camchain tensioner assembly

[silicon_toad2000]

ok I have looked at the manual, it says the camchain tensioner is automatic and does not need adjustments
how does it work.
Also I checked my V and there seems to be an assembly (looks like what is in the manual) on the rear cylinder, but the area on the front cylinder seems to just have a cap, is this normal? and It does not look like there is room under the cap for a tensioner the same as what is on the rear cylinder.

[jasonm.]

Look carefully there are tensioners on both cylinders. Just in different locations. The tensioner is an "anti- reverse"(ratchet) type. There are teeth inside that only allow movement one way. I don't know how else to describe it. If you have a Yamaha manual it does show how they are put together.

[EH]

The heads are designed to be used front or rear and are machined identically. The cap you describe is used in place of a tensioner assembly to cover a bolt that secures a cam chain guide. They used the same machined area to perform different functions for the cam chain.

[silicon_toad2000]

ahhh there it is hiding inder the radiator hoses. sneaky sneaky.
how long do these cam chains normally last before they are stretched beyond the service limits?
What sort of mileage do you guys have before you have had to change them?

[Paul_Jungnitsch]

I'm assuming that's what went on mine last year at 83,000 km. I was driving along in a city and the bike lost power, made some strange noises, when I tried to restart it the rear cylinder caught a few times and then it locked up.

I'd take the engine apart but I'm going to university and have no access to a garage, I'd replace the engine but the wrecker wants 600.00 US for a used one! Being as I bought the whole bike with 7000 km on it for 1100.00 in 1987, it just doesn't seem right.

Anyway, it had been making a metallic rattling sound from the front cylinder for a while, I'd assumed it was the starter clutch and had checked it just before the last fateful trip but it had turned out to be solid.

[silicon_toad2000]

Paul, did the rattling sound happen all the time, only at idle, or only when you revved the engine a little?

[Paul_Jungnitsch]

Arghh, trying to remember....at idle for sure, I think it was worst then and smoothed out with more throttle. Don't think it was really noticeable driving around, which is why I kept driving it. That said, my memory could be playing tricks. It could be that it stayed a fairly constant noise that was drowned out with increasing engine speed.

I had no idea of how to easily check the camchain tension/tensioners or if the guides, etc were doing their job. I guess now with the motor apparently shot I could unbolt the tensioners and see what's there.

[silicon_toad2000]

thanks for dredging up the memories Paul.

got the old girl started and turned up the throttle stop until the noise just started, it sounds like the front cylinder cam chain... well it's definately on that side of the engine.