Stage 1 dyno Jet Kit (jet sizes)

My XRs only header and muffler just arrived, as well as a dynojet stage 1 kit. Does any one know what size jets (pilot / main) comes in the kit? (05, XR650L)

Any help would be appriciated!

It comes with no pilot jet, and 2 jets that are sized differently than keihin jets. (unless they've finally updated the darn kit...)

Aftermarket exhaust, you'll want to use the larger jet (I think they call it a 65).

You will want to put in a larger pilot jet. 55 or maybe 58.


Personally I decided to stear clear of the dyno kit because of forum comments. You could go ahead an just by the larger jets. For 3800 feet elevation I use a 55 pilot 158 main with Uni air filter and White Bros. series E with 6 discs installed.

Those above jet numbers are Keihin numbers and I think I got them at Sunco.

The only other bit of information I've heard about the kit is that the needle they supply has a different tapper than a shimmed stock needle(thans why the jets are provided as they are in the kit). So the result is that the needle is relied on more, to supply various amounts of fuel, rather than jets. In the end the power band is not as even or smooth vs. swapping jets. I don't know if that makes any sense to you but I guess the kit is ok not great.

If you decide you don't like the kit results, which I have heard from some, go to swapping the jets, shim the stock needle .025", drill the slide holes and use the stock spring.........that's what I did and it's runs super.

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