125cc two stroke transmission issues after service
I’ve got a Fantic XE125 dirtbike which is basically a yz125 just remodelled by Fantic to be an enduro bike. It was recently in service, and now I have issues with the transmission.
About a week ago it was in service where it got a new front and rear sprocket, new chain, and also transmission oil change. I would usually change the oil myself however I didn’t have much time so I asked if the service could do it.
When I dropped off the bike I left them some transmission oil I had leftover, about 800ml was left. When I got the bike back I thought there was too much left in the bottle so I added in a bit more oil roughly 50ml. Then after riding for maybe 3-4 days I decided to check the overflow bolt which in the manual it says warm up the bike, then open the overflow bolt, if oil leaks there is enough, if it doesn’t leak, add more. It didn’t leak so I added the rest of the oil I had again roughly 50ml and still didn’t leak.
Then I took it for 1 more ride, and decided to drain the gearbox fully. There was 500ml when I let it drain into a measuring cup. There should be roughly 660ml in the gearbox so definitely low. I took off the front sprocket cover to check for leaks, however I dont see any obvious leaks. There is just quite a lot of black/rubbery grime but I think that’s just chain lube.
Then I decided to look online, and I am worried about an issue with the “crank seal” if I am understanding it correctly? I have definitely noticed a lot of smoke from the exhaust even for example after riding for 45mins, if I stop at a red light for 30 secs, and then go back on the throttle, there is a lot of smoke. I run 1:35 mix with e5/e10 fuel and Motul 800 oil. I always premix in a gas can and then pour that mixed fuel into the bike.
What would you suggest I do?