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i have a 1992 kdx 250 and i want to know all the mods to get most hp out of the bike. Reeds, Carb work , exaust, or anything else and who is the best to send my cyllinder off to get ported out and polished by

The KDX250 shares its reed assembly with the '89+ KX500. I like the Vforce III reeds but the RAD Valve is supposed to be good as well. For carb I would either suggest an RB modified 38mm Airstryker carb or possibly a Lectron or APT Smartcarb. There is not really any choice when it comes to pipes. Just find a good one (FMF, PC, etc) and run it. As for porting, I would go with Eric Gorr. He gives you three options, more low, more high, or more everywhere. BTW, he also offers a 265cc big bore kit as well! Good luck and keep us posted if you decide to build it!

The first mod I did was kx 250 thin head gasket, fatty pipe and a lot of messing with the jetting. I plan on a gorr port job this summer.

Okay I will look into them I'm looking into taking it apart next weekend and will probably send it to him I see a lot of good reviews about him. And I may go with the vforce 3 reeds if anyone thinks different let me know

Do they make VForce 3 reed assemblies for a KDX250?

Jason wrote:Do they make VForce 3 reed assemblies for a KDX250?

Not specifically. The do make them for the KX500 (which shares the same reed assembly) or at least the last time I checked about a year ago.

OK. I was thinking V Force 2 was the most recent.

Can I get a pro curcuit platinum for my kdx 250 and what website if anyone can find it

Has anyone heard of putting a 6 speed transmission in a 1992 kdx 250 and if so could you tell me how to and what the cost would be

JustinMiles wrote:Can I get a pro curcuit platinum for my kdx 250 and what website if anyone can find it

I don't think so but check Pro Circuit's website.

JustinMiles wrote:Has anyone heard of putting a 6 speed transmission in a 1992 kdx 250 and if so could you tell me how to and what the cost would be

No, there is no way feasible, that I know of, to put a six speed in the KDX250. Why would you need or want to?

I just always liked 6 gears feels like I always need another gear when I'm going on it , so it's no bottom end swap I can do I know the klx 250 ha a 6 speed any possible way my top end would fit on it

Roy Adams where did you get the thin head gaskets from and what machine did you get it from

JustinMiles wrote:I just always liked 6 gears feels like I always need another gear when I'm going on it , so it's no bottom end swap I can do I know the klx 250 ha a 6 speed any possible way my top end would fit on it

The KLX250 (4 stroke) is a completely different design than the KDX250. I know I have had my 250 up to almost 85mph and it still had plenty left even with only 5 gears. Remember, it is a 2 stroke, they are meant to be revved!

JustinMiles wrote:Roy Adams where did you get the thin head gaskets from and what machine did you get it from

You want one from the '88-'91 KX250. Just make sure you order the one that is .26 thickness and not the .46. BTW, you have read this thread, yes? http://kdxrider.net/forums/viewtopic.php?f=134&t=13319

Yep the 88 91 kx 250 metal gasket. It make it even more of a beast. make shure you run premium fuel in it if you run that gasket.The kdx 5 speed wide ratio is great . 5th gear is overdrive allready. If you get your bike jetting dialed in you will be amazed. What jetting are you running now.

idk exactly off hand but my buddy works on them and we installed leaner jets and it made a world of a difference it rips a lot better now but i know its like 3 or 4 numbers smaller than stock size jetting

and by premuim fuek do you mean 93 octane (thats what i run) or the 110 octane

Yea 93. To get mine jetted I had to go to a 35 pilot 2 turns out on screw, 155 main, #6 slide and two needle sizes leaner. I have head gasket,fmf fatty pipe, fmf turbine core silencer, boysen reeds and an opened up air box lid. And I recently stuck the engine on a rm 250 chassis and installed a auto clutch. Now I have a tru woods weapon. If I rode open roads I would have just kept the kdx chassis it was better in a straight line but sucked on single track where I ride

When you mean open the air box you mean you took the lid off? Because mine has no lid on it already

Could someone give me a web address of the head gasket .26 thickness so I make sure I get the right one thanks

I just cut my top open so I could leave my cdi box bolted to the lid. Gasket p/n 11004-1236 you can find them on eBay or kawi dealer.