New varator on- clutches so tight it stalls bike at stop signs!

George B. White /

Got new varator the other day and it is so tight - outer clutch to inner bell, that the rear tire will not move, if you try to roll it out of the garage, etc. It will start on stand, and will go, but you can tell it's laboring, the engine sounds almost as if its backfiring. The only way to move the bike is to lift the rear tire off ground to bring it outside to get it into position to start it. I thought if I rode it for awhile I could break in the clutches. After 10 minutes of riding I came to a stop and it immediately stalled. The clutch just will not spin inside the bell at idle- only stall. On trying to start it on the stand, as per usual - it would not start. That's when I tried to do my usual hard pedal start- and it was so difficult to do that I almost dumped it.

I'm really getting sick of getting parts that are defective. I think the internal sprung clutch shoes are too thick, i.e. the material is too thick on them, making it impossible to have them slip at idle.

Does anybody have a fix for this?

Yours,

Bluemill

Re: New varator on- clutches so tight it stalls bike at stop signs!

Dirty30 Dillon /

Potential for mis-install is always there, but where did you buy your "new" variator from?

There are many poo quality copies out there.

Re: New varator on- clutches so tight it stalls bike at stop signs!

Usually with reproduction parts you have to replace the entire unit and not just one piece. All of those new mbk parts on treats are Chinese clones so the quality can be hit or miss.

Re: New varator on- clutches so tight it stalls bike at stop signs!

George B. White /

Does anybody know the proper thickness of the centrifugal clutches, that's the thickness of the clutch/braking material on the shoes. It looks like 1/8" easily, but I'll take the main clutch off and measure with a digital micrometer. Do we have a tech on this site like DAVE of Dave Fixes his SHI*? He knows his stuff for sure on many makes too.

Re: New varator on- clutches so tight it stalls bike at stop signs!

You might wanna state your bike and post some picts, and what belt.

Re: New varator on- clutches so tight it stalls bike at stop signs!

George B. White /

The bike is a 1977 Motobecane 50V. The belt was bought last summer and worked fine for half a summer and fall, and a couple of good rides this spring. The belt is a Gates Power II - A30.

Re: New varator on- clutches so tight it stalls bike at stop signs!

So your talking about the leaf spring clutches on a moby, Deja vu on this subject. Sand where they are touching till the bell freespins.

Re: New varator on- clutches so tight it stalls bike at stop signs!

George B. White /

Thanks for the tip Jack! I sanded a long time on both swing clutches, and then determined tightness could be also the clutch outer edges too. I got it to the point where there was still some resistance, but the bike would start and stay going with the rear tire stationary. At that point, I figured normal material wear would smooth it out over time. Then took out for high speed run and it was real good- up to 25 mph hauling a hefty rider!

Re: New varator on- clutches so tight it stalls bike at stop signs!

George B. White /

This is to all who opt for the $70 varator from several parts dealers. The quality of materials is actually excellent, looking 100% like the original, except they use phillips screws, and they went overboard with the clutch material, especially on the ball operated centrifugal clutches. No need to take the thing apart to do the task, I sanded mine right on the bike. Just take your outer clutch off. I used small files and fingernail emery boards to smooth out the clutch material. Or, you could buy the OEM varator for $45 more if available.

Yours,

Bluemill

Re: New varator on- clutches so tight it stalls bike at stop signs!

You did grease the new variator right?

Re: New varator on- clutches so tight it stalls bike at stop signs!

George B. White /

Yes, I followed the service manual instructions, Also confirmed that the old grease inside the end of the crank shaft was not all waxed up - and it was very mobile.

Now I have a rich black spark plug issue. I'll likely take the carb off and look it over.

Re: New varator on- clutches so tight it stalls bike at stop signs!

Haha yeah on moby replacement clutches you gotta throw it on a lathe to cut the pads down.

I had to do it.

It’s not a great replacement.

Re: New varator on- clutches so tight it stalls bike at stop signs!

I would pick up a le partie ignition for your mbk

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