Hello ossa people,

I have recently had my 125cc TRI 2013 engine all rebuild because the crankcase was all split open at the air-inlet side below the cilinder.

Now I got it back with a new crankshaft in a new case.

When testriding I noticed I didn't have power and I can not get the frontwheel of the ground like normaly. 

I was told by the store that it takes at least 10hours to losen up the new crankshaft so that my horspowers will return to normal. 

When opening the throttle I notice how the RPM's are slower comming up.

Indeed it feels that the engine is so tight that the piston is not running lightly.

Mecanicaly the gears and clutch seem to work fine and also the injection seems ok.

Anybody familiar with this aspect on the Ossa TRI ??

Long shot my 300 Ossa needed a bit taken off the inside of the flywheel as it touched the crankcase after it had mains, I don't know what caused this, worth checking. All a bit odd! 

Edited November 21, 20214 yr by Stomp

On 11/21/2021 at 6:39 PM, Stomp said:

Long shot my 300 Ossa needed a bit taken off the inside of the flywheel as it touched the crankcase after it had mains, I don't know what caused this, worth checking. All a bit odd! 

Thanks Stop, I'll try to find out if this may be the case.

the dealer telling you that it takes 10hrs to run in a crankshaft is garbage.

it should have been rebuilt with assembly lube. i would be taking it back and getting them to check all crank bearings etc.

Be sure the pin-locked crank bearing was fixed correctly (pin screw to the bearing's groove). If the pin doesn't hold it, once the engine heats up and metal expands the crank can drift w/o mechanical lock with pin - thus with a "drifting" crankshaft some of the crank sides (magneto or other side) can contact the crankcase at the extremes.

Edited November 23, 20214 yr by tsiklonaut

Today I spoke with the dealer and he explained me like this:

He put a 2015 model crankshaft, bearings and parts instead of the 2013 model.

This should be so much better quality that this engine it will keep running good for much longer time.

Beacuse these parts are a very tight fit, a 125cc will show much less power while breaking in.

He convinced me to continue breaking in and gave me lifelong guarantee on the repair.

He is not that old so I guess I can trust things will work out one way or the other.

Lets's hope for the best.

I will get back at this topic in februari/march when I am back in holland. Then I'll be completing the 10hour brake-in.