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Oil thread - sorta

Started by Dads_FJ, January 05, 2013, 11:55:32 AM

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Dads_FJ

Sticking this in Dirt Bike/Dual Sport section because it's a 2-stroke question. 

Question:  Assuming a bike is jetted properly, can a 2-stroke motor seize by mixing too much oil in the gas?  The question came up because my son who owns a 1972 Yamaha 200cc twin street bike (CS5) added mixed fuel, about 40:1, to the gas tank, but the bike already has an oil pump.  He doesn't usually run both mixed AND injected oil but it was all we had available.  My thought was worse case is a fouled plug, others say seizure can happen. 
Thanks for any input/thoughts!

(popcorn)

John S.

'84 Yamaha FJ1100
'89 Yamaha FJ1200
'94 Yamaha WR250
'80 BMW R100S/Sidecar
'39 BSA WM20

andyb

Too much oil means not enough fuel, and it'll go lean.

Buggered up an IT250 in the process of learning that.

bcguide

Yup more oil = less fuel = lean
Not to worry most bikes are jetted a bit rich
If you can find any of Kevin Camron's books on M/C  there is a lot of great info on tuning in them

Dads_FJ

Thanks everybody, appreciate the input.
John S.

'84 Yamaha FJ1100
'89 Yamaha FJ1200
'94 Yamaha WR250
'80 BMW R100S/Sidecar
'39 BSA WM20