Matt Tries – 1984 VF500F Overhaul

This is something I've been wondering about for the last couple years but never knew where to ask... I always read that "Tires go bad after 5 years" and "If you ride on old tires, you'll most certainly be killed."

Is this just a safety thing that's passed on to keep people from firing up a barn find CB350 and jumping on the highway with 45 year old rubber? Is it like the "One gallon per inch of fish" rule for aquariums to keep people from buying 9 goldfish and keeping them in a 10 gallon aquarium?

I understand that the properties of rubber undergo a change with time and usage. Hell that's why I'm trying to replace everything rubber right now. But I was looking at straycat's pictures earlier of his beautiful bike gallery, and I was thinking there's no damn way people replace tires every 5 years on those bikes. You'd need to hire an assistant!

I'm not a terribly quick rider. If I was pushing limits, I'd be far more concerned about tires. And I had a scary moment on the Bandit because that front tire is wasted, so I know old/worn rubber is scary. But if the tires have 2,000 miles in 5 years, are people replacing them if the bike doesn't see the road often?

 

5 is too conservative for me, but it depends on which bike we're talking about too. My modified VFRs taunt me too much for old tires. On some of my bikes though, I will adjust my riding accordingly as long as the tires don't feel dangerous. I know I can't account for surprises where the perfect tire might make the difference, and I realize that. Plus my bikes live out of the sun in a climate controlled environment, which helps a bit.

I guess I don't have a "number". But I know when it's time for me.

 

Yea, really depends for me too. If the bike has been stored in side, heated storage etc (all mine are), and the rubber isn't hard as a rock, I'll certainly go beyond 5 years. My NS400R had new tires 4 years ago, its not done 20km since then. Next year will not be the year I replace them. My 2014 VFR800 tires re like new still (3200km) theyre not getting changed this year either.

On the other hand, the 2003 Kawasaki Z1000 I just got has only 2,500km on it, and is all original, including the tires. and while they're not hard at all, Ill still be putting new rubber on it before it get on the road.

Im also not an aggressive rider, so I really dont intentionally push my tires to the limit, but that doesnt account for any emergency and evasive action we all have to take from time to time..

 

Thanks guys. I really do appreciate the insight.

 

I think some manufacturers say 6 years now, but yes, keep them out of the sun and if you see any cracking best replace... but I know guys that have run 20 year old cracky tires and had no blowouts.

 

Rode this to work today (pretty much how I can enjoy my bikes now). 1973 SL100, 1890 miles.


Original tires.

Are they cracked? Not really (amazingly).
Are they hard as a rock? Fuck yes.
Do I care? Fuck no.

 

FUN FUN FUN FUN

 

The thing revs to the moon and keeps pulling. And it is FUN.

 

Ohhh that thing is neat. I don't think I've ever even seen an SL of any displacement in person. At least, not since I've taken note of what they are. How quickly can you get going on that bike? Legal with no turn signals? I'd guess yes, actually... I need to find some 6V LEDs that work.

Once it gets a little warmer than the 30s it's been in the mornings... This whole little pandemic has opened up the roads enough that I might have the stones to ride my little KE100 to work. It doesn't quite go 55mph, but I need to take 55mph roads to get here. But with the lesser traffic, I wouldn't be as much of a nuisance. It sounds like I'm riding a weed whacker, it's hilarious.

Also relevant because these were the first tires I ever changed by myself. Did it last winter.



Anyway, I think I have a hunch on what is causing me so much trouble with getting my front brakes pressurized. If it's what I think it is, then I might just keep it to myself or risk having my license to carry a screwdriver revoked.

 

It's geared a little low, but around 60. The thing screams. They had turn signal "kits" you could get. It has the wiring and handlebar switch.

Did you install the cup backwards on the master?

That KE is super cool. I'm selling all of my AR80s soon (when me and the buyer can actually meet). The motor is real similar.

 

LOVE IT. !!!!!!!!!!!

 

I'm second guessing myself on the cup orientation... and also my initial worry was that I somehow installed both the cup from the old one and the rebuild kit somehow. I used way too much grease the first time, so i thought it might have clogged the spiral path, so no fluid was flowing. I ran the reservoir through the ultrasonic bath again and cleaned everything out. I also know for a fact that I can push fluid all the way through the top banjo from either bleeder.. so long as the master cylinder isn't connected.

This picture was taken prior to re-cleaning it.


So I'm nearly certain my problem is somewhere on the master. I'm getting a couple bubbles every now and then when I pump the lever. I've just left it open and give it about 100 pulls every now and then. Will hook up one of the old brake lines to the master and see if I can just pump fluid without any resistance this weekend.

I've never heard of the AR80. The wheels on that thing look awesome. I'll need to do some reading on those!

 

Does anybody know if it's possible to just buy a throttle linkage bushing? Or if these are standardized across any Honda or other bikes? I've finally finished reassembling my buddy's carburetor with a Billy's Outback kit, and this appears to be the one piece that I couldn't locate.

It's looking like I might have to find a place to buy the full linkage which kinda stinks. I assembled the carburetor anyway because I wanted to know if it'd hold fuel and if it could work without it... Well, it holds fuel! But it sure as hell won't synchronize without it.

The good news is that I learned you can get the throttle linkage off without breaking apart the carburetors again (whew). I was thinking the whole thing was going to be coming back apart.

 

does billy's not sell those separately ? I know he sells sync springs and other small bits as separate items, ive bought them.. may be worth emailing him.

if not ill take a look to see if I have a spare one kicking around, you can have it for the cost of mailing it if I do.

 

Emailing Billy's is probably the exact thing I need to do! I didn't think of that. I can't find them listed on his site, and they're not part of any of his 500 kits, but I bet he knows where to get them (or has them for purchase). I appreciate the offer--if I exhaust my other options, I may take you up on it.

 

I'm pretty damn near my wits' end with this master cylinder. I've watched 20 rebuild videos and tried everything I can think of, but I can't get it to pump fluid. It will not exchange brake fluid for air. It has the ability to build pressure, and I verified this in a couple ways; however, it's behaving as if the seal never retracts beyond the fluid intake, so it can't actually exchange air for fluid.

I am able to back bleed the system with a syringe through the entire brake line system from either caliper bleeder no problem. Loosen the banjo on the MC and inject brake fluid, and it'll come right through. I then hung the calipers off the handlebars to try to remove any additional air bubbles. I pushed the pistons in with C-clamps all the way, and I actually had a stiff brake lever! Bled the system like that, and it felt pretty good. As soon as I put them back on the forks without anything impeding piston movement, it went completely limp. So this plays into my theory that it's not air in my system that's causing these issues; but rather, it's the master cylinder not able to exchange air for fluid. It just moves the pistons in and out equal distances.

I used a 4into1 rebuild kit. Again, like an idiot, I tossed the old rubber seal, so I can't test against it. I do have the spring though, and it looks the same as the rebuild.




This doesn't seem like one of those "sleep on it, and the answer will be clear in the morning" type deals to me. I've been at this on and off for weeks now. My next plan is to pull the master cylinder off my FZR and see if I can get it to work on the VF500F. I have an R6 MC I've been meaning to put on it anyway. If I'm able to get brake pressure with the FZR master cylinder, then I'll know my issue is with the rebuild kit and not a bigass air bubble hiding out in the brake lines somewhere.



This is more of me venting than anything. Hopefully I can laugh at this later once I figure it out.

 

i did once install the master cylinder seal backwards - could not get pressure. could bleed but would not get pressure.

 

Suggestion..... pull the lever to the bar and zip tie it there, leave it overnight... air will rise to the top. In your case with little/no pressure, may have to do it more than once. Perhaps get back to the conditions you had with good pressure, then zip tie it. I can't remember all you did, but suggest the rebuild kit, a slightly swollen rubber may be blocking the return port.... give it a shot, see what happens. Frustrating I know.

 

I feel for you , I really do. Ive been F'n around with my RC51 brakes for a while, and its frustrating. I admire your tenacity.

 

I did hear once that sometimes the pistons can stick in the bore of the calliper and when they dont move freely and get sticky it can create a soft lever ( I suspect this is the issue with my RC51).

I wonder if you have the same issue, by pushing the pistons back with the C-Clamp and eliminating that piston movement you eliminate the problem. take the clamps off and your problem returns (?)