So what is all involved in re jetting? I have a full race Vance and Hines exhaust that isn't selling on here so I am starting to get to the point were I might put it on. Does any bad drive ability come with this? What stage should I go to? How hard is it? Do i have to re jet? Just trying to figure out some answers.


Thanks

 

Don't buy the DynoJet kit, buy the Factory Pro kit.

The needles in the DynoJet kit are problematic, something to do with the design.

If you install any kind of aftermarket exhaust system you'll need to play with the jetting... Most kits come with recommendations.

 

Hersey did you get my pm as well for the tranny about the update?

Thanks for the tip on the jets.

 

Oh ya if I didn't do the jets it would run lean huh and probably blow up over time?

 

Yes, it would run lean (and hot) and over time you could burn up your valves and probably rings.

 

I have the "DJ needle" problem. They appear to get goobered up over time, if that's the problem people are talking about. I think they are made of some low grade of aluminum or maybe a an aluminum zinc composite. Either way, I spent about 5 billion hours buffing them back to a normal look with surgical precision, and it sucked. I'm praying to the fluid dynamics gods that I didn't alter their taper. I was real careful... I wish I knew a OE part number for a needle of similar geometry. I like where they're going with the vacuum slide mod you do for their kit and a lower spring constant on the vacuum slide return spring for snappier throttle response, and the jets themselves seem fine. My spark plugs looked pretty happy before I pulled the bike apart and started rebuilding it. The idea behind their kit is good, I think it's just the needle quality.

 

Also, I need to go for a quick soapbox sermon. Jetting isn't a mod. The idea of jetting "Stages" is confusing and seems to magically strip otherwise intelligent motorcycle owners of their common sense.

No kit is actually necessary with flow mods (i.e. intake/exhaust) You could just as easily meet or beat DJ and Factory Pro's kits by buying your own jets and carefully and thoughtfully experimenting to get your mixture right. You're paying for a little brass and a lot of research with these kits. It's fantastic to have something that plugs-and-plays, but don't get caught up in the idea that a "Stage I" is less awesome than a "Stage II." The only thing that's happening here is you're adjusting the fuel mixture to restore the optimal balance of reliability and power delivery that is lost when exhaust flow is increased. You want the "Stage" that the company specifies for the modifications your bike has.

In my words, you want the "Fuel-per-air" that the company specifies for your mods, they just don't call it that for some reason.

OkI'mdone.

 

never had any trouble outta dj....i clean my clean mine out regularly though.....
definitely like factory pro better though i "somewhat" agree with you hoffa i will say this ive experimented with alot of combination's and like where iam at and so does the dyno.......ive got a Frankenstein jet job though krux what are you looking for with power gains? what kinda riding you doing more or less?

 

I just installed a DJ stage 1 in my F3.

The plug & play option is extremely appealing. There are no local dynos I know of here in Philly. And to be 100% honest, I don't need power gains. I jetted my bike because I couldn't identify the Factory kit used in it and had all sorts of f/a problems (the primary being a malfunctioning air solenoid, causing the engine to asphyxiate).

I haven't run the bike hard enough to see problems with the DJ needles. And I probably won't ever. I'll gladly pay the costs of the little bit of brass that comes with the tons of research. And for restoring my bike to a known baseline.