WTB motobecane main shaft bearings

I've posted this ad a couple of times...does anyone carry these this side of the Atlantic?

Re: WTB motobecane main shaft bearings

Jason Luther /

are you looking for a cady bearing?

Re: WTB motobecane main shaft bearings

No, I need a set for my 40t. Every local bearing supply shop I've checked insists that the sizing is just not available. They all suggest going to the manufacturer. (last time I checked, I think Motobecane is out of business). The only other option is RVC Team - in France....Hey, I'm just throwing this one out there (again) hoping that there is a cache of Moby bearings somewhere on the North American Continent.

Unfortunately, this problem seems to be the kiss of death for these engines....any comments or solutions?

Re: WTB motobecane main shaft bearings

Why not just get another bottom end? With a variator while you are at it? You can probably find a whole engine for under $50.

Re: WTB motobecane main shaft bearings

That seems like the best solution, by far. I definately want to pick up a variator anyway. However, I do have a complete set of gaskets and seals and I'd like to do a bottom end rebuild of my own. If necessary, I'll navigate through the RVC-Team site and get the bearings. (But, if you are selling a decent bottom end with variator for $50, I'm interested in that too!)

Re: WTB motobecane main shaft bearings

Has anyone actually got new bearings from RVC and installed them?

Re: WTB motobecane main shaft bearings

I did receive new bearings from them for my 50V but I have not installed them yet. That's a winter project for me when I can take it down in to my shop and work on it when it's cold outside.

Re: WTB motobecane main shaft bearings

I don't know from first hand experience but I've heard that their bearings don't come with the proper radius on the inside taper? I hope I heard wrong. It is very strange that these bearings aren't available locally or at least stateside. Millions of MBKs were sold and it seems like they are always the ones that need main bearings.

Re: WTB motobecane main shaft bearings

I hope you heard wrong too! If they don't work, then I have a beautiful 50V tht will be put on the shelf as "art."

Re: WTB motobecane main shaft bearings

If they don't work I might be able to come up with a pair for you. I had my brother machine a set for me, it is possible to grind the id of a 6203 bearing to spec but it takes so long it is not cost effective VS importing them.

Re: WTB motobecane main shaft bearings

I know Chris at the Mopedwarehouse has also made some up before. He has an unreal machine shop and more tools than any mechanic I have ever seen. Both him and his brother are very resourceful at getting the job done.

Re: WTB motobecane main shaft bearings

I was thinking that it would be possible to insert a metal sleave/collar on the crank shaft at the 16mm point. I'd start by drilling out the ID of the collar to just under 16mm, heat it up to maximum expansion and pound it in place. Then I'd machine down the OD of the collar to 20mm where it would match up with the ID of a more common bearing. (I can easily obtain a bearing with an ID of 20mm and the correct OD to match the cases). Do you think that would work?

Re: WTB motobecane main shaft bearings

The collor you'd machine would have to have the proper taper and radius on the inside edge to fit properly on the crankshaft, otherwise it sounds like a workable idea. I found a place where I could get the 16mm id bearings but I would have to get 3000 of them minimum, then they would still need machining.No easy fix for this problem it seems.

Re: WTB motobecane main shaft bearings

I have a set of reinforced bearings from rcv-team installed on a doppler crank and ready to go into a reed valve bottom end. I tapped them on using a section of sawn off handle bar. They nestled in perfectly and feel really great.

Re: WTB motobecane main shaft bearings

Bret, is the doppler crank the same dimentions as a stock moby crank? Does it measure 16mm where the bearing seats?

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