NS125F issues

[EnergyInducti...]

Still not running right, Replaced sparkplug, Recent engine rebuild...
Wont start on kick AT all...
It seems to start if you get a good run up on the bump start and then it smokes like mad with a loss of power.
No idle present whatsoever so if the bike drops below 2-2.5k revs, It backfires and dies.

I was thinking it was oil pump maybe letting in too much oil which is causing the extreme smoke (Compared to your average 2 stroke, Is this normal or due to cold starting?)...

EDIT:

No power in second gear, Only first.
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Riding: Yamaha RXS100
Aiming for : RD350 + Test
Dream bike: Suzi RG500 Gamma

[st3v3]

Seem's like some kind of piston failure, there's issue's.

Smoked could be where oil is getting through unburned cos there's no proper seal in barrel from rings? Both rings intact?
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Roger wrote: Women don't get damp for clingy puppies. Get some better happy pills, hit the gym & buy a medallion the size of a dinner plate. Job done

[Fortuna]

Couple of things I remember from when I had one.

Big black rubber intake block sometimes splits.
Reed valves go very quickly.
Oil pump is often mis-adjusted.
Small pickup coil can fail.

I also remember having endless problems with the carb, until it was rebuilt with new jets and new gasket.

When you say the engine was rebuilt, can you say why and more importantly how? Reason I ask is they have a nickasil barrel.

[st3v3]

[stevo as b4]

No idle, and reluctance to start, accompanied with smoke and a loss of power all suggest low compression TBH! Do a compression test before you strip it down to confirm this however.

[adam coomber]

sounds like piston rings arnt working right cause that is what happened to mine the last time round and the rings had stuck in piston causing compresion leek.....