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View Full Version : '89 ZXR250 - engine noise slightly changed



Mikkel
6th December 2007, 20:39
This tuesday I went for an open training day at Ruapuna and absolutely caned my beautiful little bike. She ran really well and I thoroughly enjoyed myself.

I might have been a bit hard on her though - I hit the rev limiter on several occasions and hit a rather nasty false neutral shifting down from 5th at the end of the straight travelling 170 km/h.

Now she's been making a new noise since I took her home - she still pulls and runs as she used to, just a new sound.

It's like a whirring kind of sound that is present just around 8k RPM - and more pronounced when pulling than when just reving in neutral. Dunno if it is a combination of change of engine noise and some loose fitting somewhere hitting a resonance (that fitting would have had to have been shaken loose while at the track though).

Had a chat to my mechanic who seems to be a knowledgable chap and also has such a reputation. He said it wasn't anything to worry too much about - but I'm always a bit paranoid about such things.

Hope someone can offer some good insights!

Cheers
Mikkel

Edit: Typo in title - it's a 1989...

Pwalo
7th December 2007, 06:27
It's old enough to vote, so I wouldn't worry too much. Your mechanic is probably right.

Do you ride with ear plugs? If not try wearing some.

imdying
7th December 2007, 07:21
Just ignore it... if it's important, it'll let you know soon enough :yes:

Quasievil
7th December 2007, 09:09
Waterpump ? that would be my guess, that if it runs one, not sure



This tuesday I went for an open training day at Ruapuna and absolutely caned my beautiful little bike. She ran really well and I thoroughly enjoyed myself.

I might have been a bit hard on her though - I hit the rev limiter on several occasions and hit a rather nasty false neutral shifting down from 5th at the end of the straight travelling 170 km/h.

Now she's been making a new noise since I took her home - she still pulls and runs as she used to, just a new sound.

It's like a whirring kind of sound that is present just around 8k RPM - and more pronounced when pulling than when just reving in neutral. Dunno if it is a combination of change of engine noise and some loose fitting somewhere hitting a resonance (that fitting would have had to have been shaken loose while at the track though).

Had a chat to my mechanic who seems to be a knowledgable chap and also has such a reputation. He said it wasn't anything to worry too much about - but I'm always a bit paranoid about such things.

Hope someone can offer some good insights!

Cheers
Mikkel

Edit: Typo in title - it's a 1989...

Mikkel
7th December 2007, 15:50
Thanks for the replies... I ignored the noise and raped her some more today. 7 half hour sesssions of full out punishment and she took it in stride. I'll have a chat to my mechanic about the waterpump issue - he is fairly knowledgeable in the arts of ZXR250 maintenance, however noone knows all.

Mikkel
17th December 2007, 16:28
Since I last posted the rattle has grown worse and worse... The rattly part of the rev range seemed to be creeping further and further down the revs as well and it's rapidly gone from bad to worse these last days.

I had expected my mechanics to look at it today - but got the "sorry, too busy, see you after christmas" message.

So I went out to talk to Duane (who I've heard a lot of good stuff about). He was tied up as well and wouldn't touch anything until the 18th of January.

Anyway, I had him listen to the engine and he said, with great conviction, that it's the camchain tightener. Considering his experience and the certainty with which he replied I trust him to be right...
He also said I should not ride my bike unless absolutely necessary and if so I should keep the revs below 6,000 RPM.

So there you go. Mystery solved - now the challenge becomes to fix it. Preferably before the holidays.

surfer
17th December 2007, 16:49
if it is the cam chain it will only get worse if left and will eventually stuff up parts of your engine. Don't ride your bike meantime.

Good luck with adjusting it, not sure how to adjust it on your model of bike though.

jrandom
17th December 2007, 16:57
A ZXR250 workshop manual is available here (http://hosted.filefront.com/qldzxr250a/1471835).

If you can't find a workshop that will do the work for you, you might consider finding the necessary information in those documents and bribing a mechanically adept acquaintance to assist you in performing the necessary adjustments and/or part replacements.

It should be straightforward; nothing too scary about it. Just be meticulous and triple-check everything as you go.

It'll be a great buzz if you actually sort it out yourself.

:)

Mikkel
18th December 2007, 08:50
A ZXR250 workshop manual is available here (http://hosted.filefront.com/qldzxr250a/1471835).

If you can't find a workshop that will do the work for you, you might consider finding the necessary information in those documents and bribing a mechanically adept acquaintance to assist you in performing the necessary adjustments and/or part replacements.

It should be straightforward; nothing too scary about it. Just be meticulous and triple-check everything as you go.

It'll be a great buzz if you actually sort it out yourself.

:)

Cheers for the manual link... Have you got one for a ZXR-250A and ZXR-250B? ;)

And yes, I am tempted. I still neither have the proper tool nor facilities however.