86 vfr750 cams in 86 vfr700 for more performance

i have an 86 vfr700f2 ca. model ...im wondering if any one has knowledge or has attempted to run 750 cams in the 700 motor?

1.is it possible
2.has it been done
3.could it give performance boost .

bike bandit shows the heads match
the gear drives match
valves,springs etc all match
only difference is the cams

i've read the only differences fr 700 to 750 is cams,pistons,rods,stroke,crank,cases and timing. i dont see how timing differs though...they use the same spark units,so other than different pulser placements maybe? is the timing really different...if it is ,would it be possible to modify something on the 700 to accomodate and maybe even make timing adjustable...like a pulser plate slot ?


if you have solid answers or ideas, plz share.

[image: View Post]sjsartwork, on 02 July 2010 - 03:26 AM, said:

i have an 86 vfr700f2 ca. model ...im wondering if any one has knowledge or has attempted to run 750 cams in the 700 motor?

1.is it possible
2.has it been done
3.could it give performance boost .

bike bandit shows the heads match
the gear drives match
valves,springs etc all match
only difference is the cams

i've read the only differences fr 700 to 750 is cams,pistons,rods,stroke,crank,cases and timing. i dont see how timing differs though...they use the same spark units,so other than different pulser placements maybe? is the timing really different...if it is ,would it be possible to modify something on the 700 to accomodate and maybe even make timing adjustable...like a pulser plate slot ?


if you have solid answers or ideas, plz share.


I do know, that the 86 vfr and the 3rd/4th gen bikes share a bolt pattern for the pulsers. In fact, i put the entire ignition system from my 91 into my 86, and it worked flawlessly. So wether the pulsers are rotated around the starter clutch or not is a mystery, im willing to put large amounts of money on the pulsers being the same part number and most likely in the same place. I bet those cams would slot right in there :)

Adjustable pulsers is probably not going to work, btw.

I am by no means a professional mechanic, but I think it would not be worth the effort. The cams in either motor were specifically designed to work with what was going on in each motor. While niether cam is set up for maximum performance, I do trust the fellows who wear white lab coats and specified each cam. If it is a direct bolt on with no other modification, you will most likely gain maybe 3 horsepower with a deficit somewhere else in the power curve.

I very well may be wrong, but it seems as though you are not only trying to get water out of a rock, but an old rock with question marks.

More often than not, the "white labcoats" get superceded by the bean counters when it comes to performance stuff. Plus, max horsepower isnt high on the priority list for white labcoats.

But then again, grip heaters, sidebags and all kinds of other things werent put there stock, but it doesnt seem to phase people putting thosr on, and the white labcoats never intended those to be there either. Not a personal jab, just food for thought ;-)

[image: View Post]flyguyeddy, on 04 July 2010 - 06:37 PM, said:

More often than not, the "white labcoats" get superceded by the bean counters when it comes to performance stuff. Plus, max horsepower isnt high on the priority list for white labcoats.

But then again, grip heaters, sidebags and all kinds of other things werent put there stock, but it doesnt seem to phase people putting thosr on, and the white labcoats never intended those to be there either. Not a personal jab, just food for thought ;-)


Also, the sv650 guys routinely run an intake cam in place of the exhaust cam. I say get some, measure them up, and see which has more lift.

ya, this was just a thought that spun in my head for a while...im not going to do it because of the cost,unless someone already had done it with great results..

i bet it would work good switching them with ca. emission models like mine though...they had less horse power than out of state models....but my vfr700 runs like a champ anyhow,so im not gonna put forth the money or effort for just a few more horses.

unless of course some chimes in that actually did it with great improvements in performance

cool thought though huh?

i found an explanation of difference in cams fr an out of state 750 to a ca, model 750....difference of 5mm lift on lobes and 10 hp.

heres the link with pics and dyno results
http://www.vfrdiscus...345#entry536345

I say do it.

[image: View Post]flyguyeddy, on 04 July 2010 - 10:27 PM, said:

I say do it.



if i ever find some good used ones for cheap,i probably will.
id do it with the 49 state 750 cams

food for thought, plus its harder for me to get bike work done since im a quadriplegic...you know...low funds and little mobility to do work myself..

before you ask,lol, i'll be riding mine from a sidecar with hand controls..
it should be mounted and ridable in about a month..progress is going good with the new vfr.

p.s. HAPPY 4TH OF JULY EVERYONE
I HEAR FIREWORKS

[image: View Post]flyguyeddy, on 04 July 2010 - 06:37 PM, said:

More often than not, the "white labcoats" get superceded by the bean counters when it comes to performance stuff. Plus, max horsepower isnt high on the priority list for white labcoats.

But then again, grip heaters, sidebags and all kinds of other things werent put there stock, but it doesnt seem to phase people putting thosr on, and the white labcoats never intended those to be there either. Not a personal jab, just food for thought ;-)

if you think there is a possibility of 8 extra hp by dropping the motor, exchanging cams and putting it all back together, be my guest. I f you think that bolting in a different cam will be "better" you are just wrong. Honda gets no points for an inefficient motor. I f there were 10 free horsepower lurking, Honda would have used them. You get all excited because you saw a graph on the internet. 5 more mm of lift means absolutely nothing if the carbs, ignition, and bore and stroke are set up for something else.

[image: View Post]timmythecop, on 05 July 2010 - 12:58 AM, said:

[image: View Post]flyguyeddy, on 04 July 2010 - 06:37 PM, said:

More often than not, the "white labcoats" get superceded by the bean counters when it comes to performance stuff. Plus, max horsepower isnt high on the priority list for white labcoats.

But then again, grip heaters, sidebags and all kinds of other things werent put there stock, but it doesnt seem to phase people putting thosr on, and the white labcoats never intended those to be there either. Not a personal jab, just food for thought ;-)

if you think there is a possibility of 8 extra hp by dropping the motor, exchanging cams and putting it all back together, be my guest. I f you think that bolting in a different cam will be "better" you are just wrong. Honda gets no points for an inefficient motor. I f there were 10 free horsepower lurking, Honda would have used them. You get all excited because you saw a graph on the internet. 5 more mm of lift means absolutely nothing if the carbs, ignition, and bore and stroke are set up for something else.



...like i said before my bike is a ca. model which needed to meet emissions requirments....personally i think theres room for improvement, you dont think so...but lets hope to hear from someone whos actually tried it or at least people with an open mind.

experimentation can lead to ?????who knows ; )

[image: View Post]sjsartwork, on 05 July 2010 - 01:05 AM, said:

[image: View Post]timmythecop, on 05 July 2010 - 12:58 AM, said:

[image: View Post]flyguyeddy, on 04 July 2010 - 06:37 PM, said:

More often than not, the "white labcoats" get superceded by the bean counters when it comes to performance stuff. Plus, max horsepower isnt high on the priority list for white labcoats.

But then again, grip heaters, sidebags and all kinds of other things werent put there stock, but it doesnt seem to phase people putting thosr on, and the white labcoats never intended those to be there either. Not a personal jab, just food for thought ;-)

if you think there is a possibility of 8 extra hp by dropping the motor, exchanging cams and putting it all back together, be my guest. I f you think that bolting in a different cam will be "better" you are just wrong. Honda gets no points for an inefficient motor. I f there were 10 free horsepower lurking, Honda would have used them. You get all excited because you saw a graph on the internet. 5 more mm of lift means absolutely nothing if the carbs, ignition, and bore and stroke are set up for something else.



...like i said before my bike is a ca. model which needed to meet emissions requirments....personally i think theres room for improvement, you dont think so...but lets hope to hear from someone whos actually tried it or at least people with an open mind.

experimentation can lead to ?????who knows ; )




dropping the engine is hardly required for a cam swap. if our engines had a cam chain with no master, then i might be tempted to agree with that. getting to the camshafts on our bikes is very easy, if i were local i would come and help you.

you seem to have taken what i said as a personal jab against you, and that was not at all what i was trying to do. i was just making an illusttration that no motorcycle is optimal from the factory. if that were the case, then aftermarket exhausts would not be sold. saying that a cam swap with more lift and duration wont make more power without supporting mods i can totally agree with. but his bike is a ca model, and you can bet your lucky stars its way detuned from the factory to meet californias emmissions standards.

[image: View Post]timmythecop, on 05 July 2010 - 12:58 AM, said:

[I f there were 10 free horsepower lurking, Honda would have used them.


Sorry, but not necessarily in California, back then. Honda absolutely detuned bikes to meet CA emissions standards. Whether you consider that "inefficient" depends on your perspective. :cool:

To your last point, the whole crux of this is that the OP is indeed assuming/hoping all other things (carbs, etc) are either the same as the 49-state version, or easily modifiable to be so. Given Honda's manufacturing savvy, I don't think this is far-fetched. They probably only ground two cams as a last resort, anyway.

To muddy the waters even more....


Why not just send your stock VFR700 cams out to be reground? Even the VFR750 grind could use some improvement. Shadbolt, Megacycle, WebCams, etc. will all grind whatever you want. Just going stock-stock takes the same amount of effort, so why not go all the way?

i sure wish someone has done this before....i bet it could work well with a few mods like jetting,filter, exhaust changes...dropping emission b.s. and possibly even advanced timing either through physical change or digital mapping.

these motors already have high compression ratio and light drag cam driven gears for high revs...it would be bitchen to have cams,carbs,exhaust,timing, matched for better power..

the 750 cams and 700 cams look physically the same except for lobe height/rise judging from some ebay pics i found

i can sure see why curiosity killed the cat....sometime wondering about such things are addictive...lol

i hope somebody gets inspired to take the ball and run with this one,posting results at a later time...like after dyno runs ; )

p.s, thanks for all the well thought out feedback guys.to those that are quick to say NO NO,it cant be done,or try to make you feel lame for dreaming,i say....i bet you never thought a quadriplegic would be piloting a vfr by himself either....

were theres a will.....theres a way

[image: View Post]JamieDaugherty, on 05 July 2010 - 10:20 AM, said:

To muddy the waters even more....


Why not just send your stock VFR700 cams out to be reground? Even the VFR750 grind could use some improvement. Shadbolt, Megacycle, WebCams, etc. will all grind whatever you want. Just going stock-stock takes the same amount of effort, so why not go all the way?



thats a good point jamie....the main reason is that im no cam guru so i wouldnt even know what to ask for,,,but seeing as the 49st 750 put out such good powr with only 50cc more,i figured the cams must be set for pretty good output...

maybe someone like you or someone with more cam knowledge than myself period, could have great results with a regrind...but can they add metal if need be for as little as it might cost for used 750 cams?

[image: View Post]sjsartwork, on 05 July 2010 - 01:05 AM, said:

...like i said before my bike is a ca. model which needed to meet emissions requirments....personally i think theres room for improvement, you dont think so...but lets hope to hear from someone whos actually tried it or at least people with an open mind.

experimentation can lead to ?????who knows ; )

This is the best idea yet. I am speculating, and maybe somebody has done it with good results, like you say who knows? either way I hope you get good performance out of your motor, and I would love it if I was wrong and you could bolt in an improvement. (me being wrong Vs. a better engine for you is an easy choice :fing02: )

[image: View Post]timmythecop, on 05 July 2010 - 07:41 PM, said:

[image: View Post]sjsartwork, on 05 July 2010 - 01:05 AM, said:

...like i said before my bike is a ca. model which needed to meet emissions requirments....personally i think theres room for improvement, you dont think so...but lets hope to hear from someone whos actually tried it or at least people with an open mind.

experimentation can lead to ?????who knows ; )

This is the best idea yet. I am speculating, and maybe somebody has done it with good results, like you say who knows? either way I hope you get good performance out of your motor, and I would love it if I was wrong and you could bolt in an improvement. (me being wrong Vs. a better engine for you is an easy choice :fing02: )



thanks tim....i gotta say though luckily this old viffer runs and sounds great,soon to be on the road again...
a guy in my position doesnt really need the fastest vfr ...im not willing to sacrifice reliability for power.....but maybe someone else might.

its just cool to ponder the possibilities.....which is usually the start to new horizons....anyhow...cheers to all of you vfr lovers...im becoming one very quickly,especially after hearing my new supertrapps today!!! what a sound...


this thing should be plenty fast enough anyhow...i moved up from riding a gutless 78 hondamatic 400 to the vfr....so YEE HAA

[image: View Post]sjsartwork, on 05 July 2010 - 05:00 PM, said:

thats a good point jamie....the main reason is that im no cam guru so i wouldnt even know what to ask for,,,but seeing as the 49st 750 put out such good powr with only 50cc more,i figured the cams must be set for pretty good output...

maybe someone like you or someone with more cam knowledge than myself period, could have great results with a regrind...but can they add metal if need be for as little as it might cost for used 750 cams?



There is some info around, so I'm sure you could come up with something much better than a stock VFR750 grind. I'm sure that I've got the specs somewhere in my notes.....

[image: View Post]JamieDaugherty, on 07 July 2010 - 11:14 AM, said:

[image: View Post]sjsartwork, on 05 July 2010 - 05:00 PM, said:

thats a good point jamie....the main reason is that im no cam guru so i wouldnt even know what to ask for,,,but seeing as the 49st 750 put out such good powr with only 50cc more,i figured the cams must be set for pretty good output...

maybe someone like you or someone with more cam knowledge than myself period, could have great results with a regrind...but can they add metal if need be for as little as it might cost for used 750 cams?



There is some info around, so I'm sure you could come up with something much better than a stock VFR750 grind. I'm sure that I've got the specs somewhere in my notes.....


im sure your right...i just dont have the funds to play with this idea yet. i dont want to waste your time gathering info when i know i cant afford it, but thanks anyways....

[image: View Post]sjsartwork, on 07 July 2010 - 08:37 PM, said:

im sure your right...i just dont have the funds to play with this idea yet. i dont want to waste your time gathering info when i know i cant afford it, but thanks anyways....



You might be surprised. How much are you planning to spend on new/used VFR750 cams? $200? $250? The last I checked, getting your current cams reground was under $300. Regrinding what you have to a performance profile is a very cost effective method.