What’s broke ?

Brenden Duso

Member
Jan 13, 2018
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So my rn rm 125 was going pretty well until it stopped moving , it continued running so I assumed the chain fell off , I looked at chain and it was still on so i turned the bike off , I then went to push the bike while in gear and I just heard grinding and the motor didn’t turn over , I tried the Kickstarter and it does the same thing , the Kickstarter just grinds and doesn’t turn the motor over , if I push really really slow on the Kickstarter sometimes it turns the motor over but if I try to kick it it just grinds and nothing turns over ,could a broken kickstarer gear cause this ? If not what else
 
My bet is something with the clutch. Grinds when pushing it, grinds when trying to use kick start. Pull the clutch cover and have a peek.
So I have pulled it apart and it’s worse than I thought , the shaft that the primary drive gear sits on is stripped , I believe it’s the crankshaft but correct me if I’m wrong , anyway do I have to buy a complete bottom end kit to fix it ? Is there any posssible way to fix without tearing it completely apart and spending a fortune on a rebuild kit
 
You might be able to rethread it, either same size or next size smaller SAE thread. Pulling the crank would be the best way.
The small gear is on the crank, larger on the clutch basket.

You mentioned "rebuild kit" , describe what is in it.
 
You might be able to rethread it, either same size or next size smaller SAE thread. Pulling the crank would be the best way.
The small gear is on the crank, larger on the clutch basket.

You mentioned "rebuild kit" , describe what is in it.
Rebuild kit comes with crank , crank bearings, bottom end gaskets , clutch , all bottom end bearings and gears , but I don’t need all that and don’t have the money for it
 
Pics of damage might help.
Might be ghetto rigging but might consider TIG welding it on if you don't want to take it out.
What's the parts availability for this?
If it has center gasket you need that. If it doesn't rip, re-use it. Same with base gasket.
 
Pics of damage might help.
Might be ghetto rigging but might consider TIG welding it on if you don't want to take it out.
What's the parts availability for this?
If it has center gasket you need that. If it doesn't rip, re-use it. Same with base gasket.
I thought of a tig weld too , just not sure it would hold , and parts are very hard to find. And I already ordered gasket kit . Found a used crank on eBay for 100$ but it looks a little rough so I’m not sure it’s even usable