RB Designs LLC
Machine Shop Services ~ Motorcycle ~ ATV ~ PWC ~ Small Engine ~ Custom Parts Machining
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Carb Mods
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KDX 200-220
Carb Mods
The Original RB carb mod!
This modification is a great enhancement to both power and ride-ability!
Our carb mod for the KDX 200 and 220 has proven it self for well over a decade now to be a winner! It will give you a great deal more throttle control and response and useable power throughout the entire RPM range with more low end torque and more top end power. This modification will allow you to easily fine tune your engine for whatever your riding needs are.

Your carb will come back to you pre-jetted and ready to go right out of the box. We do our best to get the jetting very close to your riding needs and supply optional jets for fine tuning for different riding conditions. Our mods really bring the mixture screw into play, fine tuning for different or changing weather conditions or different altitudes can be as simple as a small tweak with the mixture screw.

Our carb mod works best with the air box lid removed, aftermarket pipe and maybe some aftermarket reeds like the inexpensive Boyesen 607's. Note: the 220's lack compression and really respond much better with a head mod too.
These are the mods performed to your carb:

Bore Carb to 36 mm (gives you more mid range and top end)
Install Divider-Plate (gives that great low end response and throttle feel)
Modify Slide (don't forget to send your slide and needle assembly)
Install New Needle (gives the carb its personality)
Modify Jet Block (helps with preformance)
Modify Low Speed Circuitry (this and the other mods really bring the mixture screw into play. With very small adjustments you can make big changes to the low speed allowing you to keep running clean and crisp with changing altitudes and weather conditions during a ride.

Requirements on getting your carb mod done by RB Designs (KDX);

First and foremost, this is not a carb cleaning service! We do not clean carbs or fix problem or damaged carbs. These are performance enhancements done only to great condition and spotlessly clean carbs without issues.

Before sending your carb to us, you must take it apart and inspect it for water contamination or old stale gas and green or yellowish residue. Even if it appears to be in clean condition, you still need to give it a good cleaning inside and out and make sure it is totally gas free.

Also when you have the carb apart you need to inspect the float pin fit where it goes through the two pivot towers on the main carb body and make sure there is no slop in the fit. And make sure there is no plating coming off the slide. Slop or ware in either one of the areas could mean the carb is not suitable for modification. You will need to remove all hoses (do not send). You need to send the slide and needle assembly with your carb. Your carb is going to need $20.00 replacement rubber parts (so you should send that amount with your payment).

If cleaning is not in your comfort zone, you should take it to a reliable shop and have them clean it for you. (We will not work on dirty carbs!).

Please note; these carb mods do require some good mechanical skills and fine tuning experience….

$180.00 = Carb Mod  (includes return shipping and handling in USA only)
Don't forget to send the additional $20.00 for the necessary replacement rubber parts
ACCESSORIES for your carb mod 
Payment and Shipping Instructions
Please feel free to Contact Us for more information.
NEW Modified replacement carbs for your KDX 200-220