Sprag clutch repair

[Dellortoman]

Referring to Arnstein's info about the perpendicular base of the plunger holes - looking at my new ramp-ring I think I see what he means.
View attachment 55972
So that plug in the hole gets hammered off-perpendicular by the plunger which then destroys itself - and his modification is a longer plug that's braced by the ID of the outer ring, as seen in his excellent picture. Good idea and I'll do that one day but for now I just want to ride this bike once then see everything it needs.

You could achieve the same thing by making an outer plug that fills the remaining space in the hole and supports the inner plug, if you see what I mean.

If you have a lathe, it would be a simple job to make up a set of aluminium plugs, push them into the holes behind the existing plugs, then cut/file them so they're flush with the outside of the ring.

I suggest aluminium because it's easier to work with than steel. But plastic would work just as well if you can find a material that has a high enough temperature tolerance.

Come to think of it, epoxy will stand temperatures up to around 200C, so you could fill the voids with araldite. Stick a bit of masking tape over the hole to keep it in place while it sets, then move on to the next hole. But an even easier solution would be epoxy putty. Just shove it in the hole, scrape off the excess, and you're done.

 

[Arnstein]

JB-weld is even better and tolerates even higher temp., mix in some metal particles from filing and it will be harder. Or, use a cut off from an ordinary M7 bolt, I guess it is best glued and then filed flush with the ring.