engine conversion

I have an 86 vf500f and I have heard that the vf500f and the vf750 share the same exhaust system. someone told me that the 750 was just a bored and stroked 500. my question is to anyone who might know, will the 750 engine fit into a 500 frame, and if so, will it be a bolt in and go. or is this just a pipe dream of getting a little more power in my bike without ruining the great handling characteristics it has. by the way, a works performance rear shock does wonders for the bike, everyone was telling me the front end was the problem. after the rear shock instal, all my complaints went away, but I do have a set of racetech gold valves and progressive springs to instal later along with all the goodies that should be done.

 

No, a 750 motor will not fit in a 500 frame.

 

No, it will not fit in the 500 frame.

Now a VF1000 engine will fit in the VF750 frame , there is pics of such on the web..

 

Dont the VF1000 and VF750 use the same chassis? or very simular frames anyway. I know that the VF1000 engine has the same bottom end as the 750 just with larger cyls on top thus why the two would work in the same frame.

 

Is that correct?!! A 1000 motor will fit in a 750 frame? Any mods have to be made or is it just a direct swap? I want more power and that would be the easiest way to go. Nailer do you know where on the web? I'd like to see that and or get in touch with the person that did it.

 

Tim Cameron of VRex fame, transplanted a VF1000R motor into his bike. But with the VF1000R, you have to drop the engine slightly to get the rear valve cover of. You don't have to do this with the VF1000F motor.

The Gimp
Build a Gimp!

 

I don't know enough about these bikes to know what is the difference between an f and an r motor. they must be different in dimensions but being of the same displacement. or am I wrong as usual?

 

I believe the "R" has gear driven cams, while the "F" has cam chains and tensioners.

 

Sure, this is really not that hard. Keep in mind that the 1000F engine needs the exhaust that goes with it, the 700/750 exhaust will not bolt to the 1000 heads. You'll also need to use the VF700/750 airbox because the 1000 part does not fit under the 700/750 tank. Otherwise it's a pretty straightforward swap.

 

That would make a nice sleeper bike. Looks like a 750 but with the 116hp of the 1000 should make it run pretty good. You would have to get a bigger rear tire for the power. May be larger brakes to stop it. I wonder if the radiators can handle the extra heat?

 

So basically you want a VF1000F!

 

What about ca110's question regarding "F" v "R"?

My information is that there were two designs of the VF 1000 engines based on the kind of output drive used. The VF1000 cc motors of both types were produced between 84 and 86. The VF 1000 R motor was made in 85 and 86 and it had the gear driven cam changes. But the denotation of "F" or "R" pertains to whether the big heavy VF 1000's were chain or shaft driven, output drives, not whether they had gear driven cams or not. I do not know the exact story of when the VF1000F was fully converted to gear driven cam. There had to be some 84-85 1000cc VF motors that had chain driven cams and chain output drives too. This history is not readily available. I do not know the difference between a VFR 700/750 F and a VFR 700/750 F2. I have read that the VFR 700/750 F2 was the motor that got the gear cam drive before the VFR 700/750 F. But I'm going to find out next week when I pull the cam covers and retorque my F's heads prior to valve adjustment.

 

The answer about "F" re "R".

The VF1000F was the first VF1000 cc machine that probably led to the recall of the early VF chain drive cam motors. The VF1000 F was only produced for one year, 1984. The "fix" was the gear type cam drive that appeared on 1985 VF1000 R models. These were sold with shaft final drives as well as the redesigned gear driven cams. The VF 1000 models were capable of 150+ mph top speed. They were discontinued after 86. The 1000's are described by the reference I am using as "memorable but not highly desirable machines" due to weight and complexity.

 

re f or r

my understanding was that the only chain drive cam was the 500, everything else was a gear drive. I just bought an 83 vf 750 interceptor off of ebay last week and am going to pick it up sunday, I own an 86 vf500 interceptor. I expect the 83 to be a gear drive cam, that should be the litmus test as the 83 is the first year of the vf's to see if all the larger displacement ones were gear drive . from what you said, the vf 1000's came shaft drive if it was an "r", does that mean an interceptor as well? by the way, pretty macabre statement.

 

Nope the 83 thru 85 750 Interceptors have chain driven cams. The 86 was the first year for cam gears in the 750's. I have a noisy one in my 83 now. I think it's the tensioner not sure till I take it a part. You can check motor parts at cheapcycleparts.com. Go to OEM parts look up the year you want and they have all the parts fiche with numbers. I thought the VF1000F were the same. Haven't checked those though. There are about 3 or 4 revisions on the tensioners for those 750's.

JamieD Yes would like to have a VF1000, but would rather have the hp in my smaller package 750. I love sleepers.

 

Actually, that is not incorrect. Both the F and R engines had chain final drive outputs. The S and C models (1100cc by the way) were shaft drive.

Here is a brief overview of tha cam drive:

1984 VF1000F: chain
post-84 VF1000F: some had gear drive but never sold in the US, so I don't know the exact years
1984-86 VF1000R: gear
all others: chain.

 

"F" v "R" controversary.

I was reading and quoting from a Honda motorcycle collectors handbook published in the USA around 2001. I can't remember the author but it was one of a series of paperbacks on collecting motorcycles. On this authors list of desirable collectable Honda models of motorcycles was the VF 700/750 and the VF 500 and he mentioned the VF 1000 but he was not very enthusiastic about the VF 1000 because it was supposed to be too heavy to have the drivability characteristics of the smaller lighter VF machines. He was very definite about the history behind the VF1000F and the VF 1000R. Although he was very high on the 500 and the 750 VF's as beautifully balanced and fast bikes he implied that the VF1000F which he claimed had been produced in the first year of production of either the 750 or the 1000, was originally only produced as a chain final drive model (84). As the cam lubrication problem started to rear its head in 84 the immediate response was to fix the 1000 cc machine. This author's explanation seemed to say that by 85 Honda had the gear driven cam in the can for the 1000 machines and that at the same time they shifted production of the VF 1000 with the new gear driven cam over to a shaft final drive (this cycle was denoted the VF1000 R). After the fix of the VF 1000 cam lubrication problem Honda turned its attention to the 700/750 and made them gear driven cam machines. The VF 500 was first produced in 84 and it was originally a chain driven cam motor. It was changed to a gear driven cam motor at the same time the 700/750 was changed to gear drive cam, 1986. The VF 500 was discontinued as a model in 86 like the VF 1000R. It appears that the entire VF line was replaced by the VFR 700/750. My memory of the chapter is that Honda essentially switched from manufacture of VF 1000F chain driven final drive in 85 to essentially 100% shaft driven VF 1000R machines in 86. The shaft driven machines were only produced for part of 1985 and the entire run of 1986 VF 1000's and then Honda discontinued the model. The VF 1000 R was 30 or 40 lbs heavier than the chain drive VF 1000 F. Thats the story I read and I'm sticking with it until I can prove otherwise. The redesign of the big VF engine also impacted the Saber and the other Honda crusier that used the V4 motor at that time. I think that is why the VF 1000 was the first motor to change over to the gear driven cam and why the VF1000R was to end its days with the shaft drive that was put on the contemporary Honda cruisers. It was too complicated to keep so many different V4 models around. The VF 1000 became a step child to the crusier bikes that shared the same motor and a unit trans and final drive. The R model just did not have the sport bike agility. The VF1000R was a crusier in sportbike clothing and it just ended up not having a place in Hondas lineup of cycles. They had a couple of fine crusiers with V4 motors and shaft drive final drive, what did they need a similary equipped sportbike for? Honda focused on the large capacity motor lubrication problem first because that motor was used in their big gun cruiser model as well as the VF. They 'had to make the big cruiser model right or loose face to Harley and the rest of the american big bore motorcycle world. Thats why the 1985 VF1000 F and R models had the updated gear drive cam first.

 

Ok CA110, lets put the baby to bed.

I bet that if you take the valve cover off your 1986 VF 500 F you will find that it has a gear drive cam. I further bet that if you take the valve cover off your 83-4 VF 750 you will find a chain driven cam. Honda found they had a lubrication problem on the VF motors, including the Magna and the Sabre as well as the VF models. The V65 1100 cc crusier had yet to be realized in the middle of the 1980's. Honda started a quiet recall and patched the big cube bikes first. The VF 1000 engines got the gear drive cam treatment first, in 1985 and on thru 1986. These motors were used on the Magnas/Sabers which ever was the 1000 cc bike. The bigger of the cruiser Hondas got the shaft drive treatment as well as the gear driven cam treatment in 1985. Rather than make two versions of the VF1000 motor, one with shaft final drive and one with chain final drive Honda compromised and made all cycles using the VF 1000 engine adapt the shaft final drive as well. It had been built into the unitary motor/tranmission and so it went into the VF 1000 and it was called the VF1000R for shaft drive 1000 cc V4. All v4 engines built after 1985 were given gear driven cams regardless. The first V4 motors to receive the gear driven cam modification however were the 1000 cc VF motors used in Magna or Sabre as well as VF1000 R. There were some vf1000 F motors that got through the assembly line before all VF1000's were made as shaft drive examples in 86. I would guess that the rarest VF1000's are the 85 VF1000F's with gear driven cams.

 

DKC - Much of the information that you state here is flat wrong. Sorry to be so blunt, but that's the only way to put it. In fact, there is only a small amount of it that is correct. Here are some major points:

1) The 500's never had gear driven cams. Download a Honda fiche if you would like to see for yourself.
2) The R's were never shaft drive. In Europe and Australia markets Honda continued to produce the F model after 84 with some changes. This model may have received shaft drive, I don't know. The R's were not made after 86 and all had gear driven cams and chain final drive.
3) The Magnas and Sabres never had gear driven cams, I don't even think the late 80's SuperMagnas did.

Sorry man, it looks like your "expert" has led you astray in a big way!

 

I just had the valve covers off my 86 500 interceptor, I put on a set of vance & hines pipes and mufflers ( had them ceramic coated silver, almost looks like chrome) and took the carbs off and rejeted them. that is when I decided to adjust the valves since I had it that far apart, they are chain driven cams, but I knew that going in. the mod I did got me better bottom end and mid-range. also better throttle response as it had a slight flat spot off idle with the super traps on at the time, which is gone now. I just brought home an 83 750 interceptor, thats my next project, I'm gathering up parts for it now. I expect I'll have the top end off just to have a look since I don't think the odometer is correct at 14,000. does anyone know if that top end gasket set thats on ebay right now is any good?