Mystery squeeking noise

[Redd]

My bike (10yr old Honda CA125, 4stroke, 2cylinder) has developed a rather worrying squeeking noise. With the engine just idling it's fine but as soon as you open the throttle past about 25% there's a constant squeeking noise coming from the engine.

As you rev the bike, the squeeking noise continues to change in line with the engine - higher revs - higher frequency squeeking.

It's not out of oil, it's not down on power (well, it never did pull particularly hard in 5th unless your going downhill), and I can't locate anything else that's causing the noise - it appears to be coming from the engine itself.

Any thoughts on a) what might be the problem, and b) how do I sort it out.

I keep expecting the boys on bigger bikes to piss themselves laughing at the noise coming out of it
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Professional Uberslacker
2006 Kawasaki Z1000 - Black at the front, airbrushed fade to red at the back.
1998 Kawasaki KDX 200 Enduro project bike

[Slinn84]

are you sure its the engine squeeking?

it could be the front sprocket, could be the brake pads on front or back, this would also go in line with the squeeking increasing as you accelerate

if your going along in 3rd gear and the squeeking is going up with engine speed, then you change into 4th, does the squeeking then drop down and start again?

if its something in the engine it will be very hard to locate

[Redd]

I'd pretty much discounted everything to do with the chain and sprockets because I can get it to squeek just by reving it while it's on the side stand and not moving.

I've looked and looked for anything else rubbing or emitting the noise but as far as I can tell (on my knees, revving the throttle with one hand with my ear right in amongst various parts of the bike) the noise is coming from the engine.

I should also have mentioned that when I said the frequency of the squeeking is pretty high, it's actually worryingly close to the engine speed

Yes, in 3rd gear changing up to 4th or down to 2nd the squeeking still follows the engine speed rather than the road speed.

This has an expensive feeling about it

____________________
Professional Uberslacker
2006 Kawasaki Z1000 - Black at the front, airbrushed fade to red at the back.
1998 Kawasaki KDX 200 Enduro project bike

[Slinn84]

hmmm
its a tricky one, just be glad it s a squeeking noise rather then a grinding noise

one thing u could do is try cleaning your carbs out, your carbs suck in enough air to equal the engine speed so if something is catching or contaminated then giving them a good clean out with some carb cleaner might work

honestly cant think of much else it could be

[Redd]

[BlackSheep]

Ratbike with real rats?

Sorry couldnt help it
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GSXR 1100 StreetFighter

[chriscross]

Camchain or tensioner?

TBH I know feck all about those engines, but if its something to do with moving parts in the engine then I thought it was worth a shot!

[BFG]

An old trick is to use a piece of wood to try and work out where in the engine the noise is coming from. Usually for rattles so not sure if it'll work for the squeak.

Works like a stethascope. Place one end against the engine and the other on your ear, move to different parts of the engine.

Maybe worth a shot.

Check Airbox for leaves, but I reckon air would make more of a whistle.

A squeak or squeal suggests metal on metal.

[DM]

Head gasket might be leaking...my friend's RXS made a squeaking noise after a rebuild which eventually disappeared, but it seemed to be coming from the top end.

[alfie698]

I've heard the sqeaking and it is weird. It actually sounds like a washing machine drive belt about to give up.
It's definitely coming from the engine, but nothing at tickover. I dont know anything about Honda 125 twins, but my first guess would be the camchain tensioner. Are they automatic? When should they be replaced?

Gordon, what is the mileage on the bike?

Cheers
Alfie
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[BFG]

[ZRX61]

Maybe the hamster fell off the wheel?

[Redd]

The noise is most definitly coming from the engine, and I reckon the top part of it. I refrained from looking a complete tit with the bit of wood, but it's definitly the top half of the engine.

The milage is in the region of 28000.

[theshmoo]

mouse
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CBR 1100 blackbird.