of beers...  :beer:

There's never enough time to do it right the first time, but there's always time to do it again. Often on side of road in total-darkness and rain!

Hahahaha, been there, done that!

Took the top triple to a lock smith this morning to see if I could get keys made (those ignition bolts were NOT coming out) and they were able to whip up a pair in about 5 minutes!! No questions asked lol! I'll order some electrical connectors from the recommended sites here soon and keep plugging away (ha-ha) at the wiring harness and get the keyed ignition hooked back up and tested. 

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I also was able to finish tearing down the carbs and got a list of new parts that need to be ordered, hoping to find a complete rebuild kit for a decent price. I'm going to look at tutorials and talk myself into replacing the fuel o-rings while I have everything apart. Hopefully I'll get some parts in by this weekend and make some good progress over the coming week or two.

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For rubber carb parts, try LiteTek in (of all places) Thailand.

There's nothing wrong with OEM cable, but OEM connectors on VFRs are notorious for suffering from corrosion.  I do not replace unsealed OEM connectors with sealed ones (the cost and effort would not be worth it), but I do make sure that the terminals are covered in dielectric grease to seal out moisture.  However, if I'm installing a new circuit I generally use Delphi Metri-Pack sealed connectors, which are good quality and available everywhere.

Ciao,

JZH

Just found it in my box of used parts. Let me know Brandon, it's yours if you want it. Just PM me your address...

20 minutes ago, RC1237V

Just found it in my box of used parts. Let me know Brandon, it's yours if you want it. Just PM me your address...

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@RC1237V Thank you so much for the offer!! I think mine is good, but will need further inspection and testing. I'll let you know!

Had to work late tonight so no progress to report.

If you get tired of working on carbs, I highly recommend Gordon @ https://customcarbservices.com/

He's got VFR as well and does amazing refurb and restoration work. I've sent him at least 10 sets of carbs in recent years and they come back in perfect 100% OEM factory-clean condition. Bikes have never run better. Uses all OEM rubber parts.

Although LiteTek kits are awesome as they use latest better-than-OEM flouro-elastomer seals. Haven't made comparison for carb-seals, but using them for valve-guide seals has really been great on my engine builds.

10 minutes ago, DannoXYZ

If you get tired of working on carbs, I highly recommend Gordon @ https://customcarbservices.com/

He's got VFR as well and does amazing refurb and restoration work. I've sent him at least 10 sets of carbs in recent years and they come back in perfect 100% OEM factory-clean condition. Bikes have never run better. Uses all OEM rubber parts. Although LiteTek kits are awesome as they use latest better-than-OEM flouro-elastomer seals. Haven't made comparison for carb-seals, but using them for valve-guide seals has really been great on my engine builds.

Thank you DannoXYZ, just bookmarked the carbservices website. May need it in the future.

3 hours ago, Wald

Thank you DannoXYZ, just bookmarked the carbservices website. May need it in the future.

You're most welcome!

Spray carb "cleaners" no longer work due to removal of chlorinated compounds. He really knows carbs and has all equipment to do proper restoration.  Has ultrasonic cleaner with correct chemicals for proper soak. Also micro soda-blaster. No DIY home-mechanic can do proper carb-refurb without them. He's in NY and has speedy turnaround.  Usually around 1-week and that includes shipping-time to CA!!  :fing02:

Spent the evening cleaning carbs... The bodies are (mostly) as clean as I want them and I got through one set of jets and a bowl, the bowls require EXTRA attention. I also ordered all the carb parts I need, including fuel rail o-rings and others from Joe at V4 Dreams and after a shipping mishap on my part, they're on their way! 

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Also took the rear wheel off to start looking over all the rear end components. 

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before you button up the carbs it's good to spray a mist of WD40 all over everything to prevent dry corrosion oxidation (alox). how many miles on the bike ?? if it's anything over 35k miles or if they haven't been replaced after the crash, you'll need new steering head bearings.

10 hours ago, squirrelman

before you button up the carbs it's good to spray a mist of WD40 all over everything to prevent dry corrosion oxidation (alox). how many miles on the bike ?? if it's anything over 35k miles or if they haven't been replaced after the crash, you'll need new steering head bearings.

I'll be sure to give them a spritz of WD40. And as for mileage.... The PO claimed the bike has 100k miles, and I just don't believe that. The bike didn't come with a cluster and I think a bike that is capable of hitting 100k would have had to been maintained MUCH better than this poor bike has, if maintained at all. I do plan on replacing the steering head bearings, and my parts list grows larger and larger everytime I take something else off the bike.

This is a good source of gaskets, O rings, etc at bargain prices .. https://www.ebay.co.uk/str/usaview?_trksid=p2047675.l2563

I got a complete 4 carb set of jets, washers, etc for less than $20 delivered 

Good luck .... my 89 RC24 was in a similar state, squirrelman was a great help setting the carbs up

Progress has been slow going this week waiting on carb parts and trying not to bite off too much at once. Carb parts arrived today from Joe at V4Dreams and I got to work disassembling the carbs and replacing the fuel rail o-rings, with the intent on getting the carbs all buttoned up today and leak test them overnight... but ran into a tiny issue. The large 'air vent' tube o-rings fell apart when taking apart the carbs and will need to be replaced. 

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I'll try to find a place to source these o-rings locally, along with the 2 small coolant hoses that live underneath the carbs tomorrow after work. I'll also need to take the metal coolant fitting and thermostat hosing off for a good cleaning before re-assembly as there is a lot of build up inside the entry way's of the tubes.

Expect to find the O rings on the pipe and thermostat to fall apart, there’s one inside the rear head for the pipe

Not changing the float level valves?

Carbs are all cleaned, rebuilt and put back together. Taking them apart was pretty daunting for me to replace the fuel lines and o-rings but I got through it with the help of Joe's tutorials at V4 Dreams! 

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I leak tested them and no gas was found weeping out anywhere that it shouldn't. @Thumbs The PO stated that the carbs had been rebuilt throughout the years he had tried to get it running again and the float valves seem to have shown that. They were in good condition so I gave them a good scrub (though they didn't really need it) and called it good, time will tell if this was a good decision on my part.. lol. You were correct about the o-rings in the coolant piping and thermostat housing falling apart, i'll be ordering those, along with some new steering stem bearing to begin reassembly of the cooling system/ front end and (hopefully) get the bike running reliably here soon. 

The reason I asked was this guy is doing complete 4 carb kits including float valve for $20 delivered 

https://www.ebay.co.uk/itm/174527528066

Been plucking away at cleaning up the bike, refurbing parts and figuring out the wiring mess. I about gave up on trying to repair the harness but the only replacements available right now are outside of the US and I don't want to pay $40+ just for shipping so will be doing an in-depth look at the wiring diagram and ordering OE-style connectors and pins to replace and repair everything on the harness I have for now. 

O-rings for the coolant piping under the carbs came in along with new steering head bearings. Put the front end back together to hold cables and such while I continue on my journey to get the thing running correctly. Makes me happy seeing it start to come back together!

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I put the carbs back on and tightened all the clamps and tried firing her up... would crank and try but no idle was achieved. I could get the bike to fire right up with a couple sprits of carb cleaner but not with a flow of gas. Seems like the bike isn't getting enough fuel. Anything I should try to troubleshoot this? I'm gravity-feeding the carbs as I have no fuel pump yet and bowls have gas in them. 

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^^  they never run right unless the full airbox and filter are in place.  is your choke hooked up and working ?

be sure that both forks are set to the same height at the top clamp.

22 hours ago, brandon750

I put the carbs back on and tightened all the clamps and tried firing her up... would crank and try but no idle was achieved. I could get the bike to fire right up with a couple sprits of carb cleaner but not with a flow of gas. Seems like the bike isn't getting enough fuel. Anything I should try to troubleshoot this? I'm gravity-feeding the carbs as I have no fuel pump yet and bowls have gas in them. 

You're not 1st one to ever have this issue. If bowls are filling up to float level, then petrol is not making it from there into engine. Joe's procedure might work for carb that's been sitting for 1-2-years, but certainly not 10-years. Your carbs need full disassembly and refurb...

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Different carb, but all Keihin CV carbs are similar. Remove jets and scrub hidden secret fuel-circuits clean from end-to-end. I like using 50/50 mix of acetone/ATF, much better than "carb cleaner" sprays that no longer work due to removal of chlorinated compounds. Or undiluted PEA-based fuel-system cleaner also works. Amazon - Carb Cleaning Brushes.

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Poke out all bleed holes in jets and emulsion tubes with matching gauge copper wire. It'll push out little dried-petrol plugs like grains of sand. Be extremely careful not to gouge holes and change their diameter. Heck, there was recent case where choke-jets had to be drilled with micro bit because dried-petrol was so tough!

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Then soak everything (except diaphrams) in ultrasonic cleaner for 6-12 hrs. Rinse, dry, then micro soda-blast to clear out remaining chunks chipped off from scrubbing and poking.

Reassemble with all new rubbers: float-valves, fuel-rail O-rings, float-bowl seals, and slide diaphragms if needed.

There's tonnes of extremely skilled mechanics who can rebuild engines with their teeth and hands tied behind their backs, who've had to pull their carbs 4-5x to do ever deeper cleaning and restoration until it was factory-fresh clean. Then bike runs just like it left showroom floor. I recommend you do that 1st time around. Well, second time now...

I actually do this on my race-bike carbs every winter during off-season to maintain maximum performance.

^^^^^^^  those carbs above are nothing like VF or VFR carbs.  🙄🙄🙄

VF/VFR carbs still have petrol-passages between jets and carb-venturi.

Jets need to be removed and those circuits needs to be completely scrubbed clean.

Bleed holes in carb-venturi are also extremely easy to block.

That's where majority of blockages are in cases like these.

soaking carbs is no cure all, usually unnecessary and may lead to frozen-solid throttle shafts during storage.

10 hours ago, squirrelman

soaking carbs is no cure all, usually unnecessary and may lead to frozen-solid throttle shafts during storage.

There’s felt washers inside the carb bodies on the throttle spindle, if they’re not kept lubricated the spindles can rust and lock up exactly as described 

My #1 carb had been subjected to frequent squirts of petrol by the PO then he left if for a while and the carb seized up solid

Yup,  a little spritz of WD-40 or silicone lube should be done as regular maintenance.

Regardless of cleaning nuances, bottom line is OP's carbs have not been sufficiently disassembled and thoroughly cleaned to restore back to factory-fresh clean condition. Bike will run like brand-new off showroom floor when carbs are factory-fresh clean. Fact that it doesn't, means carbs aren't factory-fresh clean.

to lube throttle shafts set the carbs on their side and place some oil where they merge into the carb body and let them sit for a day, then do the other side and let that sit for a few hours, allowing oil to feed down to felt washers.  especially important if carbs were soaked.