Oil Delete, what pre-mix ratio?
- Thread starter t30mg
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A
adam8781
Well-known member
32:1
run a good full synthetic mx oil (amsoil dominator is fantastic, maxima k2 would be my second choice)
its a big bore 800 that has to run minutes on end at over 8000rpm. these things thrive on oil. they make more power, run cooler, last longer. so dont skimp on oil.
My c12 only rm250 i raced for a while i had to run at 25:1 to keep any kind of residual oil in the bottom end. And sleds run harder longer wide open compared to mx bikes.
run a good full synthetic mx oil (amsoil dominator is fantastic, maxima k2 would be my second choice)
its a big bore 800 that has to run minutes on end at over 8000rpm. these things thrive on oil. they make more power, run cooler, last longer. so dont skimp on oil.
My c12 only rm250 i raced for a while i had to run at 25:1 to keep any kind of residual oil in the bottom end. And sleds run harder longer wide open compared to mx bikes.
T
tukernater
Well-known member
My buddy uses Same oil 40;1 Trygstad 872 No problems
A
adam8781
Well-known member
I'm sure it runs just fine.
But more is better (to a point)
how i was told to set up my 2 stroke mx bikes. run them hard, wide open cut the engine right where you get on and off the track (again, this is for bikes) throw my bike up on the stand right at the track. remove top end off engine, put a chopstick to the bottom of the crank case. there will be a residual amount of oil in the bottom end. My engine builder suggests i shoot for no less than 1/8th no more than 3/16 of an inch at 40:1 I had no oil, 32:1 about 1/16th ended up around 25:1 to get the builder required 1/8th of residual oil.
I have applied this to every 2 stroke bike i have ever owned with fantastic results. I measure my pistons, cylinder bores, piston ring gap etc.
I'm sure we could take three identical sleds. same premix but run one at 50:1 40:1 and 30:1. and all three will run great. take them apart at the end of a year with identical kms and the 30:1 sled would have much less wear.
But more is better (to a point)
how i was told to set up my 2 stroke mx bikes. run them hard, wide open cut the engine right where you get on and off the track (again, this is for bikes) throw my bike up on the stand right at the track. remove top end off engine, put a chopstick to the bottom of the crank case. there will be a residual amount of oil in the bottom end. My engine builder suggests i shoot for no less than 1/8th no more than 3/16 of an inch at 40:1 I had no oil, 32:1 about 1/16th ended up around 25:1 to get the builder required 1/8th of residual oil.
I have applied this to every 2 stroke bike i have ever owned with fantastic results. I measure my pistons, cylinder bores, piston ring gap etc.
I'm sure we could take three identical sleds. same premix but run one at 50:1 40:1 and 30:1. and all three will run great. take them apart at the end of a year with identical kms and the 30:1 sled would have much less wear.
T
teamthunderf**ked
Well-known member
I run 32-1 in mine and was told on a dyno that a guy started at 40-1 and kept adding oil all the way to 16-1 tell he started fouling plugs made horse power the whole way less resistance more power. i might bump mine up to 25-1 after hearing buddies story about his bike
Interesting! I remember reading awhile back about a similar test. I was thinking it was some where in the mid 20's but it's been awhile. Good stuff though. I too like 32:1 motor looks great after all tear downs. Have never burned one down running that ratio. I do rebuild my 860 every 1200 though. How often in the mountains are we to the bars? Alot! I would say more abuse in a day than a snowcross track. At least my day anyway
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