Gearbox from Runner 180 (disc) into 125 (drum)

Heya!

I have been wondering if I can fit gearbox from 180cc Runner into my 125cc Aprilia SR. But I have been wondering if there is difference in final shaft length/shape. I have drum brake, but 180cc usually have disc brakes. Are they replaceable without press?

 

Rolling or non rolling clutch nut?

 

Damn, You got me there, I dunno, how Can I check it?
EDIT: Does it make a difference?
EDIT: What difference it makes?

 

You need to know engine type they are, yes there is a difference.

 

Ok. I found information here: https://www.scootershack.co.uk/threads/rolling-nut-engine-dafuq-does-it-mean.32503/#post-306070
And I guess You mean If I have this cover
Or this:


I have this second one.

Can You deduce from that if I have splined or forced gears or what?

 

You have the early "non rolling nut " engine, the gears from the top picture won't fit. You could get a complete 180 non rolling gear box and fit it straight in!

 

Ok, I just ordered whole gearbox from 180cc. Soon, I will know if it fits. It only costed me 20GBP with shipping, no worries.

Also, could You tell me if that engine has a name or codename? I noticed that in parts catalogue it is named M121M or M131 (http://www.apriliagenuineparts.co.uk/component-special-tools-h-piaggio-engine-3820.php).

 

i belive all transmissions can be fitted in each engine case, i experimented with diffrent gears from skipper hexagon and runners.
as long as u dont have a dubbel roled engine cover you can switch al the gears.

 

a primair set of gears need to stay together aswel as a secondair gear set. but you notice it easly when you try to fit 2 wrongs gears.

 

well sorry for my last mesasge, i found out the hard way that you cant put a dubbel rollend primairy shaft and crankcase cover on a single rolled engine... bought the parts for nothing

 

You'll have to sell me the gearbox that doesn't work !