Sticking Throttle

Joined
Aug 7, 1999
Messages
278
Likes
0
#1
Occasionally my throttle will stick open, usually when I've been on the pipe. If I pull the clutch in it normally unsticks within a couple of seconds. It only occurs intermitently and I can't reproduce the problem with the bike on the stand.
I've checked the slide and its all OK, no foreign debris to make it stick, and the needle isn't coming too far up at WOT. Of course I've checked for frays etc, cable seems to operate smoothly.
The only thing I can think of is that last time I had a frayed cable I got a new cable put inside the old case - maybe I've got a minute kink somewhere.

Anyway, I've ordered a complete new cable assembly in the hope this will cure it.

Has anyone else experienced this problem, and if so what was causing it??

Cheers,

------------------
Andrew
96 KDX200
remember: skin grows back!
 
Joined
Dec 28, 2000
Messages
4
Likes
0
#2
I've noticed with nearly all the bikes of owned. It's terrifying. The only explanation I can come up with is that the slide might become a little worn and oscillate inside the carb causing it to stay open. An analogy would be putting a golf ball in a slihtly larger diamete tube. There's a frequency at which uou can shake the tube from side to side which will cause the ball to stay in the same place in the tube.

Any other ideas out there?

TooFastTim
('01 EC250)
('01 TXT250)
 

Mikeb

Subscriber
Joined
Jun 8, 1999
Messages
627
Likes
0
#3
OH YEA i have experinced htis also .. 2nd gear uphill ... bike went wide open into a tree. Luckily I escaped unharmed but I did put a nice dent in the pipe. Dave also had this happen to him. Bike flipped over backwards and bent everything from the seat back. Check this out: http://www.justkdx.dirtrider.net/images/wreck2lg.jpg He also never got it figured out either.

I went through EVERYTHING and never did find out what was wrong. I found a 2 grains of sand in the float bowl and a very slight scratch on the slide. I kinda chalked it up to that. I also replaced the throttle cable. and SO FAR ( knock on wood ) it has not reappeared.

------------------
Mikeb
1998 KDX200  
http://www.justkdx.dirtrider.net
 
Joined
Aug 7, 1999
Messages
278
Likes
0
#4
SO, perhaps it's more common than I thought !

What do YOU think, Canadian Dave?? Any Ideas ?

Cheers

------------------
Andrew
96 KDX200
remember: skin grows back!
 

smb_racing

Master of None
Joined
Jul 31, 2000
Messages
2,085
Likes
0
#5
I also have had this happen, 2nd gear handful and tried to back off but the bike would have none of it, took a set of stairs off of a building :eek: a friend said there was no way the throttle stuck on me but the contusions on my shin said otherwise. Although thankfully it hasn't happened since I'm still wondering.

------------------
Jeff-
'84 Can-Am ASE 250 (brutally fast rat bike)
'93 Kawasaki KDX200 (big bore kit, A-Loop suspension, FMF pipe)
 

Canadian Dave

Super Power AssClown
Joined
Apr 28, 1999
Messages
1,202
Likes
0
#6
It’s happened to me a couple times, both resulted in some serious damage. Here’s my advice. Remove the carb and pull it apart. Remove the pilot and main jet and pull out the slide and needle. Clean everything very well with carb cleaner and inspect the jets for obstructions. Set the carb aside and remove the air box from the bike. Remove the filter and take the air box to the car wash and clean it well inside and out.

The junction between the air box and boot can leak dust/dirt so you want to make sure its well sealed. Disassemble the air box , clean the mating surfaces with carb cleaner and reassemble with a thin layer of silicone sealant. This will help insure its dust proof.

David


------------------
Let's bust big . . . I don't think so. Let's bust bark! Now you're talking!

www.justkdx.dirtrider.net
 
Joined
Sep 8, 2000
Messages
15
Likes
0
#7
Hey, I had the same problem. The good guys here at the website told me how to fix it right up. What they told me was to take apart my Carb and look down the slide, make sure the slide is in correctly. Go to your bike, and pull on the trottle, listen for any clicks during the twist. If there is one or two, just check for the slide do be in right. If that isnt the case then just clean out the carb. Thats my 2 cents.
----------------------------------------------------------------------------------------------
00'KDX 200
I may ROCK, but im not made STONE.

------------------
 
Joined
Oct 29, 1999
Messages
58
Likes
0
#8
i gotta agree with tim on this one the only thing i can figure, "less the cable binding" is a worn throttle plate in the carb the occlition of the engine running holding it in place thus holding open the throttle, whats weird is it would have to overcome the pressure of the return spring, ive never had the adventure of this, but i can imagine it to be a scary dangerous handful!

------------------
 
Joined
Jun 20, 2000
Messages
2
Likes
0
#9
Andrew,
Had the same thing happen twice last season. Both times I got lucky, but it was close to real bad news. The last time it happend was the last ride of 2000. I haven't had it out this year (still 3' feet of snow in NH). Over the winter I sealed the air box / carb boot juntion, and I hope that takes care of it. As far as a worn slide??? my bike was bought new last year (220 2K). After reading all these post with the same problem, it sounds like some kind of design flaw. I think the real issue is a decent trail bike goes for about $6K plus, we paid less than $4K for these. And in the end you get what you paid for. If you find anything else out please let me know. At this point I'm apperhensive about riding the thing. I've owned a lot of dirt bikes over the past 25 years and never had this happen with them.
Good Luck!
JC


------------------
 

MN KDXer

Registered
Joined
Jun 7, 1999
Messages
194
Likes
0
#10
I am of the belief that the problem lies within the twist grip. I had the problem happen once with my 95 KDX200 some years ago. As best I recall within the panic, the throttle locked solid.

Close inspection of the throttle twist housing will reveal that if the cable is somewhat loose, there is a possibility for the cable lug to shift and catch on the housing. If I remember corrrectly, there is a little bit of casting flash which just might be the culprit.

------------------
-01 RM250 (mine) & 01 RM125 (kid's)
-Senior A Enduro and Hare Scramble Rider.
"Yep, that 14 yr old A Class rider is MY kid; He learned to ride from ME!!"
 
Joined
Apr 5, 2000
Messages
3
Likes
0
#12
Yeah I had this on my 93 RMX250. The carb, airbox, and filter clean as a whistle but the damn thing would stick after big whoops or a jump. I went through three throttle cables and numerous disassemblies. I drove with two fingers on the bars, two on the clutch and thumb on the kill switch. Over the winter I replaced the throttle cable with the OEM part and found several crutical bits of info. There were some score marks on the jet needle. Leads me to beleive that a piece of sand or dirt got jammed in between the needle and needle jet. Makes sense why the it would stick here as clearance between the two is minimal. I also noticed the breather tubes for the carb were clogged with dirt. I'm thinking that a big bump, jump, whoop would knock some of the dirt from the clogged breather tube into the jet. Anyways, one ride so far has been stick free.

Keep the thumb by the kill switch

------------------
 
Joined
Jun 20, 2000
Messages
2
Likes
0
#13
To all,
I think we may be on to something here. This post that Andrew started could be one of the most important on the site. If we figure out what's going on we may even save someones life. I know that sounds a little stong, but for me it was that close. If anyone reading these post thinks he has the answer to the sticking KDX throttle, please let us know. It seems like most of the post are from owners of later model bikes? Maybe it's an issue with the carb Mfg?
Dave,
Any thoughts?
Jeff,
Your right about the Can-Am. I had the 83 MX-250, it was the best bike I ever owned!!. And the throttle didn't stick on that bike, did it.
JC


------------------
 

WoodsRider

Sponsoring Member<BR>Club Moderator
Damn Yankees
Joined
Oct 13, 1999
Messages
2,812
Likes
0
#14
I've had stuck throttle problems on three of the bikes I've owned. Here are some tips:
1) Grease the throttle tube.
2) Lube the throttle cable often and replace it regularly.
3) Make sure the cable is not pinched or bound when turning the bars from side to side.
4) Use an in-line fuel filter to prevent dirt in the tank from entering the carburetor.
5) Seal the airbox at the boot junction with silicone sealer.
6) Inspect the airbox and boot for any damage, cracks or holes.
7) Make sure the hose clamps on the carburetor are properly tightened.

------------------
'98 GasGas EC250
'01 Sponsors: me, myself, I
 
Joined
Jan 6, 2001
Messages
128
Likes
0
#15
One thing that I found was that when I switched to a different handlebar, the tube was rubbing slightly on the OD of the bar.

I ended up sanding the OD of the bar and the ID of the tube with 220 paper.