C650GT Rear Wheel Bearing Life

[Norman]

This has been fascinating to read now, as the timing is perfect. I think I am in need of the same repair for the second time in 44k miles, last being done at the dealer. I am searching high and low for the needle bearing in the US, but seem to have no luck finding a bearing with the "ARS" designation. Do you know where I can purchase one? Also, I see these are sealed on two sides. I assume they are pre-lubed, correct? The other bearing seems readily available. Appreciate any information anyone has.

Thanks,
Patrick

40 x 68 x 15mm Sealed Ball Bearing (marked FAG 6008 2RSR). this is only one I replaced. The bearing place told me just to use a 6008 sealed bearing.
The needle bearing I just greased with plenty of high temp bearing grease. The seals looked ok but I shorted the spring inside. Learnt that 50 years ago.
A bit of a Backyarder Job...bike going good now ( 51000Km)

 

[ElwinNL]

I've been hearing a grinding noise in the back for about a week, and upon inspection the wheel has so much play that the brake is continuously grinding against the caliper - bearings completely shot.

I was able to source the ball and needle bearings, as well as the seals from the local dealer. Could anyone tell me the size of the socket I'll need to take off the not though? Is it a 48 or 50mm?

Also, good to read about the chain becoming stiff from the notchy ride and needing replacement - will do that too. I'm on 58000km / 39000mi, since I'll be replacing the chain, best to order a new stage 1 chain guide, right?

 

[ElwinNL]

I found the answer: the socket is 46mm

And I will be replacing the chain, not the sprockets, as the rear sprocket looks in great condition despite the chain feeling super stiff.

 

[Kiss4u]

Good evening,

A few months ago, you mentioned the torsion damper on the drive shaft.

There's very little chance of this becoming defective and causing the vibrations you're talking about. This is because the speed of rotation of the torsion damper is linked to engine speed, not vehicle speed.
What's more, the vibration damper is a simple mechanical part, not subject to wear. It is very difficult to break. It is not a consumable part in an engine.

A very simple way of checking that it doesn't cause abnormal vibrations is to remove the complete drive and belt (and therefore the clutch too), then start the engine. In this way, you can check that the drive shaft does not vibrate at different engine speeds. This is also a great help in understanding and identifying engine noises from transmission noises.

 

[Ceesie76]

Thanks Kiss4u, that makes perfect sense. Have not yet had the time to replace the rear wheel bearing but should be able to in the coming weeks and will report back.