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08 250 jetting with Sunoco 110

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I am looking to dial in my jetting and was wondering if anyone was running a JD jet kit with race gas. Is the JD jet kit designed for pump gas or will the jetting be ok with race gas. I run straight 110 purple.

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it took alot of tinkering but id say i had it dialed in just about perfect very little spooge and kept the bike very, very strong throughout the range of the motor... my yz was 1000x easier to get dialed in than my kx, weather is changing quick here in ohio so i have the carbs apart right now trying to figure out what combo will work best for fall! since temp is about 20 degrees cooler then it was 3 weeks ago! you can get ur jetting just how you want it with these kits! i have one for every bike i own and will for everyone i own in the future!

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I had to go a step leaner on the main jet when i went from running 91 pump to a 50/50 mix of 91 and 110 sunoco

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yea i run straight 112 and ihad to go quite a bit leaner as well on the main but it wasnt hard to figure out and right now its almost perfect... havnt messed with it in the cold weather yet so im interested to see how easy it will b to dial it in when the weather gets colder... with the dryer air and everything. never rode much durring the winter but actually thinking of doin a little racing in the snow with my buddies this winter to try it out, but im not a fan of the cold so well see how things go! its also nice having all those jets avail. so when i go outta state to ride with my buddies i have em all and can keep my bike dialed in!

but the weather doesnt fluctuate as much in cali does it? you shouldnt have to change your jetting too often! correct?

had a buddy last year when we went to colorado that wouldnt even ride his bike because it ran so poorly and was pissed off n sat around in the trailer all week!

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Ya everyone seems to like the JD jet kits. I have always been a guy who buys all the brass and goes from there. Im still not sure what the difference is and why im so ready to drop $70 on JD.

I always thought race gas made the bike run leaner. :busted:

I suppose the Florida heat and the race gas might have me running rich too. Do you check this by looking for a nice tan / chocolate plug?

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Weather changes quite a bit from winter to summer but the humidity doesn't change at all.

All I have to do to prep my bike for each season is to swap the JD red needle for the blue or vice versa.

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it makes life so much easier to have everything you need right in front of you! and it also comes with some great advice in case your not very familiar with jetting these bikes and can go to the dealer and tell them exactly what you need!

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Having the squish on the head set will make jetting results so much easier. I run straight 110 leaded and it never really seemed to make much difference when I did a jet change. I cut my head to bring the squish to .050" and now the jetting changes are noticeable.

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Having the squish on the head set will make jetting results so much easier. I run straight 110 leaded and it never really seemed to make much difference when I did a jet change. I cut my head to bring the squish to .050" and now the jetting changes are noticeable.

My motor is at the dealer right now. Is this something a mechanic would know how to do? Is it easy for a mechanic?

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i dont trust the dealer... i dont let the dealer do any work on my bikes!

This "dealer" is a childhood friend. he knows his stuff. So the question is can he figure out the squish clearance?

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Dealers scare me most of the time. They are my last resort source of information, JUST information. They wouldn't get a chance to touch my bike :busted:

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where did i miss the point you said he knows his stuff and asked if you think he can figure it out, and i replied yes he should be able to figure it out if hes knowledgable like you say and you trust him with your motor! how is that missing the point?:busted:

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Is this something a mechanic would know how to do? Is it easy for a mechanic?

Do yourself a big favor. Send the head to RB Designs. Beautiful work, and quick turnaround times. www.rb-designs.com

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.

I always thought race gas made the bike run leaner. :busted:

Race gas ALWAYS runs fatter than pump gas. Temp and humidity do not change that fact. If your jetting is spot on with pump gas, you will need to compensate on the lean side for race gas. JD told us their settings are based on pump gas so you may need to make a few minor alterations when running straight 112. Just out of curiousity why run straight 110 or 112 on a stock motor? Save yourself the money and cut it 50/50 with pump. Will run just as well if not better. My YZ is jetted bullseye spot on and runs the very best at a 60% pump / 40% race ratio. 3 to 2.

Keep in mind, that in addition to running fatter than pump gas, race gas also burns hotter than pump gas. If like us, you choose your premix oil by flashpoint temps than you can also use this in your tuning.

Example: BelRay MC-1 has a much much lower flashpoint temp than Klotz R-50. Just little things to keep in mind while getting dialed in. This is why 2 strokes are so fun!

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Race gas ALWAYS runs fatter than pump gas.!

NOT true if using oxygenated race fuel. The blanket statement "race gas" is too broad of a term.

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