Strange grating noise on the downshift (video)

[maccas]

Hi guys,

Recently took my newly acquired fzr 400 rr 3tj1 to cadwell for a trackday. The bike handles lovely, not the fastest thing in the world but it certainly makes up for it on the brakes and in the twisties.

A couple of noises developed during the day. One was a ticking noise which you can hear in the video which I traced to leaky headers so that's nice and easy I've just welded up the cracks until I can source a full system for it.

The other is a horrible grating noise on the downshifts and overrun. You can hear it especially going into the bottom of the mountain, Mansfield and park corner:

http://www.youtube.com/watch?v=RWCymFvFhUY

I'm thinking it's the camchain. Any thoughts? Anyone else experience this sort of noise before?

Oh and the boggy ness on part throttle has been since sorted. The airscrews were set at 2 turns out instead of 2.5. Much better now :-). Back at cadwell this Sunday.

Any help appreciated before I strip it at the weekend!

Cheers,

Dan

[Evilchicken0]

It does sound like the camchain ... check the tensioner springs are ok and clean it. You probably know that already, by your lines you look like you've been around there before

[maccas]

Hi Buddy,

Thanks! I will check that out! Can I convert it to a manual adjuster if need be? Has anyone done this before?

Cheers,

Dan

[Evilchicken0]

You can do, but I haven't heard many people doing that.

Checking the tensioner is the first thing to do after that you might need a poke about a bit (technical see). Might be an idea to have a listen to the engine with a stephescope or use a long screwdriver (as long as the blade goes through the handle). Touch the engine in different paces to find the area where the noise is.

Check the exup is opening and closing properly too, this is more a service thing, take off the chrome cover on the exhaust the pulley has two prongs which sould be either side of the hole in the casing. turn on the ignition and it should cycle backwards and then forwards. Look at the cables to make shure they're not frayed, the cables should be finger tight only.

[maccas]

Ok cheers. It doesn't seem to make the noise when the engine is running in neutral. Or when winding it on through the gears either. it only does it on the overrun at high revs.

The exup cycles fine however it does rattle it's head off at standstill so it could well be that too. I'm currently making a new set of bushes for it as we speak.

Thanks again for your help.

Cheers,

Dan

[maccas]

Checked the camchain yesterday all seems well there.

I think i have found it! The front mudguard!! It wobbles and makes a rattle and it sounds just like that in the video. I'm going to tape it up and try it! Fingers crossed!

Dan

[Evilchicken0]

That's good news