PM Disk question

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Fux
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Iv`e just fit a PM single disk (non anti-dive).

When I tighten the hub bolt the wheel will hardly turn. Back up the nut a quarter of a turn and the wheel spins freely but then I get some sideways play.

Anyone know what I am doing wrong?

Also in the instructions it says you can use washers that came with it to centralise the wheel. This bit doesn`t realy make sence because bracket for the caliper has to sit tight to the the (drum) link in order for it to sit correctly on the link stub.

The order of parts, facing the scooter are as follows.

Nut,link washer, link, caliper bracket, speedo drive, hub. on the othet side there is a seperate hub cone, and at the mo I have installed 4 washers.

As far as I can figure out nothing looks like its pressing on the outer bearing race so should realy run free when tightened.

I can also rock the speedo drive back and forth ever so slightly.
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wack 63
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I've fitted a few of these hubs and most needed small modifications to allow the wheel to spin free. It seems to be that when the bolt is tightened it locks the inner and outer tracks of the bearings up, to get around this I machine a small step on the cone to give clearance. The washers supplied are to centralise the hub between the forks. I'd much rather the hubs used a standard type axle as the bolt is a pain in the ass.
Last edited by wack 63 on Thu Jul 30, 2015 9:19 pm, edited 1 time in total.
Fux
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The cone fits fine on the inner ring of the bearing.

The speedo drive on the other hand is binding on the hub and bearing.

Image

I`m not quite sure how to solve this one. I fit the skinniest washer i could find behind the speedo drive but it means I have to shim the caliper. I`m in a bit of a hurry because I`m going to a rally in Denmark next week.

The speedo drive is 12mm thick so first off I`m going to see if i can find something I can make a spacer out of at work tomorrow as I dont need the speedo drive anyway.

As for centralising the wheel, Is it ok to fit washers between the link and caliper bracket? I was thinking that it was important for the caliper bracket to sit flush with the tab on the drum links?
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wack 63
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You can see where the speedo inner bush has grooved on the hub, machine that area down and leave a step to sit on the bearing inner race. As long as the caliper plate fits on the link lug you should be able to fit the washers to centralise the wheel.
Fux
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I`ll try that, thx
Fux
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Still shouldn`t come like this though...
Fux
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Turned down the outer edge 1.5mm and now its both tight and running free without any movement of the speedo drive.

I read on another forum (think it was the one over the pond) where a fella going through bearings like they were out of fashion. Could be something to look at.

As for the cone you mentioned, I think PM must have done mod on it as standard because the outer edge on it has already been turned down on mine.

I also wholeheartedly agree on the through bolt aksel. its a balls ache to centralise the wheel when that feker has to come out each time. :evil:
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wack 63
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Nice one, pleased you sorted it
Fux
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One step forward, two steps back...

After fitting the bugger I found that the supplied longer studs for SIP tubeless rims, also have taller heads and they were touching the caliper. I took the easy way out and used a polishing disk on the angle grinder and removed the two high spots of the caliper (had to do the same on my ScootRS caliper but for rim clearence)

Anyway all sorted, plumbed and blead. Modyfied the speedo sensor bracket so it could read the magnet I epoxied in one of the disk bolts, so I`ll ride the scoot to work tomorow to check how is works. It was easy to bleed at least.

Here is my setup for future refrence if anyone else decides to fit one..

Image

Image

Image
Last edited by Fux on Thu Jul 30, 2015 10:38 pm, edited 1 time in total.
shocky
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How much do you need to pack the hub to get it centralised ?
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