bike making a ratling noise

hey just got a 98 model wr400 about 1 month ago, today while riding the bike i notice there's rattling noise coming from the engine is it something to do with the camshaft ?? thanks for your time

Could it be the chain slapping on the swing arm?

Is this your 98 WR400 that you just got back, or did you just get back into motorcycling and this is the bike you purchased? Yamas are notorious for being loud. There have been a number of threads on TT of Yamowners discussing how much noise their bikes make and how this is simply a fact of Yamownership.

Now, could there be something wrong with your bike? Yes. However, you might have to give a little more detail to get some answers.



the noise is coming from the top end of the engine where the cam is, if that's whats it's called sorry for the lack of detail

Check, or have someone else check, your valve clearances. On a '98 model WR things might be getting a little tired. Could be cam chain. Could be a lot of things though. As Bamster said, the drive chain slapping the swingarm can often be mistaken as a mystery engine noise.

So we are safe to say that the noise is there when you are not moving.

As Chris said check the valves, they could be tight. I have never seen them get so tight that they click but Dan L has. While your in there you will be able to see what condition the timing chain sprockets are in. Do you have a manual?

If so follow the instructions on valve clearance inspection and shim replacement.

It's really very easy,so don't be afraid to tackle it. The dealer will over charge you for this job.

Your only problem will be not knowing what shims are under the buckets.

If you are out of spec ,you will have to remove the cams and buckets to get the shims out. Then order the new shims and wait for them to come in. There is a chart in your manual that will guide you for what size replacement shims you will need. You will have different shim sizes so the smaller ones can be reused elsewhere.

VERY IMPORTANT as you take out each shim right it down, what size and where it came from.

ok thanks for all the advices will get it check soon thanks alot

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