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tommorth
7th September 2008, 16:35
im rebuilding my ktm engine and I got bearings for the gearbox from a bearing shop I noticed that they have grease in them should i remove it before I put them in? They will be lubed by the oil in the motor once fitted

FROSTY
7th September 2008, 17:05
Are ya sure you have the correct bearings?

tommorth
7th September 2008, 17:23
numbers on them match guy at bearing shop said most of there bearings come sealed both sides so remove seals if not wanted

Motu
7th September 2008, 17:36
I don't bother,but if you are the fussy type then do so.At gearbox temps the grease won't melt or mix with the trans oil....and shock horror,it could get on your clutch! In the real world it's not a problem and gives start up lubrication.

Ocean1
7th September 2008, 17:38
If the numbers match (including the second set, so maybe 6205 C3 for eg) then yes, use a scriber or similar to pick the seals out. Then wash the bearing in clean kerosine or diesel and fit it.

CookMySock
7th September 2008, 17:38
Make sure no grease gets in your engine/gearbox oil or you will pinch a bearing and run the bearing outer in its housing and wreck the casing.

Subike
7th September 2008, 17:45
seeomg as we are on the subject of bearings,
and we have some knowlagable people in here.
Those prepacked pre sealed bearings,
when replacing wheel bearings with these, when the old bearings had dust seals, is it needed to fit new dust seals?
Im asking in regaurds to front wheel bearings on older bikes
Opinions please, would help in discussion at work on bearins and their improvement of quality over the years.

As to the thread owners qustion, yeah, clean them very well and blow out with air gun.

tommorth
7th September 2008, 17:56
yeah the c3 bit (clearance?) matches the ones in the cases the only one which doesnt one of the genuine crank bearings

Ocean1
7th September 2008, 21:01
Those prepacked pre sealed bearings,
when replacing wheel bearings with these, when the old bearings had dust seals, is it needed to fit new dust seals?
Im asking in regaurds to front wheel bearings on older bikes

The quality of bearings hasn't changed much over the years, they've also been available with integral seals for a long time. What's changed in some cases is the application, drum brakes are a less friendly environment for bearings.

So, in such cases I usually leave the seals in the new bearings AND replace the original outer seal, but it does depend on the exact location and assembly details.

Ocean1
7th September 2008, 21:04
yeah the c3 bit (clearance?) matches the ones in the cases the only one which doesnt one of the genuine crank bearings

Yeah, C3 is the clearance. C2 is more common for slower speeds and cooler environments. There's more in that number set but 99% of the time you won't see them, not relevant.

honda929
8th September 2008, 18:48
Actually the quality of the steel used to make bearing has been improved.

vagrant
12th September 2008, 16:05
e.
Those prepacked pre sealed bearings,
when replacing wheel bearings with these, when the old bearings had dust seals, is it needed to fit new dust seals?
Im asking in regaurds to front wheel bearings on older bikes

As to the thread owners qustion, yeah, clean them very well and blow out with air gun.

I would be picking the seals out and repacking the bearings for wheel use.
The last couple of sets I have changed for mine and others bikes, the grease in the new bearing has been a very lightweight transparent gel. And not much of it either, just a drizzle over the bearing cage. :blink: Almost like an in transit preservative grease rather than an in use underload grease.

The front rim on my Fireblade has no space for the separate dust seal, but I am damm careful when I wash it of getting the hose anywhere near the hub.

Motu
12th September 2008, 18:13
the grease in the new bearing has been a very lightweight transparent gel. And not much of it either, just a drizzle over the bearing cage. :blink: Almost like an in transit preservative grease rather than an in use underload grease.


They know what they are doing,they make the things.

30 odd years ago we used to have bearing failure on pedestrian roller vibrating weight bearings - these were a large double row self aligning roller bearing,very expensive and a prick of a job to replace.So the bearing supplier was brought to explain why these things weren't up to the job.Their opinion was we were over packing the bearing - we were told to use a special grease,and the exact amount to use.It was a shitty looking grease,and only 1/4 filled the bearing,just a token amount.And we no longer had bearing failure.....