Rattling Engine - BMW R100GS

BMW R100GS 1990. Flooded the engine with water in Kyrgyzstan and stretched the cam chain. It sounded like a tractor for 10,000kms until we got to Japan and had it repaired. We rode 2-up across Kazakhstan, half of russia and around Mongolia with it sounding like this, and burning a litre of oil every 600kms.

Got it fixed then rode it all the way back to the UK!

What a bike!

Category:

Autos & Vehicles

Tags:

• bike
• motorbike
• BWM
• R100
• GS
• RTW
• Transasia
• sorebums

[greaserleo]

Hello, I've a bruised and battered r100s - it's making a rattle real simular to this, but only when the engine is hot and at certain revs. I thought it was the big end but wondering if its the timing chain. Did your bike make the same rattle when cold?

[simonthesculptor]

@greaserleo I agree with zoltar but exhaust all other possibilities before pulling down your engine as there are lots of things that can make it rattle. First thing I'd check is you carb setup, diaphrams etc. - have you a split diapragm? Have you had the valve clearanes checked? The timing chain and tensioners are worth a look before diving into the big-end - easier to at, and especially vulnerable to abuse in the later models = single run chain and not duplex chain

Simon

[castalian]

I´m just reading the whole story of yours in Chris Scott´s book, I suppose it is you :-)

Unbelievable!

[simonthesculptor]

@castalian Yes it is us and if you've read the Scott Book piece, you know that the bike kept taking more aabuse!

Simon

[dek139]

Vid is very clear, nice job.

I just got a 86 R65 it has some motor noise to it.

how did you know it was the timing chain? and how hard was it to replace. mine has 40K on it and was sitting about 10 years.

Thanks

[simonthesculptor]

I didn't know it was the chain until I had a mechanic strip the bike down looking for the cause.

[tomshiba51]

Amazing engineering. The BMW motorcycle engine design is 70+ years and still proving itself. It amazes me that they haven't decided to drop it altogether because of it's dependability. Lord knows that such a thing has happened with most industries today.

[505197]

@greaserleo ONe thing I've noticed is rocker arms can move laterally on the shaft, up and down in this case, in addition to pushing the valve inward. I use a C-clamp to tighten the rocker shaft mounts...hell I dan't think of what ya call them. You have to retorque the head when you so it. Hell I can fix um but I can't explain stuff very well, put the engine on tdc and see about sideways slop in the rocker, I think you will understand what I mean.

[zoltar5282]

@greaserleo The only way you will know if it is the big end is by getting in there. Since it is bruised and battered I would get in there anyway. Hot and at certain revs to me points to a timing chain. If you need any help, get on the airheads mailing list at micapeak.com. Loads of info and help there.

[alleywatson]

wow, what an engine