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Hi all,
I need some help with jetting and gearing, what do you all recomend for desert riding by way of gearing.
Also I have a JD jetting kit, twin air powerflow filter and bracket and the quickshot along with a pro circuit full system, getting a little popping on decel which says its running lean( all smog and airbox mods are completed) what jets are you guys using with this type of set up.
Thanks for any help you can give.
Mark

The jetting depends on the altitude you are mostly gonna be using the bike at. I am currently running the JD jetting using the 165 main jet. I am planning on stepping up to a 168-170 in the near future.

A good gearing combination I've found for the desert is a 14 tooth counter sprocket with a 48 or 49 tooth rear sprocket. This works well in the desert and keeps the RPMs down for the higher mileage ventures.

popping on decel

Just open your fuel screw an 8th at a time until it goes away. It probably won't take much at all to fix it.
Try that first before going bigger on the pilot,unless you've got a 42 instead of a 45,which almost all of us got stock. Doug

As for jetting if the bike is stock go with the mentioned 165/45 main/pilot combo.

As for gearing 95% of us desert people have changed our gearing to 13/49.

Don't forget that it is colder now and the air is denser. You may be OK with where you are on jetting after it warms up. Like was said above, just open the fuel screw a little and see. I am running the 170/48 combo at 600 to 7000 ft and it works on my machine, but since it got cold I do get a little decel popping.

Joe

What's the stock gears?

13/51

I am currently running 13/49 and I like it.

Dust Devil wrote:13/51

I am currently running 13/49 and I like it.

What's your top speed with that gearing?

About 90.

or should I say.."Very Blurry" I've held it WFO for extended periods and it just keeps pulling, I have never been able to hit the limiter.....but then again I dont go fast.

it cruses at around 65-70 without revving the hell out of the motor and still has great bottom end for the tecnical stuff....it's a godd compromise between stock and full on Baja gearing.

So going up on the front gives you more or less top end? Would just changing the front out do the same thing as changing the rear gear?

I for sure need more top speed. It seems like I'm always maxing it out in the dez. I don't like running it for a long time at high rev's.

For more top end go UP in front

OR

Down in back.

So will a 14 or 15 equal what you have? Has anyone gone 15 in front and kept the stock in the rear? I'm wondering if it would be to much for the bike at low speeds and RPM's.

JAWS wrote: at 600 to 7000

Thanks for narrowing down your altitude.....

I agree with DD, it's about 90 MPH with the 13/49. Running the stock 13/51 I hit 84 MPH on the dry lake bed. It wasn't against the rev limiter it just ran out of power (bike was stock) I hit the rev limiter after mods and the bike was screaming, so I'd say 90 MPH is a pretty good guess. Faster than you should be going through the desert for long periods of time.

Smash wrote:

JAWS wrote: at 600 to 7000

Thanks for narrowing down your altitude.....

I agree with DD, it's about 90 MPH with the 13/49. Running the stock 13/51 I hit 84 MPH on the dry lake bed. It wasn't against the rev limiter it just ran out of power (bike was stock) I hit the rev limiter after mods and the bike was screaming, so I'd say 90 MPH is a pretty good guess. Faster than you should be going through the desert for long periods of time.

And THAT is the definitive answer!!

Dust Devil wrote:13/51

I am currently running 13/49 and I like it.

Will the stock chain and chain length work with this combo? Is there enough adjustment left in the blocks?