Dyno jet kit has me wondering!!!

Is it for real or a mistake, does the dyno jet kit really only come with a selection of mains,a 160 and a 165? What about the pilot jet, shouldn't it be changed as well?

I've done the smog off(made my own plates,worked great) snorkel off,air filter ect. but found when i put the dyno jet kit in, it ran worse, so changed it back to stock and rode it like that last year. Now im about to put my new WB can and stainless header on, should I even bother with this dyno thing, or go with daves mods, or buy a different kit. I live and ride in the mtns of BC so elevation is up there, but heard that doesn't make much of a difference with four stokes, but I do know I need to re-jet after the exhaust mods for sure. I looked through the jetting forum, but got distracted so im posting, hoping for some info and direction.

Daves mod's are probably the best but the DJ kit in your case should work. Did you drillthe slide? If not you should per Daves inst. That in itself made a diff. You could all so just pick up a 55 pilot and go with the dDJ kit or put the stock needle back in shimmed. I used a combo of every thing and it was allways better than stock but the best way turned out to be Daves mod's. Then I bought a mikuni for it but thats another story.

the DynaJet kit uses that oddly shaped needle instead of another jet for the pilot circuit ... the only bad thing about the DynaJet kit is the price .... much cheaper to just go with Keihin jets, etc and follow Dave's mods ... the DJ kit in mine performs excellently, but if, for some reason I needed to replace it, I would definitely go with Keihin jets $$$ ... :thumbsup:

I didn't opt for the DJ kit because I wanted to have the ability to change jets depending upon altitude. We take the bikes all over the place so there's enough elevation change to "require" changing jets (4 strokes don't need much tinkering with altitude really). I read about so many issues with the DJ kit but I guess if you follow the instructions carefully it's ok. I agree (understand) the needle compensates for the pilot jet. It has a different taper. But again I like the idea of fine tuning which in my case required some swapping of jets when first setting up the bike. The DJ kit is more a one size fits all approach. Not necessarily a bad thing just different.

Nice!! Thanks Guys, the info is appreciated!! Since I have the kit, im gunna try it again, with the mix of Daves mods, drill for sure(I didn't yet!), maybe pick up a 55 pilot and use shimed stock needle. I know nothing of jetting for elevation, so ya think I should go with the 160, or the 165?? Or get a new/different carb!

Oh ya, i wasn't going to spend any more money on my L,haha right!!

I agree with roadcam - and in fact that is the answer that I got from dynojet when I inquired as to why the kit does not contain a pilot jet. They answered that the design of thier needle precludes the necessity of changing the pilot jet. The DJ kit albeit expensive - as compared to getting some Keihn jets - does work. The performance difference is not huge, the bike just runs better, idles easier while cold and warming up and maybe pulls a bit easier than stock, still emits a downhill off throttle puff-puff-puff as it is a big thumper, but gone is the annoying popping. Maybe it is just me, but I think the engine sounds like it is running with less effort than with the stock jetting. This was especially true for my XR250R when I replaced the main jet with a 135 keihn, removed the snorkel, installed a UNI air filter and a FMF aftermarket pipe. WOW!!! totally different motocycle - whack the gas and loft it in 2nd easy! the poor little 250 sounded sooooooooooooooooo inhibited stock like a stuffed up trail 90. So bottom line uncorking works. To the degree that you do it will give you the expectation you desire, a full uncorking on a 650L is undoubtedly wild! whereas with mine and a stock airbox (with Uni filter) and a DJ kit and smog removed and stock pipe runs well and strong. I just have not decided to swap out the exhaust yet, as I may use it some for commuting later this year and don't want an annoying loud drone on the freeway.

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