problem idling

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kpf

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o6 has a problem idling some times. I just bought the bike about a month ago and it would some times stall at a stop. the miles was at 25800 and after riding it for awile it came to 26600 and i did a valve adjustment. after completing the adjustment it now started experiencing low idle again. the adjustment is all the way up. does any one have any suggestions on whats going on ?

 
Sounds to me like there is a good chance your cam chain timing is one tooth off. I saw this Fairlaner's 08 FJR. After performing a valve check it wouldn't idle, but ran great otherwise. Turns out the cam chain had skipped one tooth on the crankshaft.

 
You say that the idle adjustment is "all the way up." What is the warm idle speed rpm (when it isn't stalling)? If it is anything less than 1100 you may only need to raise it further. Many a second Gen owner has cured all sorts of idle problems and stalling simply by raising the idle speed to 1100.

To do that. since you already at the idle adjuster's maximum, you will need to lift the tank and open each of the four throttle body air screws (the ones that you adjust during a TBS) an equal amount, say 1 turn each. This should put the idle too high and will allow you to use the idle speed adjust to bring it back down. You will then need to re-balance the 4 air screws to each other (perform a standard TBS). No need to worry about using #3 as the reference, just lower the high ones and raise the lower ones to match the means.

If you get that straightened out and it is still stalling it may be worth investigating the cam timing.

 
If it had a good idle before you took it apart and will not idle now, then my guess would be that the timing is out. Bite the bullet and check the timing. You are not the first to put it together wrong.

 
...and he DID say "Valve Adjustment", not "Valve Check" which implies cams came out, so the likelihood of mistimed cams ranks up there around 98.3%.

 
Believe it or not my bike was out by 2 teeth on the cam. Ran strong but wouldn't idle.

 
You have NO idea how lucky you are you didn't air-mail a set of valves!!!
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I hear ya. And I did the big trip around the continent with it like that. She's tickety boooo now

 
I'm wondering if Michigan, Superior, Ontario or Erie had anything to do with the borked valve adjustment?

Some kinda great big hole in the ground full of wet stuff!
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I refuse to throw anybody under the bus. I take full responsibility for it.

 
Believe it or not my bike was out by 2 teeth on the cam. Ran strong but wouldn't idle.
FYI... Being off 2 teeth on a cam sprocket is exactly the same amount as being off by 1 tooth on the crankshaft sprocket, which is the most common situation when slackening the chain tensioner and not watching or securing the lower chain position.

If you were off by 2 teeth on the lower sprocket, I'd wager that you'd be valve shopping right now.

 
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I really apreciate the help thanks. Warn up idle is above 1100( probably 1300 ). It has a short time between the bike raising temp and it seems to have hard time to idle, just below a 1000. When the temp is warm it idles at a 1000. I will check the timing and go from there. I'm sorry what is TBS ? No subsitute for doing some research, anyway thanks again

 
Idle at cold start should be @ 1500 RPM. Once engine is warm, idle seems best @ 1100RPM, but it can be a bit faster or slower depending on how hard you've been riding/outside temp/idling in stop and go traffic.

As suggested above, bump up your warm idle to 1100, and see if that helps.

TBS = Throttle Body Sync

Fred W has excellent instructions on the RDCUTBS, which I fully endorse

 
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