Honda Bali Sj 100cc Over oiling problem

[milly]

My knowledge of 2 strokes is very scant these days last ones I had was BSA Bantams way back in the 70's.
Month or so ago had weak spark and bike packed in. I had 2 spare new plug's with me but still weak.
Fast forward to yesterday had time to work on it. Changed CDI unit for a new one and coil also noticed throttle cable had got quite stiff from standing.Renewed that today and lined up cable and oil pump marks as per official Honda manual. Bit hard to start so checked petrol flow to new carb as fitted a new vacuum pump and carb 3 months back all good. All hoses good also.
Bike will start and working at low revs but not high.
Took out and changed around the plugs but they both come out oily.
Could the crankcase oil seals have anything to do with this?
Or cable being stiff and partially leaving oil pump open let it seep by over a period of time?
Did spray carb and hoses but no revving due to leakage.
One job I have not done yet is check carb see if blocked.
Not compression test or check if crankcase is full of oil.
Any pointers anyone?

[190mech]

There is a check valve (usually in the carb discharge port) to keep oil from gravity feeding when not running..If it's not sealing the case will get loaded with oil..causing fouled plugs..

[snaker]

2 strokes really can be witch craft.
The part that stuck with me was your symptom of starting and running at low rpm's but not high rpm's.
Obviously a plugged carb can do this.

Crank case seals can cause it as well.
I think that different brands can be more or less prone.
For example, I experienced Rotax singles having that very symptom with bad crank seals

[milly]

Thank you 190mech and snaker. I shall check when get chance in the next fortnight.

[jackrides]

Check for water in float bowl.

[milly]

Today I have not had much chance other than to spin engine over with plug out to see if any excess oil appeared with a tissue by the plug hole but there was none. 
Did a compression test that's a 100psi

 Fired it up after but forgot to take plug out to see the state of it. 
Anyhow there's a video of it at tickover and after about ⅓ throttle starts going worse right up to full throttle.so maybe main jet?
I also had 4 stroking as well but not sure if on video

[milly]

Been busy of late plug was oily as stated and after putting tissue over plug hole no oil come out onto it so crankcase not full of.
Next check new carb which was the most likely culprit in the first place. Being new doesn't exempt it from blocking up with debris in the fuel.
Get on the case this weekend hopefully as granddaughter wants her ride out being school holidays.

[jackrides]

Check valve and hose may only need disassembly and cleaning. But, (the one time I dislike goats) the spring may be shot. Quick test is to stretch it with your delicate fingers a Little bit and see what happens. I rad there is a pressure test for themfor the techies.