Take off rattle!!

[cbrnoob]

Hey all!!! Bought a 1992 ZXR last friday and to say the least its an absoulute animal coming from a cbr 250
The problem II have is that their is a vibration coming from what I think is the engine when i take of and give it a bit of acelleration!
The rattle is happening around 2/2500 rpm. The rattle also occurs when the bike is revved up standing still at around 2000rpm.
Ive susupected the cam chain as the bike has 33,000 miles on it but i am not really sure
Anyone have a similar problem to this ???????????

Cheers all!!!!!!!!!!!!!!! Jonny

[RedexRobB]

Is the sound coming from anywhere in particular on the engine? If its coming from the right hand side, then you could very well be looking at the cam chain making the noise. Doesnt mean the chain needs doing, the cam chain guide could be worn.

One way of telling is taking the little round cover off the right hand side, you will see a little rod, how far up that is, is indicative of it needing doing. See pic, little rod on left side. This needs changing on this bike, but like say it could be the cam chain it could be the guide.

[cbrnoob]

Cheers for the help!!!! Im gonna do a spark plug change this weekend so i will whip off the cover and have a look!!!! Will I need another gasket fo the cover or will the old one be fine as their is no oil running though their??

[Tirpitz]

The old gasket will be fine.

[cbrnoob]

Update!!! I did a bit of research this evening and found that the grinding noise when revved up stationary at 1500rpm goes away when the clutch lever is in
Now i know that these bikes have a noisy clutch but this noise is definately not suppoed to be their!! Would it be my transmission thats giving up

[cargo]

Methinks that yet agaion the dangerous of trying to diagnose rattles and noises via a web forum are highlighted by this thread..



The only way to do this for certain sure is for someone who "knows" to actually listen to the bike

[gavinfdavies]

or try my tactic...

i've got one good bike at the moment, the other has a blown HG...

So I'm riding to work, about 20 miles from home, 100 miles to go, and little spare time. And suddenly I get a ticking from the engine, bit curious I keep on riding, suddenly ticking gets really loud. Oh crap, have a drop a piston ring, has something gotten into a cylinder, has part of a valve come off?!

but seeing as though fixing it will not be easy, it's still making power, and i've got breakdown, i thought sod it, i'll keep going, and i'll find out what it is depending on how it blows up!

and about 1 mile later........

....... there's a click, and the ticking stops! I think is was the cam chain getting a little loose, followed by the tensioner taking up slack. No problems since.

My advice, seeing as though fixing/diagnosing said rattle is gonna be tricky, is just ride it as usual and wait to see what breaks!

[cargo]

..................and go from a minor issue like a camchain rattle to a completely destroyed engine.

Brilliant logic I love it

[Tirpitz]

So what you're saying is if you have a problem and you're not sure what's causing it keep going until it becomes blindingly obvious by the major state it gets into eventually. Or, it might just go away.

Not sure I'll be taking that advice Gavin

Surely if you have breakdown cover it's a no brainer. Stop, ring 'em up and get a lift home where you can investigate it. Now if you were saying you didn't have breakdown, and were in the middle of nowhere, I could follow your line.......

[gavinfdavies]

ok, lets look at it this way - gpz engines cost about £100 on ebay. compare that to the cost of a camchain change etc. If you can afford garage rates, you could end up spending more trying to get a rattle fixed (splitting cases, measuring gear free play etc) than actually fixing it when it goes wrong. Say the cam chain on mine did go. buy an ebay motor and cannablise for parts. If i'd run off home as soon as I'd heard that rattle, i'd have lost a day at work (£70), then had to spend a day or two stripping the engine and finding the fault (i've never actually stripped an engine so it'd be slow) or pay to take it to a garage. If they stripped the top end, i'd be looking at what, 3 hours labour? £120 at least? that's nearly £200 quid i've saved by running it, and seeing what happens or if it gets worse. Nothing did this time, so you can think of that saved cash going towards the time something really does go wrong.

speaking of which, the totally wrecked/blown up engines tend to be from blown rods etc punching through the casings, and as far as i'm away these don't give much warning at all, if any.

any way, what i'm trying to say is; if you've got a rattle (not a bottom end rumble at least) what are the main possibilities? 1) clearances out 2) loose cam chain 3) broken piston ring 4) primary chain shagged 5) gearbox shot.

I'm gonna guess that these are also in order of a) common-ness, and b) cost to fix.

so what are you going to do? strip the engine, split the cases, and measure everything, clearances and all? Even if you avoid the cost of a mechanic, you'll need the time and the tools, and the know how. that's why i'd say wait and see what happens, new symptoms appear etc.

you'd be amazed how often doctors just wait for symptoms, especially when the other option is to cut someone open.

[cargo]

I think the important phrase there is


"i've never actually stripped an engine"

[gavinfdavies]

ok, i've just re-read my original post, and i was being slightly t0ngue in cheek saying "see what blows up" and "see how it breaks". what i really meant was 'see what new symptoms show up'.

[cbrnoob]

Brought it to someone last friday!!! They told me my clutch bearing or releasing bearing is gone!!!! I didnt even know bikes had clutch release bearings
Anyone know were I can get this part as I can find anyting online?????

[Neosophist]

I have this on an engine.. when acellerating theres a definate clutch rattle, like a mechnical grinding noise at about 2000rpm.

Does it in neutral or in gear when riding. Will be stripping / replacing the clutch with a non k-batl type soon so will post back results of when i find out what was causing the rattle.

ps, its been like it 4000 miles, i put all weird clutch noises down to k-batl

[shjones]

I have exactly the same problem, Let me how you manage to sort it out.