1978 KTM 125 MC5 overhaul

[joshn569]

I bought this bike a few years ago and it runs, but its got issues. Its in over all good shape for the year and its mostly complete.
The kick start shaft needs to be  replaced as well as the gears. It also needs crank seals. Gonna buy the entire engine seal/gasket kit. Its got a new oversized piston and bore job already.

I cant get the clutch apart... ant tips?  The bolts/nuts ( weird design) turn about a 1/4 turn then stop. Tried heat and I ended up breaking one off.  Havent split cases yet but when I do will there be anyway to hold the bolt from the back side?

The other big problem is the airbox and original carb is missing. cant find an airbox anywhere... any other years/model airbox that will work?

I dont have the money to "restore it" but an engine over haul with new seat cover and plastics should work.

[Gary Roach]

Hi Josh,

Welcome to POG!

About your clutch, turn the nuts until the slot in the nut aligns up with the hole drilled through the bolt. There should be a tiny cotter pin in it. The cotter pin kept the nut from backing off. The cotter pins are a pain to deal with, and instead of replacing them, you can just use a piece of wire and thread it through all 8 bolts, and then twist the ends together. To get to the head of the bolts, you'll need a very long allen wrench that can go in from the right side of the motor.

The '78 airbox was used one year only. I have a good used one, but it doesn't have a boot or filter. New filters are still available.

Gary