Jetting

How does a guy know if he needs to buy a jet kit from JD? My bike starts good, no real hesitation or popping. Are the kits typically just to sort out the above problems or do they liven the thing up through the whole powerband. I noticed in one of the threads about the map switch that ville stated the switch makes a bigger difference if it's jetted correctly and i noticed absolutely nothing. I hope this question makes sense.

IMO, if your bike is working well, starting good, etc, no need to do anything more.

You can also refine carb's and do many advanced things to get the absolute best performance, but it has been my experience that messing with a good thing usually leads to frustration and a lighter wallet. :ride:

My bike starts first kick, but there are carb loyalists that always tell me there's more I can do. I'm pretty pleased where I'm at.

If it´s not broken then take it to pieces and find out why... :ride:

The kit does make your bike run stronger but if you really want to get the best out of it you also need to time the acc. pump,put more load to the squirt and either find a perfect sized leak jet or (much easier) get an adjustable acc. pump cover.

Nevertheless - If you´re satisfied with the way your bike runs & starts then there´s no need to mess with it.

the main reasons that people buy the kit are:

to richen the mixture and run cooler,... these bikes are jetted lean from the factory and JD's needle runs richer even though it's combined with a leaner main jet in the kit.

to imporve power delivery for your temps and altitude.

to improve starting

and with the o-ring/diahpragm mod you can pretty much eliminate the off idle bog that you will get when you snap the thottle open.... I'm suprised that you say your 08' doesn't do this as it does not come with a leak jet (stock)., .... unless you bought your bike used and the former owner did some adjusting, ....

lastly, ... as you encounter the odd misbehaviors from your carb,... James Dean backs up his product with good advice / customer support, ...

so I guess it's up to you if all that is worth $ 75.00 ?

If you do some forum searching you will find lots of threads on jetting and the kits effects on the 08' SX-F carb

Good Luck :ride:

you dont realize how much better it can run til you do it and get it right

the main reasons that people buy the kit are:

to richen the mixture and run cooler,... these bikes are jetted lean from the factory and JD's needle runs richer even though it's combined with a leaner main jet in the kit.

to imporve power delivery for your temps and altitude.

to improve starting

and with the o-ring/diahpragm mod you can pretty much eliminate the off idle bog that you will get when you snap the thottle open.... I'm suprised that you say your 08' doesn't do this as it does not come with a leak jet (stock)., .... unless you bought your bike used and the former owner did some adjusting, ....

lastly, ... as you encounter the odd misbehaviors from your carb,... James Dean backs up his product with good advice / customer support, ...

so I guess it's up to you if all that is worth $ 75.00 ?

If you do some forum searching you will find lots of threads on jetting and the kits effects on the 08' SX-F carb

Good Luck :ride:

Right !

Refines the delivery & fills in gaps thru circuit transitions you didn't know it had. The JD needles are finer thru those transitions & close the gaps. Kinda like a close ratio trans vs a wide ratio in the carb. Each circuit covers the other so its smooth, no jumps/lags, make sense?

Stock will do the job but the JD needles will get you that last few percent with testing/tune. Best $80 you can throw at a FCR bike.

I hope James comes with some sort of ... something for EFI bikes in a near future. His take on carburation is something every manufacturer should have bought a long time ago. All bikes should have been equipped with JD stuff stock. We have been ripped off over the years people.The man evidently knows more about fuel/air ratio and carburating than all high end engineers and researchers on any given factory.

I sincerely hope he has something up in his sleeve for EFI bikes as well. I´ve used his stuff on all of my bikes since -04 . I´ve also listened him and his advice and theories over the years and i dare anyone, EFI bike owner or not , to come and try my scoot and tell me that it doesn´t carburate as smooth,or smoother ,than any FI bike.

While a JD kit costs somewhat 75$ it´s a damn bargain. You don´t just pay for two needles, some brass,o-rings and membrane pins but you´ll get customer back-up that will put ANY customer service i´ve ever received anywhere to shame.

JD is THE man !:ride:

Thanks guys,

I'm gonna order a kit. Even if it doesn't get better power wise,(which i'm sure it will) I like the idea of it not being so lean and running cooler. It'll also give a little bit of a reason to start screwing around with the carb and actually learning how it all works, how to tune and the like. I'm also gonna get the power pump 2, I've read great things about it. Is the powerbowl considered overkill on these? I've read you can expect the same results from the pump cover/ALJ in the power pump 2. I also just installed a rekluse pro in it and i've heard that proper jetting really helps with the performance of it. The only problem is I wont be able to ride the bitch until the end of march. It's a balmy -30 C today, won't get to ride any time soon.

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