It's a 1991 Suzuki Bandit 400.
Quote:
I just bought this bike knowing it had some some troubles. I rode it around before I bought it for a solid 15 minutes and it stalled out on me once when I pulled in the clutch lever. I stopped, put it into neutral, and it fired right back up. It ran like a champ before and after that though.
Riding it home a few days later, it made it a couple miles, when I began to lose power, I was giving it a lot of throttle just to continue going 40 mph. Finally, when I had to downshift, I pulled in the clutch, and it died. I was about to get it to start after some time. Later down the road, the same thing happened, and I had to get it towed to my house.
I went out there yesterday, and the bike started right up, and idled perfectly. I rode it around my neighborhood to see if I could diagnose the problem. Upon coming back to my house, it began to struggle, then died. I let it sit in my garage overnight, and now today, I am unable to start it. It turns over, but doesn't seem to want to fire. Occasionally, it will fire, but it will die out immediately.
I took it a mechanic and he replaced the floats on the carbs and the bike ran fine for a few miles and now it's started this crap up again. It's really irritating. I want to get out and ride it.
Anybody have any ideas.
does that year have a rectifier? when i owned my 98 cbr600 i read online that a lot of people were having the same problems your having and it was their rectifier.
part in jest but part serious as well,
ask Weebel.
titus03 wrote:does that year have a rectifier? when i owned my 98 cbr600 i read online that a lot of people were having the same problems your having and it was their rectifier.
This?:
http://en.wikipedia.org/wiki/Rectifier
It's a loss in motor power, not electrical power.
ToBoGgAn wrote:
part in jest but part serious as well,
ask Weebel.
I'm hoping he reads this thread.
easiest thing to do, check the charging system. make sure you're getting 13.5-14 volts at the battery while the bike running. check to make sure the plugs are firing. do a compression test. make sure there's oil in the bike.
Why are you people hoping I read this? LOL
My bike did that type of thing when the stator in my charging system went out and the battery would get too low.... but charging it fixed the problem... if your battery isnt getting low... its most likely not a rectifier/voltage regulator issue...
What is wrong with this bike seems to be in the carbs or a fuel delivery problem to me most likely though....
Check for manifold leaks, clean the filters, and clean the carbs out really good (could be a clogged jet or something) and see what happens..
Also.... do you have an automatic petcock? Some of those vacuum operated petcocks can go to hell over the years and not supply enough fuel to the engine (I had to bypass mine)... and if it is vacuum operated.... make sure the vacuum hose going to it isnt leaking.... (should be the first thing to check)
Weebel wrote:Why are you people hoping I read this? LOL
My bike did that type of thing when the stator in my charging system went out and the battery would get too low.... but charging it fixed the problem... if your battery isnt getting low... its most likely not a rectifier/voltage regulator issue...
What is wrong with this bike seems to be in the carbs or a fuel delivery problem to me most likely though....
Check for manifold leaks, clean the filters, and clean the carbs out really good (could be a clogged jet or something) and see what happens..
Also.... do you have an automatic petcock? Some of those vacuum operated petcocks can go to hell over the years and not supply enough fuel to the engine (I had to bypass mine)... and if it is vacuum operated.... make sure the vacuum hose going to it isnt leaking.... (should be the first thing to check)
I've checked all the vaccum hoses I could get to.
The air filter is brand new. Carbs were cleaned out when the floats were replaced.
The petcock is vacuum actuated. When the carb creates vaccum, the petcock opens up and the fuel is drained into the carbs. I've checked that system it works well. The petcock is only a couple months old.
When the bike DOES run, it runs fine through the entire rpm band, it's not until after a few minutes of riding it that it begins to lose power and eventually stall.
That still really sounds like a fuel issue..
Does how warm the engine is effect it at all?
Have you made sure you have spark at all the plugs? (when its not starting)
I thought about the petcock screen being dirty... but if it's been replaced it should be clean.
Will it fire using starting fluid?
Are you sure the carbs are jetted correctly and the mixture isnt way off?
Is the choke stuck on at all?
Electrical problems can cause this... but checking it isnt the same as on a car.... most bikes only put out enough juice to keep the battery charged (not actually charge it)
The battery should stay at or above about 12.5 volts when the bike is running.... and when you rev it... the voltage should go up just a little bit but not much.. my bike actually drops just a little for a sec then goes back up... I havnt completely fiqured out why yet (might be how I have it wired)... some bikes are different.... but just make sure its not dropping below (and staying a little above) what the battery is at when fully charged and the bike is off.
Although.... if your battery is draining enough to make the bike stall (the bike runs off the battery not the charging system).... if you go to start it again right after it does.... the battery should be low enough for the electric start to barely work if at all.... If you bike does this and dies.... and the bike cranks over like crazy immediately afterwords when you hit the starter.... I highly doubt that its a charging system problem. The battery can be pretty low and the bike will still run.
Since you said it wants to turn over fine but not fire.... it doesnt sound like an electrical problem.. (other than possibly the ignition)
Next time it dies, open the fuel cap and listen for noises. If you hear a hissing sound when you open the cap, the problem is your fuel tank vent is clogged. Fuel leaving the tank without air entering will cause the engine to starve for fuel. After is sits for a while, it may allow air into the tank through the carbs, but if the floats are new and set to the right height, that won't happen.
Lifes too short to drink cheap beer.
^^^^ yes that can happen too...
A lot of times on hotter days or in the garage if its been sitting awhile.... when you tip the bike up you can hear it vent....
The good news is that the vent is usually in the cap so not a big deal to replace (asuming you can find one for that old a Jap bike)
Theres a good chance that what green98 said could be your problem... (never think of that because it hardly ever happens LOL)..... if you cant hear anything..... make sure theres not a lot of gas in it and ride it around with the cap off and see if it still does it. (and no...... riding the bike without the cap wont hurt it any... just make sure the tank is low enough that gas isnt splashing out all over you)
Good luck and let us know...
