MA61 - 5 stud bearings used?

[ZZT231]

Hey All,

From reading Ed's Website http://www4.tpgi.com.au/users/loats/.../fronthub.html for the front hubs I should buy the MA61 front hub bearings as they are compatible with MS65 hubs. But if I am using MS123 rear end hubs, has anyone found a solution in finding the right bearing for replacment or do I get the ring made to be pressed onto the swing arm or something?

If anyone can shed some light in what bearings should I use for the back of the MA61 with the MS123 hubs?

Cheers.

[JustCallMeOrlando]

I was under the impression that the whole point was that the MS123 rear hubs were exactly the same as the MA61 ones, only 5-stud, and thus only required pressing on and off for 5-stud love.

[ed]

yah, what he said - thats the whole point of finding compatible axles... the bearings are the same as stock

[wilbo666]

Yep, just to say it again. Same bearings.

In fact atm I am 90% of the way through my 5 stud conversion

Cheers
Wilbo

[ZZT231]

The main problem with the use of the ms123 hubs on the ma61 lies in the fact that the ms123 hubs do not use the same bearings as the ma61. the internal machined diameter of the ms123 hub into which the bearings are pressed is significantly larger (~1mm) on the ms123 compared to the ma61, and the inner diameter of the stock ms123 bearings are also significantly larger than the ma61 owing to the larger crown spindle on which they run (see image below). specifications of the ms123 bearings are given below.

- Further on -

It should be obvious from the bearing specifications above, that the ms123 hub and bearing combo will not directly replace the ma61 hub. if you were to try and install the ms123 hub with ms123 bearings onto the ma61 spindle, it would immediately obvious that the ms123 spindle (from which the hubs were derived) was of considerably larger (~3mm) dimension than the ma61 model, and the ms123 hub would simply slop around on the ma61 spindle and never tighten. it soon becomes obvious (if not intuitively) that what's ideally required in this situation is a totally new bearing that satisfies the outer diameter requirements (eg 59,974mm) of the ms123 hub, and whose inner diameter corresponds to the spindle dimensions of the ma61 (eg 31,750mm). unfortunately, despite eyeballing 1000's of bearings, no such bearing specification exists (if you do find one, please contact me).

So I have a completely misunderstood what was on the website? So what you guys are saying is to get the MS123 bearings? as the outer race will fit into the swing arms? If so... Thanks...

[JustCallMeOrlando]

They're the same bearings as the MA61, that's the point

[ed]

So I have a completely misunderstood what was on the website? So what you guys are saying is to get the MS123 bearings? as the outer race will fit into the swing arms? If so... Thanks...

that discussion is about the FRONTS not the rears...

i never wrote a dedicated article for the rears

[Norbie]

Get MA61 or MS123 bearings, you'll find they're the same part number.