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Hi ya all,

The terain where we ride cosists of many whoops and lots of soft sea sand. I'm the only one with a 2 stroke and suffer in the soft stuff agains the 4 strokes due to a lack of torque.

The bike is a KDX 200 '06 model, has a standard stage 1 conversion that consists fo the full FMF Gnarly header pipe and exhaust, airbox mod and jetting. I still run the standard factory sprocket combination of 13 / 47.

Other than attempting a big bore conversion what else would you propose in an attempt to get a bit more bottom end torgue.

On the cheap, go to a 12t on the front. I've been running 12/49 and like it alot. Boyesen 607's help the low end throttle response quite a bit too.

Head cut by Ron at RBD?

Soft sand is tough on the KDX. I always feel like I am being abusive when trying to keep any speed up in the sand. Get your 4st buddies into the woods....

Which pipe do you have? Desert or woods?

Head cut will surely help. RB Carb mod will help low-end. Having a 225 built would help a lot. A 250cc MX bike would be on par w/ the 4-strokes.

I've often thought of simply running methanol in that environment as pinning the motor constantly is fine, but creates a lot of heat. The meth will help keep her cool while adding 8-10% power over the whole range. Would need spare carb for meth use. MPG gets cut in half.

Re: 'FMF Gnarly header pipe...'

That doesn't say what the pipe profile is. Torque (smaller diameter bell) or rev (larger). The smaller diameter pipe (sans other mods) will work better in the sand. WITH other mods..the rev pipe is perfectly suitable.

The 'standard' list of things to do on the 200 is mostly directed toward lower RPM band performance increase.

Use a high quality 2T oil. That will make more of a difference than you think.

Any reed change (except Boyesen's RadValve..it's complete crap) is an improvement. Boyesen power reeds (fiberglass...not the carbon reeds) help...a DeltaForce3 setup helps more.

A modified carb from RB-Designs is at the top of the list of modifications that will improve the bottom end pull of an 'H' 200. Send your head in at the same time!

You're not going to make the KDX200 run like a CRF..but you can go a long way in that direction from where you are.

shanana wrote: Other than attempting a big bore conversion what else would you propose in an attempt to get a bit more bottom end torgue.

If you're running the 'Rev' pipe try Fredette's Torque Ring; made a big difference on my '06.

Gosh guys, what a response...2 things.
1. I live in South Africa and ae therefore not as privileged as you guys when it comes to all the available mods or at least specialist in this aea. We do have guys that perform such funcitons but most of the time the additional parts are imported from the States and therefore it costs an arm and a leg. One thing I can definately do is the V-Force 3 RAD valve conversion and tweaking the sprocket combinations.

2. I should have been more specific on the pipe. The header pipe referred to as the Gnarly Gold Series used to be called the Torque pipe by FMF. They changed the name because the 'Torque' pipe did not consist of a 18g steel construction. The silencer I run is the Power Core II.

From an 2T OIL perspective, I currently use MOTUL 800 Off Road Racing Oil.

Re: 'One thing I can definately do is the V-Force 3 RAD valve conversion'

'Ya might want to re-read a couple things........

Re: 'The header pipe referred to as the Gnarly Gold Series used to be called the Torque pipe by FMF. They changed the name because the 'Torque' pipe did not consist of a 18g steel construction.'

Not quite right...but that's OK. The question was, 'what profile', and you answered that. The torque pipe is what you would want in your situation.

When was the last time you repacked your silencer? There's bottom end response to be had there if it's been too long since it's been serviced.

I don't have any idea what intercontinental shipping costs would be, or what customs hassles would be involved..but there have been instances of riders overseas shipping there carbs to a rider here..going from there back and forth to RB (inside the US at that point), then back overseas.

It's not generally a real cheap option......

A much better choice to simply BUY an already modified NEW carby from Ron..with the same buy it here, ship it there sort of dance goin' on.

Besides, if you sent your carb here, Ron would probably find that it was worn out and NOT something that he'd work with. THAT would be a waste of everybody's time and money.

So...just BUY one. A brandy new air striker!!

The head might not work out quite that way. 200 heads are harder to find than 220 heads around here, and buying a new one isn't a reasonable option.

Motul I recall being used by other KDXers that like it. I've never used it. At least you're not using SAE 10W-30 SG.

BTW...your exhaust doesn't leak anywhere, does it?

Oh...and when did you last check the KIPS?

Thanks for the reply CC...it's much appreiated. To answer some of your questions;

Re: 'When was the last time you repacked your silencer? There's bottom end response to be had there if it's been too long since it's been serviced. '

The bike has done about 40 hours since the last re-pack...what's the rule of thumb on the re-packing interville?

Re: 'A much better choice to simply BUY an already modified NEW carby from Ron..with the same buy it here, ship it there sort of dance goin' on. '

What would the approx costs be for the modified carb on the '06 200?

Re:'BTW...your exhaust doesn't leak anywhere, does it? '

Not at all. I check it every time I service the bike and there is definately no leaks.

One thing about the bike is that she goes like a bullet. Sweet throttle response and excelent mid and top range. All I need in my arsenal is a bit more grunt at the bottom in an attempt to proove to the 4t's that a 2t can at least play in the soft stuff alongside them...LOL

Re: 'what's the rule of thumb on the re-packing interville'

Rule of Thumb: Whenever it needs it.

Not being snotty 'bout it. There isn't a rule of thumb much. Well, once a year isn't likely enough, and once a month is likely too much. How often it's needed depends a lot on how its jetted, what it's packed with in the first place.

Re: 'What would the approx costs be for the modified carb on the '06 200?'

Lookee HERE!

I have no idea what import costs/duties would be for you. Riders in The Land of Oz have had parts sent to them from the states...labeled specifically as 'repair parts' or somesuch, the customs fees are considerably less. Check out RB-Designs shipping info..he does ship overseas.


You left out the KIPS.....