E: Engine Main bearing outer race width

[bmetcalf]

You definitely want to read all you can to not make expensive mistakes. Vincent engines have critical differences from other brands.

 

[Phil Arundel]

Thanks Bruce - will do.
Sorry about the Manx Norton photo - I'll get the Vincent on when it is a bit further on!

 

[deejay499]

I always use a full width roller bearing on the driveside. My thoughts are the extra fit of a full track must be good. You will need a modified spacer ET19/1 as Bill states which is available from the VOC spares or you can take your current ET19 and if you have access to a lathe turn a step on the outside to allow for the extra width of the bearing outer track. this should be 1/8" off the width of ET19 to a diameter that just allows the bearing outer sit in. Do not remove 1/8" from the full face of ET19. You should see the difference in the attached screen shot for VOC spares.

You have to use a reduced width bearing on the timing side though.
Simon
View attachment 19398

:M

Thank you all for your replies. Some really useful information here.
I purchased my Rapide as several boxes of bits with new crankcases and 3/4" wide outer race main bearings.
Having not rebuilt a Vincent before I am finding the challenge very interesting and enjoyable (although a bit expensive!). This forum is so helpful!
By the way, I have sourced a pair of 5/8" main bearings from Conway Motors at £50 each plus vat. Conway have also proved to be very helpful especially with technical advice .
Regards
Phil

I always get my bearings from the local bearing company. Much cheaper. I just take the bearing or number down and if they haven’t got it, it is in in a day or two.

 

[Len Matthews]

:M

I always get my bearings from the local bearing company. Much cheaper. I just take the bearing or number down and if they haven’t got it, it is in in a day or two.

John, does your bearing stockist supply bearings with the proper brass(or is it bronze) roller cages? Some cheapies have pressed steel cages, are these up to the job?

 

[Len Matthews]

John, does your bearing stockist supply bearings with the proper brass(or is it bronze) roller cages? Some cheapies have pressed steel cages, are these up to the job?

Sorry, should have said Dave, not John.

 

[Bill Thomas]

:M

I always get my bearings from the local bearing company. Much cheaper. I just take the bearing or number down and if they haven’t got it, it is in in a day or two.

[QUOTE

:M

I always get my bearings from the local bearing company. Much cheaper. I just take the bearing or number down and if they haven’t got it, it is in in a day or two.

"Len Matthews, post: 90707, member: 178"]Sorry, should have said Dave, not John.[/QUOTE]

:M

I always get my bearings from the local bearing company. Much cheaper. I just take the bearing or number down and if they haven’t got it, it is in in a day or two.

Morning Dave, Do you have to get the outer track ground down after, Or do you do it yourself.
Cheers Bill.

 

[oexing]

Len,
I would not care about bronce cages, that is really old style. Better find yourself polyamide cages - if there are in imperial sizes. Modern roller bearings have higher load factors with PA66 cages , longer rollers and more of them .
I went completely metric with lipped races, home made crank too. Seems nobody ever made imperial roller bearings with rollers mounted in the outer race and plain inner races that slip right through all bearings as I found out when looking for roller bearings for the gearbox shafts.

Vic

 

[Len Matthews]

Len,
I would not care about bronce cages, that is really old style. Better find yourself polyamide cages - if there are in imperial sizes. Modern roller bearings have higher load factors with PA66 cages , longer rollers and more of them .
I went completely metric with lipped races, home made crank too. Seems nobody ever made imperial roller bearings with rollers mounted in the outer race and plain inner races that slip right through all bearings as I found out when looking for roller bearings for the gearbox shafts.

Vic

Concerning bearings with polyamide cages, I don't know if it's the same thing but when I worked for an MZ dealer I had to change quite a few plastic caged main bearings where the cages had broken up. It was suggested that this due,as a two-stroke ,the petrol mixture was causing the cages to fail.

 

[oexing]

What time was that, what brand and what type of polyamid was it ? I had these modern glass fibre PA66 roller bearings in other engines for long times and would not expect to have troubles with them . They are specified for 120 degrees long time and only some gearbox oils may be critical at high temps only. Bronce cages are no great idea in dynamic loads as they are very heavy, more so than steel cages. BMW had them in the sixties, some problems I heared, but that was not the modern type I suppose.

Vic

 

[Len Matthews]

What time was that, what brand and what type of polyamid was it ? I had these modern glass fibre PA66 roller bearings in other engines for long times and would not expect to have troubles with them . They are specified for 120 degrees long time and only some gearbox oils may be critical at high temps only. Bronce cages are no great idea in dynamic loads as they are very heavy, more so than steel cages. BMW had them in the sixties, some problems I heared, but that was not the modern type I suppose.

Vic

At the time the MZ was an East German product and in most respects a good machine there was always doubts about some components, namely chains(split rollers), tyres (the so called ditch finders) and bearings.Once these items had been replaced the bike would give good service.Problem was the buying public used to confuse the MZ with the CZ which was crude by comparison.