Revvvvvvvvvvvvvvvvvvvv

Joined
Feb 1, 2001
Messages
44
Likes
0
#1
Hey guys, I want my KDX 220 to rev higher. I rode a ktm exc200 and I really liked the way the bike revs. I also noticed the way a friends wr200 revs. I also notice that a friends kdx 200 with the 36mm on it revs better than mine. They are getting so much more rpms than I am. Is this a carb mod or a porting job or both. Is there something that I do not know about? I have the normal mods Wiseco, fmf rev, boysen, air box. The bike runs great and I do not want to mess it up. This ktm is a 200 with a 38mm carb. I would like to have at least a 38mm on my 220. The best carb mod is a 36mm from RB by the threads I found. Is there something else out there? Something better?
 

fishhead

die you sycophant !
Joined
May 22, 2000
Messages
966
Likes
0
#2
in addition to the mods you listed I have my carb bored to 36, Freddete porting and the squish band modified on the head and a Rad valve and its pretty rev happy and i didn't loose any bottom end.
My buddy with a ktm 200 doesn't want to drag race any more :p Not everyone has been able to get real good results with plated carbs on the 220. I found it to be more trouble than it was worth and pulled the plate and jetted per usual 200 specs and a # 38 pilot and it rips now and runs clean.I think some guys here on the forum are working on 38 for their kdx's but I haven't heard how thats gone.
 

Sage

dirtbike riding roadracer
Joined
Mar 28, 2001
Messages
621
Likes
0
#3
I've been using a 38 for about a year & a half, no problems. If you build it, it will rev! I can't say who to call or its spam but if you follow the link that C.Dave posted for the pipe sale you might find him. See Ya............

Dyno #'s coming, I'm waiting for my dyno.
 
Joined
Apr 22, 2001
Messages
164
Likes
0
#4
More rev

I don't know if it would help but I have an FMF Burly Rev pipe off a 1999 220 that I am not using, it has one of the FRP pipe guards on it. If you are interested it is yours for $100. No dents, looks good.
 
Joined
Feb 1, 2001
Messages
44
Likes
0
#5
Thanks Mike, I already have a FMF rev. I like the pipe. You should not have any problem selling it. Good Luck

Thanks Sage, Waiting for the dyno info and a little better idea of what is involved in this 38mm mod. I do not have the time to play around with little parts and pieces from here and there. I need a concise plan and the parts on hand. Time involved in gathering parts and doing getting the mod completed is of high importance. I am going to do something soon. Let me know if there is a package available. I may get a porting job done at the same time if that is the solution to max performance.
 

acutemp

Lifetime Sponsor
Joined
Sep 4, 1999
Messages
197
Likes
0
#6
Greenman, The 38mm carb will bolt right in with a larger reed side clamp being the only needed part. IMO it will probably be to much carb for a stock ported motor. I have both a modified 36mm and a modified 39mm carbs that I run on my 200 that has had both porting and head work done to it. I still have some jetting to dial in on the 39mm but it does pull quite a bit harder and farther on top than the 36mm, but is not quite as crisp on the bottom. If you are looking for top end, get some motor work done and give the big carb a go. :) Good luck and let us know how it goes.--Dan
 
Joined
Feb 1, 2001
Messages
44
Likes
0
#7
Dan, What carb is this 38mm carb. Is this a bore out of some other carb or something I can purchase. Is the reed side boot able to fit the new carb and the hose clamp the only thing that needs to be replaced? Do you have some initial jetting info for the 38mm? I know that you are running a KDX 200 and I am running a 220, but the jetting you have should at least give me a place to start if not close to ideal.

I made up my mind to get the mo-better everywhere porting job from Eric Gorr at the same time as the carb mod. This 38mm mod sounds like the one for me. All I need now is where to get my hands on one.

Thanks for the info guys.
 
Joined
Mar 23, 2001
Messages
56
Likes
0
#8
I think I'd potentially be interested :think in that pipe for $100. I've got a 01 KDX220 that I'm looking to hop up a bit. Have stock everything except bars though. Would I need the Wiseco top end job just to run the pipe? If that's the case I'd probably wait on a pipe until the top end is needed. Maybe just change gearing and forks or something instead.
 
Joined
Jun 18, 2001
Messages
11
Likes
0
#9
You can slap that pipe on ASAP, Running the pipe has absolutely nothing to
really do with the top end. Go for the pipe you'll be impressed with the gain
and the loss in weight.
 
Joined
Feb 1, 2001
Messages
44
Likes
0
#12
Speed is not the problem. I want to get more distance on every gear shift. If the engine gets another 1500 to 2000 rpms then I will not loose ground in the straithts to those higher reving bikes. I also have a hill climb in WV that I need more rev to get up. It is a loose coal slag pile at about 40 degrees and 250 feet long. I noticed that the stock kdx's that we had did not even make it half way up the hill. No matter what they tried the bikes just died half way up the hill. The modified kdx's did well but mine lost it's mojo too early. The modified 200 had enough mojo. The rider did not have enough mojo. Just for you Kelvinkdx.

The 200 has a 36 mm carb and achieves higher rpm's and that was the difference. I also want to make the step away from trail tuning and to MX tuning. My skill level allows that now. A year ago I would not have concidered this.

Dan, Let me know what carb you are using.... Please!!!!!
 

acutemp

Lifetime Sponsor
Joined
Sep 4, 1999
Messages
197
Likes
0
#13
Greenman,
Any large body pwk carb should fit fine, the carb that I am working with is a 39mm that was originally off of a kx 500. It is not stock as I have had it modified by Ron at RB Design and have done some extra work to it myself. I still have my stock carb, that has also be reworked so I can always put it back on if I need the added low end responce. I would be sure and talk to Eric first if he is going to do your motor work and get his input. For good results you must build your motor as a package or you will just end up with frustration. The larger carb is a top end mod which should in most cases be used with other mods that are geared in the same direction. Putting a big carb on a bike that is in other ways setup for all around power might just end up losing power everywhere. I would be glad to help with your jetting if you go the big carb route, my experience is that the larger the carb the harder it is to dial in the jetting. If the thought of spending the day jetting instead of ridding doesn't make you sqeamish then it could be well worth your while, but if it does you would be better off going with a bored out stock carb as you have much more data to work with. Right now my jetting is a 50 pilot/ 178 main/ #7 slide/ NOZH #3 with HP2 at 32-1 mixed with 110 Trick fuel in my kdx. The big carb is also a tight fit so jetting it is a bit more of a hassle. I will e-mail you a couple of pics that compare my 2 carbs. Good luck with your quest for more HP:) --Dan
 
Joined
Feb 1, 2001
Messages
44
Likes
0
#14
Thanks Dan, I am going to take your advice and go with Eric's suggestions. I do not mind a day lost to jetting. Sometimes it is quite a rush when you finally let the Jeanie out of the bottle by getting the jetting just right. I would rather get this mod up and running without too much tuning. Some of the best riding of the year is coming up and I don't want to mess my bike up for too long.
I will get Eric to recommend a porting and carb mod to work together. Over the winter I am going to look for the biggest carb I can get on the bike and do some experiments. Should be fun ripping the back yard up next spring.:p
 

KelvinKDX

Lifetime Sponsor
Joined
Aug 25, 2000
Messages
1,621
Likes
0
#15
Green(Girlie)Man,

Ouch!! The truth hurts :( (but I will improve and you will still be the Girlie Man):confused:

Maybe we should put an end to this madness and spend the end of the season looking for a good KX250 for you. I know you and you will never be satisfied until you put knobbies on your Nija and hit the trails!:scream: