Is pre mixing oil with fuel required on new 70cc?

[poinndexxter79]

I thought the Malossi 70 ECU was supposed to regulate the amount of fuel for the new engine. My engine is blown now after 60+ miles on it and I was very careful with the throttle, only 1/4 -2/3 throttle. This is a very expensive lesson, do I need to pre-mix 2T oil in my fuel when running a new top and bottom end?

[NoNameForEver]

No, that would not help a Ditech engine..

[NoNameForEver]

Did you remove the oil line from the mikuni oil pump during this rebuild? And if so did you prime it/bleed the oil line? High-Gain oil line bleed procedure..

[poinndexxter79]

Did you remove the oil line from the mikuni oil pump during this rebuild? And if so did you prime it/bleed the oil line? High-Gain oil line bleed procedure..

No, the oil line was nor removed at any time.

[NoNameForEver]

The psi number sounds fine to me, but I'm not sure since this is an air cooled cylinder. Did you grease the crank bearings during rebuild? Have you checked the crankshaft on the front variator for any play/movement up/down left/right?

[poinndexxter79]

The psi number sounds fine to me, but I'm not sure since this is an air cooled cylinder. Did you grease the crank bearings during rebuild? Have you checked the crankshaft on the front variator for any play/movement up/down left/right?

Yes, I checked the front crank shaft today while doing my TPS reset. The crank bearings were greased very well. Maybe my compressor? After I had it drilled and tapped to 1/8 , I used brake parts cleaner to spray out the small metal shavings but I did not re lube it. I thought it would re lube itself with 2T oil. Is that what is gone wrong? My compressor cover?

[Snugg]

Do make an accurate diagnostic, it needs to be taken apart and the failed part needs to be located. Once you know where the problem is, we will know what caused it.

I thought you only installed the BBK, you did the "bottom end" as well meaning crank, bearings and seals? How did you check the "front crank shaft"? How is it that the bottom end was replaced without removing the hose to the oil pump?

[NoNameForEver]

The air compressor could explain it. Time to pull it and inspect.. Have a look in in this thread. Read from page linked to and the next ones..

[Snugg]

I'm a little confused.
Did the scooter just stop running? An air compressor can cause damage if it somehow broke and something dropped into the engine case and got picked up by the crank. Other than that, a failed air compressor won't cause a "blown engine". It would just not run. Unless I'm wrong, somebody correct me

I'll wait to comment more until after you find out what part failed.

[NoNameForEver]

Other than that, a failed air compressor won't cause a "blown engine". It would just not run. Unless I'm wrong, somebody correct me

You, wrong, never.. A failed compressor, makes the scooter a non runner... fast. If so, it's a little bit ouch..

[NoNameForEver]

No, the oil line was nor removed at any time.

So when you split the case removing the old and installing the new crank, bearings and oil seals, you did not remove the oil line from the Mikuni solenoid? #8

[Snugg]

You, wrong, never.. A failed compressor, makes the scooter a non runner... fast. If so, it's a little bit ouch..

Yes That's exactly what I said

[High-Gain SR50]

Yes, I checked the front crank shaft today while doing my TPS reset. The crank bearings were greased very well. Maybe my compressor? After I had it drilled and tapped to 1/8 , I used brake parts cleaner to spray out the small metal shavings but I did not re lube it. I thought it would re lube itself with 2T oil. Is that what is gone wrong? My compressor cover?

My guess after hearing that is some debris is stuck under the compressor disc.

[poinndexxter79]

So when you split the case removing the old and installing the new crank, bearings and oil seals, you did not remove the oil line from the Mikuni solenoid? #8

I was not there when my mechanic split the case and installed the new malossi crank, I trust that my mechanic did it correctly, I hope. The bike shut down today and when it did, it felt the same as when my water trap line popped off. The bike just lost power , it started up again 10 seconds later only to idle very low and just shut down again. Compressor?

[NoNameForEver]

Yup, post #8