weird rattle

Hi all,

A bike runs well but rattles when it warms up. The valves are checked, OK. The cam chain tensioner is adjusted and is OK. What else might it be? Mixture?

Thanks for your help,

Aaron.

 

my 750 does the same thing until it warms up.
thought it might have something to do with starter.
starts fine.
Thought matbe exhaust collector.
dont know.

 

Mine does the same exact thing. Almost sounds like something is loose. I thought it was a loose exhaust mount the first time I heard it but ended up being the cam chain. They stretch from use just like a drive chain and get to rattling around. And mine stops when the bike is closer to operating temp. You can replace the cam chain and it shouldn't rattle any more... but so far it hasn't been harmful to me at all.

 

is that a hard job?

 

If you know how to use tools and can follow directions well then it is not hard but time consuming

 

It shouldn't be too bad if it has a link. All of the cam chains I have replace in the past, have been a one piece and you had to remove the crank to change them out.

Just be sure to align everything correctly, and slowly roll the engine over a couple of time, recheck alignment, before sealing everything up and running.

 

Primary chains tend to rattle with age. My 750 has a bit of primary chain rattle at idle. However, they'll run pretty much forever like this.

 

mine only does the rattle in cold weather start-ups,and only for the first few seconds.
when it first happened last year i nearly $&^%# my pants.
i figured it was the timing chain.
never hear it in warm weather.

 

Have someone help you do a Manual resetting of the Cam Chain Tensioner.
Do it warm.

Pull the Plugs and remove the Left Side Crank Cover.
Use a 17mm Wrench on the Flats of the Rotor on the Crank.

Turn-over the Engine by hand.
Steadily turn the Crankshaft in the Engines NORMAL Rotation 4 times.
Gradually slow to a stop.

Here's where the helper comes in.
Have a helper use something like a Hammer Handle or a Wooden Dowel and "Drum" >(Tap quickly and smartly)< on the Hex Head end of the Tensioner while you perform the reset.

The reset done by presenting the Slack in the Cable before the Tensioner allowing the Tensioner to move taking up slack.

With the Assistant Drumming steadily, ...

In a swift motion, ...
Turn the Engine over in the REVERSE of its Normal Direction.
The Crank will be turned Backward.
The Chain Slack will gather between the Crank Sprocket and the Intake Cam Sprocket right in front of the Tensioner.
The Drumming will likely conceal and noise from the Tensioner.
You might hear it "Click"

Do the procedure two or three times to "Find" other slack not presented in the first resetting.

 

sweet, thx rick.

 

YEs, thank you very much.