KDXRIDER.NET

The stock gearing will give you 60 mph for 6 minutes with no problem at all.
200 or 220? I don't know, never had a 200. My 220 is one happy motor, though. Seems to me either one has the potential to give you what you want.

Lean roll seizure

Re: 'but I think you're talking about seizing the engine with a prolonged throttle letoff due to the rapid decrease in lubrication.'

Yep. Particularly when done immediately following extended hi-rpm operation.

re: 'it's generally a bad idea to let off the throttle from such a speed and attempt to coast to a stop.'


Two different situations that aren't much different.

The 'roll' part of 'lean roll' pertains to backing off on the throttle having once attained a hi-load speed: You wind it up through the gears, pin it in 6th until the bike is going as fast (mph) as it will go, then 'roll' off the throttle to the point you just maintain that speed. A dirtbike is likely geared pretty low..so there isn't a whole lot of WOT 6th gear pull (load) going on..still, don't pin the thing all the way to the top (get it good and hot) then sharply reduce the throttle.

More of a throttle chop situation...but don't do what juliend said, either. Compression braking (throttle chopped) after an extended hi-speed toot isn't good.

I'm not aware of any contention in the matter. Most that have ridden 2Ts for any length of time have had a brush with stickage in such situations. Of course, it's not of any importance if it hasn't happened to 'you'.

That doesn't make it less a 2T fact of life.

There's no reason a KDX can't run 60mph down the road for a while. I don't mean to infer I think it's a fragile setup. That doesn't mean you need to push your luck (60mph for 10 miles, drop the throttle, compression brake to stop, 30mph wind at your back).

Thanks again guys. The good news is I don't think I ever really chop the throttle and let the speed of the engine and the bike slow together - even on my 4Ts. I'm a "clutch/neutral/idle and blip the throttle constantly" kind of guy.

This bike intrigues me because it already has most of the mods I would have done myself for 220. Heavier fork springs, piston/rings, RB carb bore to 35mm, Boyesen reeds, FMF pipe and silencer, fatbars.

I'm trying a 2T cause I adjusted valves on my 4Ts about 1 time too many and I believe that lighter is righter when offroad.

Thanks again for the advice

Definitely ride the bike if possible, and see how it suits you. It's kind of hard to go wrong with a KDX. They're not "extreme" at anything, but they will do absolutely anything you want, and do it well enough to keep you grinning.

There is considerable difference between a bored carb and an RB modified carb.

The RB carb is 36mm, not 35. There is a plate in the downstream throat (reed side). You can see it from the upstream side easily enough if the slide is up.

I bring this up 'cuz you didn't mention an RB mod in your first post..and when you did, you said it was 35mm. I suppose that's what the owner said..in which case I'd wonder if in fact it had an RB modification at all. I would think he would at least know what size it was.

The OEM 33mm may well have been bored to 35mm by someone. That doesn't make it an RB carb.

Might as well know what you're getting....or not.

I was wrong on the carb - it's not an RB modded carb. The owner sent it to Freddette Racing and had it bored to 35mm. I was the one who assumed it was an RB carb as I had seen the name again and again.

Any thoughts on the Freddette Racing 33-35mm bore job?

Pretty sure it's just a bore and rejet....Basically making a stock 35mm carb as they are the same body.

johnyblaze wrote: Any thoughts on the Freddette Racing 33-35mm bore job?

There's a bit of a story about this.........

Dave O. (Canadian Dave) got Fredette to give the RB-modified PWK a try years back. Fredette didn't like it..said it was 'too picky' to jet. I don't know if part of that decision was a protection of his own carb work. I don't know how long Fredette has been boring the KDX220 33mm to 35mm. Maybe he started doing that after he ran one of RBs carbs? Don't know that either. I do know he didn't get on the RB bandwagon.

His loss.

An RB-modified carb consists of much more than making the big hole in the carb bigger. I don't know that a carb done by (or by way of?) Fredette consists of anything but the bore from 33 to 35.

The early RB-carbs had the plate installed in a different fashion from how they are put in now..they broke sometimes. Mine did, which gave me the 'opportunity' to run it with/without the plate on the same day, same environs, temps, barometric pressure..all that.

It didn't run 'fer diddle (compared to the plate being IN).

Which leads to my '..any thoughts..' on a Fredette bored carb:

canyncarvr wrote:BUPkis!

Having ridden a few KDX's at this point (both 200s and 220s) I'll know really quickly if I like it or not. The price is right, but if I don't like it - it'll be a no go.

One thing I've learned is that the KDX is a really common bike in these parts - so no reason to take one you don't like.

johnyblaze wrote: I need to get to and from the trails legally

I also have the BD DS kit on my 2001 KDX220 with a stock coil and LED tail light.
Works great for getting legalized and doing exactly what you described.

But don't plan to use the lights to ride after dark. It may be OK for getting home in a pinch. But don't count on enough light to do much of anything off-road. The battery is reletively small capacity, and you have to rev a lot to get close to the rated coil output. That may not be what the terrain requires, if you know what I mean.

I don't see a KDX kit on the BD site. It's something generic?

What's in it? If it has a battery, I presume it has a rectifier/DC regulator to replace the OEM AC regulator? What size is the battery (AH and physical)? If it can't keep the lights up when the coil input is below a 'charge' spec, it can't be much of a setup.

Thanks Barry - I won't be riding a KDX anywhere near dark. It'll really be only to get legal. Nice to know it can work even with the stock stator. Did you run blinkers off yours as well? We need all 4 blinkers, hi/low, front and rear brake and horn here in Maine.

I've tried night riding on several actual dualsports and even they need additional lighting for trailriding in the dark. My TE610 was dangerous on the road at anything over 25 mph in the dark - let alone on a trail. We have these things called moose and they're all over the place. Hitting one with a KDX definitely wouldn't come close to hurting one, but would be bad all the way around for the rider .

canyncarvr wrote:I don't see a KDX kit on the BD site. It's something generic?

I don't know why, maybe they don't have much call for it or something. Here's the installation:

http://www.bajadesigns.com/2005%20Web%2 ... lassic.pdf

I did not use their method of mounting for the rear signals and I replaced the tail light with a newer LED one.

canyncarvr wrote:What's in it? If it has a battery, I presume it has a rectifier/DC regulator to replace the OEM AC regulator? What size is the battery (AH and physical)? If it can't keep the lights up when the coil input is below a 'charge' spec, it can't be much of a setup.

Yep. New BD reg. Battery is a 700mah NiCd, sits on top of the airbox lid, and is prolly just enough to give the required 10 minutes duration of no-motor-tail-light-illumination to pass CHP/DMV. Pretty weak. Like I said, I think it's more for legality than for function. I suspect the stock coil output curve looks pretty curved.

johnyblaze wrote:Did you run blinkers off yours as well? We need all 4 blinkers, hi/low, front and rear brake and horn here in Maine.

Yeah, the BD kit has all four blinkers and all the rest, except only one brake switch. My kit had incandescent blinker bulbs. I think you can upgrade to LEDs from BD or just do it yourself. My kit came with an incandescent tail light as well, but I replaced with an LED.

The BD kit for my KX500 came with an LED tail light, incandescent blinkers. It was one of those quik-mount or ez-mounts. Another legal conformer with poor lighting performance.

Not even one AH? Gee...that's a whole lot less than I would have guessed.

At least it doesn't weigh much!

Thanks much for the install manual link!

BajaD wrote: Step 1. Get a degree in Mechanical and Electrical Engineering.

Impressive........

New KDX owner here!

The 98 220 is a good performer and a solid bike all around. Started easily, shifted well, good brakes, even a straight subframe. Almost no smoke at all when it was warmed up. Way more bike than I expected for $800. Owner was right on all counts.

Needs a kickstand, sprockets, rear fender (I'm thinking MX style) and a skidplate. Came with Devol rad guards the owner forgot to mention. Oh, yeah... I'll need to lose the Miami Vice purple fork boots cause that's just plain wrong.

The power is definitely shifted up more towards the mid and upper range than I expected - must be the rev pipe. Took me a few passes to get used to the hit but wheelies were exceptionally easy 1-3. For any of you who think the KDX is uncomfortable - go try a Husky TE610. This things way more comfy. Feels lighter and lower cg than my old KLX331 - may God rest her soul. The KLX had more down low but the KDX has it mid and top.

All in all a very happy new owner. Can't wait to hit the trails to see if I need to switch out the conventionals for a set of 98 KX250's I have in the garage.

Thanks to all for the info and tips on this thread.

Good Deal!

I think the KDX is one of the most comfy bikes I have ever rode besides the pig XL Honda I had.....

Good deal!

Happy Trails!