Motoscrubs.com

Hi guys.

I'm looking for the bearing behind the kickstart on the layshaft/output shaft - it's the only bearing I haven't changed in my cases and it's grumbling noisily.

I've searched two or three times times now on Google plus all the usual UK suppliers and keep coming up with a blank. There must be some stock somewhere - hopefully?

The bearing size is 30 x 52 x 12.

Any help or a link would be very welcome.

It is not a standard size bearing, at least it is not listed in my catalogue. I have a recollection of reading somewhere on here that Nigel had to get some made, but they are now sold out. Doom and gloom! Have you tried Road and Race Australia, or Ian Gowanloch at the Happy Farm? Possibly they may still have one left. What about Recambio Usado in Spain?

Why did Ducati use a non-standard bearing?

Colin

Hi Colin,

I've tried all the Ducati suppliers too - including Recambio, which was one of my first checks seeing as it's a Spanish Ducati - all to no avail I'm fed up with searching now as I've spent too many fruitless hours at it!

I may have to go down the route of fitting a bigger bearing and machining the cases to suit, the bearing I'm looking at is a SKF 6006 Open Deep Groove Ball Bearing 30x55x13mm https://simplybearings.co.uk/shop/p5154/SKF-6006-Open-Deep-Groove-Ball-Bearing-30x55x13mm/product_info.html

It would mean increasing the width of the housing by 3mm (1.5mm each side) and increasing the depth by 1mm, the flange behind the bearing is 4mm thick so I don't think the depth is an issue. I think the housing is just wide enough to be able to do this, but it will make me very conscious of not giving it the full beans in first gear

What do you think?

Bob
PM sent.

This is worrying for anyone with a Mototrans Ducati, if these bearings were specially made for Mototrans and are no longer available, then it will not be possible to keep these bikes on the road. Did Mototrans have a valid reason for changing to a non-standard bearing?

There are probably quite a few of these bearings knocking around in Spanish workshops, but finding them is another matter.

The bearing recess shown in Bob's photo measures 47x12 in my (Mototrans Elite) case and the bearing measures 25x47x12 which is an available size (phew) and is as stated in its parts list. There were many Mototrans models however.

Geordie must have an early Mototrans Elite that used the same bearings as the 125, with a 6005 bearing on the left hand side of the output shaft.
This is similar to some of the Italian 4-speed models ( the 160,200, 250 for example )
A series Italian Elites also use this bearing.
Mototrans later went over to the 52 x 30 x 12 bearing for all its 4-speed models, changing the output shaft first gear in the process, to give a larger area for the kickstart pawls to engage.
This is the bearing that is now almost impossible to get hold of.
I expect that with a bit of juggling it would be possible to fit some 4-speed Italian internals into a Mototrans case, although the left hand output shaft would probably need a sleeve to accommodate this.

Jon

There are several UK bearing companies who will manufacture small batches of a bearing, but God knows what the unit cost would be. There are 50 x 30 x 20(?) bearings available and I don't know if it would be possible to surface grind one down to the correct width?