***?! Dyno Jet Needle No Good??

Ok so last month I jumped the gun and did "daves mod" without haveing the jet kit in... I then was called and told it was back ordered so I ran without changing the jet and needle until last night. Now here's my issue... I put the new jet in, .64 i Think it was... And the Dyno jet Needle went in no worries, I had to put the clip on the "third grove" any how... I do the work, put my back back together, and it sucked! My bike ran like shit. It idled fine, and was ok to about 2800 rpms then it was "starving" or flooding and just bogged. At first I thought I got dirt in a jet or something but that didn't make sense. the weird thing was it seemed intermitten.. Sometimes I had some kick ass power and then sometimes not. But then I had a FEW BACKFIRES, not pop's but BACKFIRES.. I went home took the Dyno jet needle out put my Stock needle and dave mod set up with the washer back in and now my bike runs WIKKED!!, Yes I did make sure my mixture screw was right. Now I did compare the needles, ans I noticed that the Dyno Needle was about a full centimeter longer...What have I done? is having the stock needle and dyno jet jet going to make any problems? I can use the dynojet needle but I would have to cut off some length at the fat end, (top) to make it work...

Does anyone else know what is going on? why that needle is long? or *** happened?

sorry I think I used 165... the one for stock exhaust.

I noticed the same thing.

Like the ignortant BRP rider I was, I ordered the Dynojet kit when I first bought the bike. In hindsight I never noticed performance gains.

From there, I embarked on a long and expensive journey on replacing parts in search of more power. Now I'm back to adjusting the carb. I recently replaced the dynojet main jet with a larger stock keihin jet and also replaced the stock pilot with a larger jet. The power was still down.

Oh a whim I compared the needles, and like you just noticed the size difference. I plan on reinstalling the stock needle and monitoring performance.

The needle only affects 1/4-3/4 throttle (don't quote me) wheras the main jet control fuel delivery at wide open throttle. So Ok to mix and match.

IMHO, I'd recommend returning the DJ kit and purchasing a few keihin jets and adjusting to what runs best on your bike.


Return the dyno jet stuff and do Daves modes using the stock needle and needle jet.

Honestly Running the Dynojet Main and the stock needle with Daves mod I noticed a significant difference. What size main jet then is the best one for some serious gain in power? It's too late for me to retur the kit so I am stuck with it. The one thing I was thinking of doing was cutting down the needle to "match" the length of the stock one. But would there be a point?

There would probably be no point.

The DJ needle is somewhat built to work with the DJ jet.


It's all about experimentation. Try the DJET needle with Daves mods. I did, and got very nice results with the stock carb when I still used it.

Play around with different needle positions and main jet sizes. It's a good way to get real familiar with your pig's inner workings.

Check the FAQs under jetting and follow daves mods to the T with the stock needle shimmed and the slide drilled and the stock spring and start with a 55/158 Keihin combo. There is also part numbers for the right jets under the FAQ. This is a good place to start and will be much better than the Djet kit. I had the DJet kit and it was nothing compared to Daves mods. You will find SMOOTH instant power.

I am pretty happy with the jet in now, but something is wrong with the needle set up... at 75mph it seems to be a little "flat" as far as acceleration... almost sounds like it's starving or something but I am still gaining speed... I think it's the needle set up... I am not in any way a crab guy. I barely understand them. I have a really basic knowledge, to me it's the component that airates a liquid to get the right amount of mixture for proper combustion. But how?..... A jet has a passage way for the liquid to be emulsifyed, depending on how much liquid can pass through is how much power you can get but too much liquid and not enough air then you run like crap, same goes if too much air, and not enough liquid.... But how is this all done inside the unit?

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