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Quick question regarding swapping my 220 33mm carb for the 200s 35mm, will this be a straight fit and good to go or will any changes need to be undertaken with the carb?

mechanically it will be a straight swap but the carb will need to be jetted to your bike

Thanks for the info, so it will require my 220 jets including the 220 jet needle, and that's it, float height won't need tampering with? Cheers

Carts you will want to use the 220 slide & needle in the mid position, also a larger main jet , either 152 or 155....the pilot jet 40 or even a 38 & tweek the air screw .
While the 200 carb is off just check the float height...theres a guy on ebay uk called `SMOKIN` who sells billet throttle & air screws for the kdx with easy to adjust knurled ends...no screwdriver needed ! I bought a pair for mine..

Cheers Cornish, nice to speak to you again! Yeah I have seen those on eBay & was thinking about getting the green ones, put them on my list for my next purchase.
Regarding the float height...should the 200 & 220 be the same spec?

Why would we want to use the 220 slide and needle in the 200 carb in this swap? I'm curious because I have a 200 carb waiting to swap into my kdx220.

Yes carts the float height is the same....

Regarding using the 220 slide & needle , some early 35mm kdx 200 carbs run a leaner cutaway on the slide & a different needle I.D , the 200 needle on the H series is also slightly different ( leaner by half a clip ) but the slide is the same ( its just easy to retain your 220 slide & needle when doing the swop, just raise the clip to the mid position ) ..I have tried the CEL & DEL needles in my 220 with the 33mm & 35mm carbs with a whole mix of jets & just couldn't get it to run that well ...I think these are more suited to the 200s style of porting.
The 35mm carb with correct jetting makes the 220 run well & gives the bike a helpful boost in the mid range with no loss in bottom end pull....I have since installed the 36mm carb of a 1990 kx125 while retaining the 220 needle & slide with even better results.
While the carb is off you can polish up the intake track ( not the bore toward the reed block but the rear toward the air filter ) & the rear of the slide too...

Cornish...wats ur thoughts on the kip spacers, & who sells them?

Just FYI:
I did a straight swap between my 200 (35mm) & 220 (33mm). Took the 200 carb & slide off and just installed it on the 220. Needle position, jetting, and everything else stayed the same... To say the least... the 220 with the 35mm carb really responded well to that change. Runs great and has power to GO...

Cheers,
SD

hello i own this kdx now and am using it for green laning, i'm getting rubbish tank range before hitting reserve about 50 miles not thrashing it. yesterday i used 9.5 l to my mate 5.5 l he was on my old 2007 gasgas 250

Depending on how it's ridden & the type of terrain you ride...80ish miles before reserve is about right....then around 20ish miles on reserve, so approx 100miles per tank..

Check the spark plug & air filter.... You should run these settings & go from there...

Check float height....

40:1 mix

38/40 pilot jet

152/155 main

Kdx 220 needle with the clip in the mid position ..

Air screw 1.5- 2 turns out...

Keep the air box lid on but just remove the snorkel & see how it goes

Why is there a smaller carb on a 220
Btw kips spacer (i think 6mm)on a 91kdx gives the kdx a little bit more power just before the valves open.... Thats what i've noticed
Also have 10 and 18mm spacer but that made it do weird things
I've made a stencil with paper and my dad made it with a cnc machine
But you can buy them on http://bdkraceeng.co.uk/tc/products.php?226

Basic Carb physics...a smaller diameter bore = better low end torque/response. A larger diameter = better top end response. As the 220 was designed and ported as a tractor, the smaller carb makes sense, but as noted above there are always gains to be made as long as you're ready to give something up in return.