Just bought 92' FZR 600

[Lorenzai]

Well I have a more pressing issue than tire preference. My throttle is getting stuck / not returning to idle. Luckily this happened when I was warming it up today. Scared the living shit out of me. I pulled apart the throttle control on the handlebars. The throttle / return cables are there and look like I would expect. I didn't notice any way to adjust the return tension. Is it on the handlebar end or somewhere else?

[willandrip]

If you look at a parts fiche your questions are usually answered.

The adjustment for the return cable is at the carb bank.

If either cables are adjusted with insufficient slack then the throttle will stick, but particularly the return cable must have a little slack.

Ensure it is not the twistgrip rubber preventing closure.
Usually this problem develops over a period, becoming slower and slower for the cables to close ;indicating lack of lubrication.
If it was suddenly I would assume that perhaps the cable is beginning to fray and a strand has jammed or the cables are incorrectly routed.

[Lorenzai]

I checked the rubber and its not that. I think I know now what's wrong with it. The linkages all look to have good tension, but I think it was because the throttle grip was being put at a weird angle and contacting the start/ run controls. The handlebar is bent!. Also-When I was checking out the carburetor end of the cables to make sure that they weren't binding I made a wonderful discovery. The airbox wasn't even connected to the carbs, so they were just sucking unfiltered air. That's strike one. Then I made an even bigger discovery. The carburetors themselves weren't even bolted on. They were just sitting on top of the tubes that they're supposed to be inside of. That's just crazy! I'm not sure how it could even run like that but I'm just blown away. Everything is now suspect on this bike. I guess I'm going to have to go over every single nut and bolt!


Sent from Windows Phone 8.1

[Lorenzai]

I got the carbs seated and clamped down properly. Put the airbox on the bike, got the tank in, got everything buttoned up. Started it up and it definitely runs better with the airbox connected. My elation lasted all of about 30 seconds before the bike started pissing coolant everywhere. Its one of the twin coolant tubes, the one on the left side. I replaced the o ring and started it back up, STILL leaking. So I had to take the plastic tank cover, fuel tank, airbox, and the carbs all back out again to replace the rubber coolant line. Talk about frustrating! I don't know why I expected an $800 bike to not be a pita but I did for some reason. I know better now, ill tell ya. Its like the more things I fix, the more things break.

[willandrip]

Most owners go through a period like this with new ownership.
It takes time and newly learned skills to eliminate the problems of a unmaintained motorcycle.

Very rare to buy a top notch bike cheap from a meticulous owner.

Your getting there bit by bit.

[Lorenzai]

So the bike runs much much better at low rpm. All the torque I could ask for. I'm still experiencing a problem with the bike though. The bike will only rev to 6k rpm and its like I hit a rev limiter. I can't tell where the problem lies as of yet, but I really dislike this issue. I'm going to check the plugs for rich or lean conditions as well as measure the gap. I've heard from multiple sources that .030 is the sweet spot on these bikes. I will replace the fuel filter too - just in case. I will also check the voltage regulator tomorrow as well. This bike is angry at me for removing her from her slumber. She's only averaged 380 miles per year for over two decades

[willandrip]

By any chance have you cleaned the jets in the carbs ?

If not......debris/scale may be causing an obstruction.

It is more usual that the bike fails to start or idle with the above though as the smaller jets that block easier are in operation at low throttle openings.

What does occur fairly regularly though is; the main jet and the starter jet are mistakenly transposed when replaced and the engine cannot get enough fuel to gain rpm. The 2 jets are adjacent and fit into the incorrect drilling with ease.

[Lorenzai]

I have not had the carbs apart for a thorough cleaning but.. I did dump a bottle of Berrymans Bchem in the tank. When I first noticed this rpm limitation it was 8k rpm. It seems to fallen to 6k rpm now. I will say that I have no clue how old the gas in the tank is, so this could be part of the problem. I want to note also that in neutral the bike will rev right on past the 6k-8k range probably all the way to redline.

*edit* I went out to the garage and checked my fuel tank. My gas is GREEN. I'm not making this up.Does b Chen turn gas green? If it doesn't, I think this might be indicative of an issue.

[Lorenzai]

I rode the bike for 70 miles today. Even not being able to really rev it out I had a blast. When I got back I tested the voltage. My battery is nearly 13 volts sitting with the ignition off. With ignition on but not running it drops to 12.5v. With the bike running at idle I'm getting between 13.4 and 14.0v. When you rev it up a bit the voltage drops off to around 13.5v. So I think my stator and VR are okay. I also noticed that my tank petcock has been on reserve the entire time. So that might be playing into my problem if its skimming all the crap off the bottom of the tank and clogging up the fuel filter.

[Lorenzai]

Well I'm 90% sure that my issue is a fuel related issue. The stuff I pulled out of my fuel tank is the worst I've ever seen. There I a lot of rust in the tank. I really don't know what to do about it.

[DonTZ125]

Do a search here and on Google for tank rust removal. Also - these engines run on gasoline, not swamp water!

If you haven't even changed your fuel, that sure suggests to me that you haven't changed your oil, filter, coolant, or brake fluid. Those are all just as critical to the operation of the bike, and probably just as contaminated!

[Lorenzai]

He had just changed the oil before I got there with yamalube and a Yamaha filter. I have already changed the coolant due to blowing out one of the coolant tubes. For some reason I never considered the fuel before. One of those things you take for granted. Here is a pic of it in a powerade bottle.
Thank (insert deity) for inline fuel filters!

[4wred]

One of the first thing's I usually do when I get a new bike is that isn't running or running incorrectly is to pull the tank,drain the bowls,replace fuel filter.Then I try to run the bike with a external fuel source.Takes all the guesswork out of the equation,as far as fuel delivery problems.The condition of the fuel you drain out of the bowls can tell you alot.I don't take the P.O.'s word for how long it's been sitting.The condition of the gas in your'e pic looks bad,I bet you have clogged up jets and passages in your carbs.A bike thats as old as your's with only that many miles on it suggest's it has sat idle alot over the years.

[Lorenzai]

Yeah I know that...now. That fuel was bad bad bad. Here's the problem now. I tried to strip the tank to remove the rust but unfortunately the fear I had came true. The inside was rusted bad enough that the stripper left pin holes on the bottom of the tank. After blowing the tank out with a compressor the inside had flash rusted almost instantly. So my plan now is this. My friend works at a dealership and he's going to tig weld the holes shut so that the tank is useable. I'm going to just use the tank as is, rust and all, until I can locate a better tank. He says he can weld it well enough so it will last thru the rest of this riding season in Ohio, then I can pull it out and throw it in the scrap heap. The tank can't be restripped and coated on the inside, its just not saveable long term unfortunately. The seconds i had the bike running, the throttle response was very different. I am hoping that this was the problem.

[willandrip]

I think you will find a good replacement tank cheap enough once you start sourcing .

Very rare for one to be damaged in an accident....it will just be a matter of finding a relatively rust free example.