Pivot bearing conversion 856

[JPSeuropa]

Anyone ever convert one of these to real bearings. Those little cups came loose on mine and the frame is looking mighty chewed on. Reassembled with spacers which sort of work but things are damaged. I was thinking of converting to real bearings and wondered if anyone had had any success with a particular bearing. Seems like some combination of needle and thrust bearing would be the ticket.
Any suggestions before I begin my hunt?
Paul

[shovelon]

Yes, Simon of this group engineered a pivot replacement proceedure. He did this conversion on his 856 swingarm.

I had him do the conversion on my 957 and Oz, which are both carbon. Works like butter now.:-)

You might want to contact him to see if he would do it again. The key is his inline boring reamer that will clean the hole and open it to the size of the new ball bearings.

Terry

[Simon]

Like this



Simon

[JPSeuropa]

Simon,
Can you tell me what bearing you used?
Thanks,
Paul

[Simon]

Simon,
Can you tell me what bearing you used?
Thanks,
Paul

4 sealed precision bearings
24mm x 12mm x 6mm
619012RS



This is the basis of the conversion though things have changed a little,you cannot fit these bearings without first reaming out the pivots to suit.
Also not all 856's can be converted due to some having a missalingnment at the frame pivot mounting
drilling,if the hole through the frame is off centre then this system wont work.

Simon.

[JPSeuropa]

Thanks,
How is the life on those bearings?  ...I was concerned about using a ball bearing in a partial rotation situation although it does take care of the thrust load question. I shouldn't fuss really, those are very inexpensive @ $6 each.
My frame does have an offset hole, so that will require a bit of thought. I suppose I will have to see about have a larger hole bored on center.
My local machine shop will really hate this. They are still getting over the Miata steering rack I had them shorten for my Locost Seven build.
Paul

[Simon]

This system has been in use for a few years now,
my son,s 4500 and my 856 have never need the bearings replaced,
as far as I'm aware all those I've done for others, Oz's 957 etc have not had to replace there bearings,
you could also contact Will (Willem) he's converted his with smaller bearings that don't require the pivots to be reamed out.

Simon.

[mbrayf]

Hi guys, would this work for the 757 that i am updating... I am finding it hard to sorce the origonal bushings new so this would solve a small problem.

[shovelon]

I think it would work great.

Worth the investment if you intend to ride for a while.

[mbrayf]

Simon, if you read this, do you still make these and if so could i fit it to my 757 (i will require detailed instructions as im no engineer), or if your close to me.......    Mark

[Simon]

Simon, if you read this, do you still make these and if so could i fit it to my 757 (i will require detailed instructions as im no engineer), or if your close to me.......    Mark

I can email all engineering drawings some pic's and fitting and removal instructions,
unfortunatly I no longer have the facility to have the shafts made,
best I can offer is the s/arm pivot reaming to allow the bearings to fit.
Remember once you do this there is no going back.

Simon.

[JPSeuropa]

I guess I will drop off my frame and swing arm to the machine shop at the end of the month. I have a couple of weeks of travel that I wont be using the bike. Simon, could you email me the drawings. I have Solidworks and AutoCad. Anything else...please send IGES. That would save me a bit of time. epharhen@comcast.net

Thanks,
Paul

[JPSeuropa]

Got here done. Thanks Simon for the drawings. I had to make some mods to deal with some of the peculiarities and wear in my frame, but it came out great. Took an extra week as I had to deal with a cracked swingarm. It rides great. The combination of the Risse shock and the real bearings makes the bike rock solid. As I mentioned in a a previous post, I am good for another 13 kilomiles!
Paul Harhen