Tonja, the story of a re/build bike

Project “Tonja”

This is the story about reviving, rebuilding, or better to say putting an M72 together from scratch ! I’d bought a frame of a 1961 M72, years ago, recently, 2019, I could swap it for a frame from a 1954 M72 That year I was born, I like the thought of having a bike as old as me. 🙂

’54 M72 frame

I’d had some parts lying around, leftovers from earlier projects, a refurbished spare engine, so it made sense to put it all together as an bike.

Earlier projects

Anoushka and Natasja
Anoushka and Natasja

Also bought a sidecar to go with it, I was able to get me an old type! I already had an M72 later type. Seems there was a version before this old type. See text underneath.

Old type sidecar
Sidecar “old type” M72

The second one is this one, the later type was the one with torsion bar.

“First sidecar frame doesn’t have a pipe over the mudguard so the axle is fixed only at one side.
It was probably too weak for russian conditions at war”.

info from Leszek,Oldtimergarage

The plan is to paint it in army colour and keep it as much as possible ” original” 🙂

1. the earliest form of something, from which copies may be made.
2. an eccentric or unusual thing.


Axle is stuck in some way

Improvised tool

With this “puller” and 5kg weight, I got it off.
Both threads are damaged, axle and inside thread sidecar frame.
Will be a challenge to repair this !

Painted frame

I welded some studs for an small toolbox and attached it.
Painted the frame with “Russian green matt military paint”, the front fork was in an other color, changed that now.

Brake plate isn’t complete, have to make a bush for it, to have the distance required and centered in the fork.

Because I use a Dnepr “glide” gearbox with reverse, that’s a bit longer than the M72 “crashbox”, I have to cut the original M72 drive axle and shorten it a bit !

final drive before the cut
Cutted final drive axle
Don’t forget to put the rubber cover and cap on the axle before you start welding !

The only thing I have to do now is weld it together Without the U-plate🙂

welded final drive axle
Shortened and welded final drive axle

cardan axle

I bought this regulator by this Dutch Electronica guy

finished regulator
Spiking and balancing the Wheel

I think I’ll have to find some real round rims, getting rather frustrated, no matter what you do you can’t get them 100%. They still a bit wobbly so at least for the front-wheel I would like to have a real round one !

The other final drives I have, have needles, this one is equipped with slide bearings.

Use a piece from a pet bottle when you install the seal else the splines will damage the seal !

Size, outside diam. 32, inside diam. 20, thick 21, 28 needles.

Complete plunger, in pieces. Extra spring on photo to show what happens when you try to get it off without tapping through a hole.

If there’s no hole in the ” bottom” cover, drill a hole, else you will ruin the spring !!
The spring goes off easily when you’re able to tap against it.
Trying to turn it off without the hole and a gentle tap will have the above result !

Damaged rear cogs
heating up a bit for less stress on the bearing
opened case
pull off the bearing
pulling off the synchronising gear
updated kickstart pedal with splines


now with MG holder