OI break in

[njbill]

I read the recommended 100:1 pre-mix in the first tank for break in. On Saturday, I'm riding my new Xtrainer for the first time and the dealer told me to disregard the pre-mix in the tank. He said that just generates excessive smoke. Any thoughts?

[wwguy]

I don't think your dealer is thinking this through very thoroughly. By Beta's own admission OI is all about lowering emissions, cost savings associated with consuming less oil, and rider convenience of not having to premix. It has nothing to do with increasing performance or longevity of the engine.

Engine break-in is basically a procedure to allow for the thermal expansion of the rings and cylinder wall to wear in the moving parts to themselves to obtain a good bore seal. This is critical to the performance and longevity of the engine.

So sufficient lubrication between piston rings and cylinder is obviously important during this high-friction break-in stage. Beta's OI system reportedly pumps a mere 1% (100:1) at idle and 3% (32:1) at wide open throttle. The additional 1% oil via premix during break-in gives you 2% total (50:1) at low RPM, which isn't excessive by any means.

Yes, you will be running 4% (25:1) at wide open throttle during the short break-in period, which might generate a bit of extra smoke without adjustments to jetting. But this is temporary and will have no ill effects on the bike. 2T engines wear out prematurely and/or seize because they don't have enough oil, not because they have too much.

FWIW I've disabled OI on my Xtrainer and run 40:1 premix all the time and my engine still runs like a top after 140 hours.

[njbill]

Thanks for your response.

[njbill]

Break-in complete with pre-mix added to the tank. It did smoke but, since I was leading the ride it was no big deal for me.

[aj_mariner]

I’m surprised that more people didn’t chime in on this controversial topic. How’d you like the ride?

[njbill]

I am excited to be back on a 2-stroke. We cannot get a tag for KTM 2-strokes anymore, so I've been riding 4-strokes for the past 10 years.