question for those running dr.d pipes

i have a 03 450 with dr.d full system. put needle to 3rd clip postion, msr air/fuel screw nothing but problems cant get bike to run the same as it did before installing msr screw, my question is how many turns out on stock screw for sea level riding,thanks

1.5 turns out should get you close enough to get started. Are you sure you have the correct screw? There are several differnt models of screws available depending on which carb you have. Hold it next to the stock screw and look carefully at the pointy end; that part should be identical.

1.5 turns out should get you close enough to get started. Are you sure you have the correct screw? There are several differnt models of screws available depending on which carb you have. Hold it next to the stock screw and look carefully at the pointy end; that part should be identical.
ordered 2 one for my 02 426 and my 03 450, both bikes nothing but problems with the msr screws, i got the red ones i know they also have black ones, but you say i should try going back to the stock setting for the stock screw at 1.5 turns out. never been good with carbs, are you supposed to find the highest idle after that , i cant remember.

There are manufacturers of fuel screws that do work, ZipTy makes a good one. And Yes.

I agree about the Zip-Ty, it works very well when conditions change (i.e. temperature, altitude, humidity)

1.5 or 2 turns away from seated should work.

One thing IMPORTANT!!

When you screw the fuel screw in, don't really crank it down tight, just use enough pressure for the fuel screw to lightly reach it's furthest in setting.

If you crank it in really tight, you will deform the tip and cause problems with trying to get the bike to run correctly.

I have a DR. D slip on, wish I could help but I am in Idaho where the altitude is 3,000ft to 8,000ft. However, when I installed my pipe it ran fine and did not need any jet changes. Keep trying and do not give up on the DR. D system because it will be awesome when you get it to perform. My system improved throttle responce and made the power feel broader between gears.

my 03 450 came with a drd on it. I personally like the WB pipes better.

But stock jetting it ran great with just tuning the air screw. But it was not jetted properly by any means. I installed the JD jet kit with the red needle and it instantly woke the bike up!

Tips:

If you are more than 2.5 turns out, you need to go richer on the pilot. If you are under 1.5 turns you need to go leaner on the pilot.

Be sure you remove the Leak Jet from the bottom of the bowl and blow through the passages. If that gets pluged, the AP will not work correctly. Also remove the AP diagphram and clean it. make sure it is still pliable and not torn. Then time the AP squirt on the carb.

Run the stock pilot and 180 main to start with and go from there on the jetting. Oh, it should not have to be said but clean the air filter before trying to jet the bike

First take the screw out and make sure you put the parts in the right order. Spring, washer, O-ring on top..... I think :ride: Check me fella's.......If you don't have a manual go on line to the Yami site and it will show the order of the parts.

Call DRD I'm sure they can help. :applause:

i thank you guys for your help, i called dr.d they said to go out 2 turns and start from there, but what am i looking for? dont know if i am running to rich or not, all i know is that backfiring is no good and right now it does it a little on deselleration

before you attempt to jet you need to understand jetting and where you are having the problem.

Backfiring, when? what gear and how much throttle do you have applied?

Popping on deceleration, that can be jetting or an exhaust leak.

I would suggest that you mark your throttle in 1/4 increments with some whiteout. Then do some testing. Once you know at what throttle opening you are having the problem, you will be able to correct the problem in the carb the first time!

...they said to go out 2 turns and start from there, but what am i looking for?
Use this page as a guide:

http://www.thumperfaq.com/jetting.htm#PJ

It's for a 250F, but it's the same in principal.

The fuel screw/pilot jet needs to be set up so the bike runs right. If you have exhaust popping on decel, it could be lean fuel mixture at idle, but it can also indicate an air leak in the exhaust, commonly at the midpipe joint, or at the union of the header and cylinder head. If you have such a leak, trying to get rid of the pop with the fuel screw will get you an engine that's too rich.

Some popping is normal anyway, and unless it's really harsh and excessive, it hurts nothing.

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