Jim's $400.00 1986 VF500F

Rode the vf400 & the cbr. Cbr won hands down especially in the wet.

 

I also rode both the VF500 and CBR600 brand new and I have to admit the CBR600 was a really nice bike and possibly better than the VF500. BUT....since it was a new bike I never got to push it hard just up and down the street to test ride it for putting it on the floor. I did get to ride the CBR1000 also and I thought it a pig, though I never got to ride a VF1000R so I have no idea how it compared. We could not get the owner to order a VF1000R because we had a hell of a time selling the (1) (84?)VF1000F Interceptor we got. I think it sat for a year or more before we sold it off the floor.

Had not thought about this stuff in ages....Memories!

 

I rode a friend's vf500 for a day back when I owned a '85 VF700s "Sabre". It was two years between that and when I purchased the first CBR600F model in '87. I owned and rode the "Hurricane 600" for five years before selling it. I hated having to sell that bike.

Hard to remember that far back, and a two year compairison.... What I do remember is that the VF500 was a lot lighter than my "Sabre", and the "Hurricane" was a lot lighter also. The power was noticeably less going from the 700 to the 500, however, the difference in weight from the 700 to the 600 was very noticeable and the power seemed to be equal between the 700 and 600. The V4 power bands are wider and the CBR was a lot of fun with the RPM's in the upper scale. That being said, the CBR 600 was "buzzy" below about 7000 RPM and smooth above. If I had to choose between the two, it would have to come down to track bike or commuter. My opinion would be the CBR600 to be the track bike, in large part because the chassis is very stiff using the engine as a main part of the frame. The VFR 500 would then be the commuter of the two because it's wide power band is better suted for around town riding (but only slightly).

 

Yeah the CBR600 was definitely the bike of choice for the track back then. The Kawasaki Ninja 600 was the bike everyone had at the track previously and the CBR600 I thought blew the Kaw away. I did see several people racing the VF500 though and it did OK until the straightaways. The 600's ate it's lunch on top speed, hardly surprising. There were so many CBR600's out there being ridden by novice riders in the late 80's we actually stocked body parts for them they got crashed so often!

 

The CBR600 was a huge success in the UK. Honda then developed it and definitely pushed the quality up as the years passed. Sort of single handedly made the sporty 600 class a thing, although I think the GPZ600R (Ninja) preceded it.

 

Back to the overhaul!

Go the pivot axle from the swing arm finally removed, it took 2 days of soaking in penetrating oil to be able to punch it out. Surprisingly the needle bearings in the pivot points were still ok.



I also ended up having the correct lubricant on my shelf. Not sure where I got it but glad I had it. MolyKote G-n from the Helms Honda manual

 

It Lives! Got it back together enough to start it with an auxiliary gas tank. It smoked pretty good for a bit but it actually settled down to a 1000 or so RPM. with some barely seen smoke. Hard to believe it is running on less than 100 PSI on the cylinders. I idled it for about 10 minutes and the smoke got way less. I did notice some blow by smoke from the crankcase hose but it was not bad. I guess I will just keep moving on this restoration and just live with the engine compression for now. The radiator fan came on also so that is good. YAY!

 

Don't get caught up in the "numbers". If it runs good, it runs good. You'll know after the first couple rides. Get some miles on her and bet she doesn't smoke or blowby at all. Then do another oil change and ride.

But always keep your eye out for that spare engine deal.

 

Steady progress, rebuilt the carbs (again) and got the fuel petcock working.

Billy's Outback for the carb kit was a winner. all of the orings were spot on. His price was also outstanding.

Here is what the petcock ended up looking like:


I used the gaskets, screws, and filter from the $8.00 Chinese petcock I bought off EbAy. The screws were M3 x 0.50 thread but were really short, maybe 5mm. I was barly able to thread the petcock enough to get the screws to bite. Not sure this is going to work out but it did not leak on the bench all weekend so I am going to give it a go.

Also....made a temporary fuel system to run the bike. Put about 45 minutes on it and it is still smoking but seems to be getting better. I ran it through the gears with the bike on the centerstand at low RPM and all gears seem to be present and accounted for.

 

have you inspected the valve stem tops for problems yet ?

 

I have not, I did adjust the valves per the Helms manual and they sound OK.

Is there a thread that goes over this valve stem issue? Not sure what to search for.

 

There's a service bulletin about it somewhere if you search. In my experience I think it was probably overblown. Dropping valves is a much bigger issue unfortunately.

 

but isn't valve stem damage the biggest factor leading to dropped valves, ya think ?

 

Here it is. Maybe connected but in most of the examples I have seen, the valve head separates along the stem. I did hear of them fracturing near the keepers but I haven't seen an example of this.

 

ultimately, the failure is due to valve float and piston top contact at high rpms caused by bad springs, innit ?

 

Really your guess is as good as mine. There are plenty of high mileage VF500s out there so valve drop doesn't affect all. I stopped worrying about it ages ago and I thrash my engine whenever the mood takes me. I definitely don't bother with the 9k limit. There's no evidence it makes any difference keeping the rpm low, but I can understand why some might think it would help with longevity. IMO the best thing you can do is make to make sure the engine runs as cool as possible. A working thermostat and fan switch in conjunction with good coolant and a clean radiator is much more important than a RPM limit IMO.

 

Very interesting read, thanks for going to the trouble of finding this. I do not remember this being a huge problem when I worked at Honda in the 80's but again we did not sell a ton of the VF500F or VF500C Magna models .

Now the VF700/750 Sabre and Magna....Wow those had MAJOR issues with the cams and followers. We did a bunch of warranty engines on those. Honda reached really far on especially the VF750 Sabre when it came out and it was FULL of bugs. The instrument pod was an electronic nightmare in 82 but it sure was cool.

Strangely we had some 750 Sabres that had no problems at all.

 

Valve float at extended high RPMs leads to mushroomed valve stems and then eventually a dropped/sucked valve. Friend did it twice on his 84 500 in the day (84's do not have a rev limiter). Found a mushroomed valve stem on my 500 race bike (shocking) 2 nights before a race. Borrowed a RS125 (FUCKING MAGICAL) that was legal for my class to get points (won the championship a round early that year) and then swapped in another motor for the final round (86 out, 84 in). 84 sounded way more wicked than my 86 but never bettered my best lap time with the 86.

 

Back on task again... going to try out the "Diving Pete" process on the rusty tank...wish me luck!

 

I really don't like acid treatment on tanks. Or anything I care about, really. Electrolysis is far better, turning rust (and *only* rust) into a mixture of iron and a non-reactive iron oxide without touching any base metal. It's close to the opposite of rusting. The chemistry is a bit complex, but it turns Fe2O3 (ferrite) into Fe3O4 (magnetite). One's highly reactive, the other one is pretty much passive.

Positive aspects - doesn't reduce thickness of material beyond removing the actual rust, doesn't require neutralisation afterwards, doesn't require manipulation and disposal of dangerous chemicals, it doesn't matter if you leave it running too long.
Negative aspects - you need to be careful about polarity (or you *will* remove material), you need a battery charger or other DC source, produces hydrogen so needs to be done in a ventilated place, you need to clean the sacrificial electrode occasionally, which is a bit gross to do but, health-wise, inoffensive. There's a potential for "hydrogen embrittlement" of spring steel pieces, but that doesn't really apply to fuel tanks. Any remaining paint in contact with the solution is liable to be removed (the process forms hydrogen bubbles under it, lifting it off), and you need to remove all aluminium or brass pieces, they *will* get eaten.

Once you've scrubbed off the magnetite, the base metal can and will rust afterwards, in the same way it will after an acid treatment (although it won't "flash rust" in the same way).

I use electrolysis for rust removal on precision pieces - lathe parts, collets and the like, the results are nothing short of stunning. Example:

Before:


During

After :

These have been quickly rubbed with a bit of scotchbrite


… And this is straight out of the tank. Note the rust has been turned to a blackish, neutral and non-reactive, oxide. Even left like that it won't re-rust.


Repainted and assembled: