Thread: 100:1 Mix
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Old 12-23-2013, 01:31 PM
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Location: Central Texas
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Talking Re: 100:1 Mix

Originally Posted by rogergendron1 View Post
i have been doing a bit of research and found that yes...... a few racers do use 100:1 mix ! and i have also found photos of motors opened up after races that were run on 100:1 mix, it would seem that those who run 100:1 at the track do so for the minor but important preformance gain and the ones who run that mix at the track rebuild there motors after every single race. so it would seem they run 100:1 for the race and then rebuild the motor after the race and inspect every single part. this info was found on thumper talk and a few other dirt bike and atv forums, i even found a couple of people running 75:1 amsoil in 250r dune racer trikes on my old forum 3wheelerworld. but again it would seem that after the dunes they strip it down and inspect it and rebuild it.
so i stand corrected, 100:1 is used at the track but mostly in dirt bikes that are going to be rebuilt imidiatly after the race, i just have never seen it done in my life thats all.

the pics of the motors i seen all dirt bike engines looked pretty good and most all were slapped back together with the same parts needing nothing replaced excsept for the rings.

it would also seem that there are only a few oils run at 100:1 and they are amsoil, opti 2, and redline. the karting guys on some of the karting forums i was lurkin in thought 100:1 was insane and should never be done, they are all saying your a fool to go any richer than 40 to 50 to 1, but the dirt bike racers were 50/50 on it some said it offered a chance to open up wider possabilitys in jetting and provided more fuel into the chamber vs a leaner mix but agreed it was minor, the dirt bike guys had photos and everything and there are heated debates about it on the thumper talk forum, the small engine guys on the small engine repair forums all use it, no problems at all and they love it ! it would seem 100:1 is verry big in the landscaping industry and a lot of lawn care profesionals with expencive 2 stroke equipment use opti 2 and only opti 2 ! they swear by it !

so from what i have found so far motors around 25 to 100 cc reving up to 10,000 rpms can very well benifit from running opti 2 at 100 to 1. this would include our bike motors and even a lot of moped engines. but the larger dirt bike motors are not frequently run at that ratio unless they are tunned for a race and then raced at 100:1 and rebuilt right after. a lot of snow mobiels run 70 to 100 to 1 but those are newer snowmobiels that have special oil injection systems that spray oil directly on spacific engine componants, for instance the new rotoax motor usses oil at a ratio close to 150 to 1 !!!! but it would be unfair to include that type of engine because the oil is injected directly and not actually mixed with the gas, there for the oil can be injected in verry small amounts dircxtly on the componants that need it only when they need it.

finding a large motor that ran on an actuall mix gas of 100:1 was difficult but not impossable and it would seem that those motors are all race dirt bikes that rquire rebuilding right after the race.

however the uncanny amount of evedence i found in the small engine repair field and the landcaping industry and small engine forums would suggest that for a small motor ranging from 25 to 100cc and reving up to 10,000rpms will benifit from opti 2 at 100:1. even verry expencive custom built chain saws that are 70 and 80 cc reving to the max and are ussed in log cutting competitions are using 100:1 ! this is proof enough for me that it will work fine in our china girls even a high reving modded one, will i give it a try ? uuummmm yeh i guess.... i am still nervouse about it but i may start at 50:1 and move up 10pts every tank of gas till i am at 100:1, gradualy bringing my motor to the ratio, i am nervouse the sudden change in oil ratio and type might cause some type of damage so will gradually bring it there.

i would like to try it out... opti 2 that is ... starting at 50:1 and gradually brinning it to 100:1 and i will be putting it through the paces the whole time, reving it up and riding it hard like i always do, i want to put it to the test !
Sounds like a plan, no need for the ramping up to the 100:1 in my opinion because with a well tuned carb it isn't gonna matter because many of us have already proven that it will work just fine from the very first start of a new engine all the way up to several thousand mils with zero oil related failures, I say dont be concerned about reinvent ing the wheel here, we've already tested the water and its just fine to just jump on in and!

If your engine is in good mechanical condition, mix up some 100:1 fire that sucker up do a couple of plug chops to make sure you have the carb jet correct and ride the poop out of it and enjoy.

I dont always ride WOT, but when I do..I do my best to keep the rubber side down..Ride safely my friends!
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