420ae kick start freewheel

Hi all

I hope someone can help on how to replace the freewheel on the crank that's slipping on this bike on trying to kick over to start. I see from the diagram the brass inserts are recessed so it looks like they can't be pushed through on a press? So, how do you get the freewheel changed ? I've sourced a replacement here in the UK but I don't want to damage the brass either side of the freewheel, so I am asking the forums better knowledge!

Cheers

Craig

Craig,
Most of the time I use a blind bearing puller to remove the brass. If you are also replacing the brass then you can use a 1/4" punch placed on the inside edge and knock them out, but that usually damages the brass so only do that if you are also replacing the brass. Once you remove the brass insert from one side then the free wheel elements just fall out or pull out. Make sure you pay attention as to the direction/position the elements are installed in before removing them..

Marty

Cheers Marty, I'm on a learning curve !

Craig

.......slowly but surely !

What is the Ringspann part # for the freewheel bearing elements? Where did you purchase the brass inserts from?

Marty

cant you heat it like the bearings in the cases?

Marty,

Ringspann - article number 3620-012003-000000 Sprag set 12A15/25-49

Brass bushes were NOS Parts Now eBay store, they have one left. But now I have a set they are basic enough to get a spare set easily turned in a machine shop, so I’ll be looking into that.


The brass bushes were inserted but left no shoulder to pull using the bearing puller, so had to be knocked out. The puller marked the faces slipping. Heat was tried but not much success there. The sprag was taken through the brass and then the brass knocked out.

I need to get one turned so as I can fit these as I need one as a template for the machine shop !

Craig

Craig,
Thank you very much for the part number info. I wrote it down in my parts book for future use. I also have a NOS brass bushes on hand for a sample just in case I need to machine one out on the lathe. You probably have already checked but be sure your shaft is no worn on the crank were the freewheel rides on it.

Marty

Marty, yes I’ve still to check the internal size of the new brass bushes vs the external of the shaft for the freewheel....fingers crossed ! But Ringspann confirmed wear on the old set anyway.

.......new bearing internal, crank outside where bearing sits and crank outside where freewheel sits

Craig

Looks like your good on the crank measurement. I noticed the aluminum plug on the end has been counter suck. Make sure the oil feed tube on the clutch cover is long enough to feed oil into the crank end. That aluminum plug should be flush with the end of the crank. If the oil does not feed into the crank then the freewheel and possibly crank will be starved for oil.

Marty