andrew

Member
Aug 7, 1999
278
0
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,

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Andrew
96 KDX200
remember: skin grows back!
 

TooFastTim

Member
Dec 28, 2000
4
0
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

~SPONSOR~
Jun 8, 1999
627
0
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.

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Mikeb
1998 KDX200  
http://www.justkdx.dirtrider.net
 

andrew

Member
Aug 7, 1999
278
0
SO, perhaps it's more common than I thought !

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

Cheers

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Andrew
96 KDX200
remember: skin grows back!
 

smb_racing

Master of None
LIFETIME SPONSOR
Jul 31, 2000
2,085
0
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.

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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
Apr 28, 1999
1,202
0
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


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

www.justkdx.dirtrider.net
 

Cordova

Member
Sep 8, 2000
15
0
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.

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joe woj

Member
Oct 29, 1999
58
0
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!

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jcollins

Member
Jun 20, 2000
2
0
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


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MN KDXer

Registered
Jun 7, 1999
194
0
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.

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-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!!"
 

cstager

Member
Apr 5, 2000
3
0
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

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jcollins

Member
Jun 20, 2000
2
0
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


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WoodsRider

Sponsoring Member<BR>Club Moderator
Damn Yankees
Oct 13, 1999
2,812
0
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
 

NDRO

Member
Jan 6, 2001
128
0
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.
 

MN KDXer

Registered
Jun 7, 1999
194
0
I remember some more about my cable... On my particular 220's cable, there was some excess flash on the lug at the twist grip end of the throttle cable. Under close inspection, this flash could catch on the throttle housing, or cause the lug to bind, etc. It was certainly a possibility for my bike to have a stuck throttle with those particular components.

I removed the described flash, and never had a problem with the 220 all last year.

The other mentioned potential causes are certainly possibilites as well. But, as one member pointed out, this throttle sticking seems to be a newer KDX thing.



------------------
-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!!"
 

smb_racing

Master of None
LIFETIME SPONSOR
Jul 31, 2000
2,085
0
jcollins,
I loved my old Can-Am, truly a work of art but I'm having problems with mine, somehow the connecting rod is bent and I'm working towards getting all the parts to replace, for now the beast sits, awaiting $400 of connecting rod, bearings, seals, and k/s shaft to make it good as new. Want to see some photos? doesn't it bring back memories :)
http://albums.photopoint.com/j/AlbumIndex?u=1429550&a=10769107&f=0



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

BoyKDX

Member
Apr 12, 2001
1
0
WOW it feels good not to be alone. I've had lots of run-ins with the runaway throttle!
When I 1st got the bike the throttle would take off on me and I had to dump the bike and grab the kill switch till it totally died. Happened at Budd's Creek in the hare scramble Yikes!!!. I found out my head bolts were loose and it started sucking air in. Last year I did an enduro in south Jersey (sandy) ever since then throttle would stick randomly. Even when I went slow. I took the carb apart and the needle was kinda nicked up. I replaced that and cleaned everything. I'm putting it back together this week and I'm scared as hell to ride it but I'm prayin it's fixed. One friend said watch the routing of the cable under the gas tank sometimes it gets hung up there. He had his 94 take off on a woop and fly up into a tree luckily without him! Then the bike got stolen in Philadelphia. I'm sure the crooks got punished by that one.

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Gonna ride til I drop!!!

[This message has been edited by BoyKDX (edited 04-12-2001).]

[This message has been edited by BoyKDX (edited 04-12-2001).]
 

andrew

Member
Aug 7, 1999
278
0
Well, I've been away for a week and WOW, look at the response ! Looks like it's a LOT more common than I suspected.

Sifting through all the replies, I have to agree with quite a few of them, but the idea that stands out most is the one about the casting flashes in the throttle body. It seems to meit has to be something at that end rather than the carby end as the definate clunk as the slide hits the bottom seems to suggest nothing much is wrong there.

I have already replaced my cable, and noticed that the handlebar under the throttle tube had been well greased; in fact it had turned to paste with all the dust and crap stuck to it. Even though it SEEMED to work ok, I couldn't help but wonder if it wasn't working quite as well as it should, so I cleaned it all thoroughly and reassembled WITHOUT grease like the manual sez...I'm riding tomorrow so I'll let you know what happens.

Fingers crossed...

Cheers

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

Westex

Member
Dec 21, 2000
30
0
I had what I thought was this problem earlier this year. It was in February and we were at the first enduro of the year (Renegade). The bikes had been outside all night and it was very cold. I started my son's TTR to let it warm up and then I started my 98 220. As soon as the bike started it went to full throttle. I immediately killed the bike because I didn't want it to sieze. I messed with the throttle and started it again......
..same thing, the engine was revving. Now I was starting to panic because the race was going to start soon. I was convinced that the slide was sticking so I took it apart and found nothing. Then a friend suggested I take the bowl off and inspect everything there. This is what I found. There was a layer of ice 1/16" thick covering the bottom of the float bowl. A small piece of the ice had broken loose and was partially blocking the main jet. I cleaned out all of the ice and the problem was solved. I've since talked to people who say they've had to take a blow drier and thaw out their carbs.
This same problem has killed many pilots of single engine aircraft. Ice forms in thier carburators and kills the engine. I believe also that most small airplanes have carburator heaters built into them.
I have also seen a small amount of grease from the air filter get sucked into the carb and block the main jet causing the same problem. The bike is running super lean but it seems as if it is stuck at full throttle.
Anyway see what you think about this and try to remember if it was a cold morning when this happend to "yall."

Happy Trails,
Keith

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When I'm not riding, I'm thinking about riding.

[This message has been edited by Westex (edited 04-15-2001).]
 

andrew

Member
Aug 7, 1999
278
0
That's an interesting theory Westex, I haven't actually had the bowl off my carby for a while so perhaps there's a bit of grit in there occasionally getting sucked up to the mainjet, not getting in but falling back down...

No, it's not possible for ice to form here in Darwin (far north Australia) except in the beer fridge...

The good news is that today I gave my bike a good hard flogging in the swamps - water and mud and weed in every orifice (yes, even mine!) and not a hint of a sticking throttle...

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Andrew
96 KDX200
remember: skin grows back!
 

OLD-N-SLOW

Member
Nov 21, 2000
168
0
While cleaning my bike yesterday I had a thought.(that does not happen very often so I took note.)I wonder if a over oiled air filter could allow some oil to be sucked on to the carb slide and thus preventing it from fully closing. I know the bel-ray filter oil I use is very stickey. Do you all
who have had a stuck throttle use a lot of oil on your filter?
Just thinkin'....... This has not happened to me , but it sounds very scary.

Steve 01kdx200

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jeffw

Member
Nov 27, 2001
172
0
Bump. This is an important thread and I can't remember the subject being discussed in a while.

This happened to me twice at a HS a few weeks ago, both times happened out in fields right after woods sections. The second time was just a blip but the first time the bike stuck WFO. Before I got it killed I remember the throtle action being slack like the carb spring was broke. After the bike stopped it freed up.

From the way it felt I don't think the problem was in the cable or throttle tube but rather the slide was stuck. When I got home I took the carb apart and there was dirt on the bottom of the bowl and more oozing into the top of the bowl from one of the vent tubes. I sprayed it all out with carb cleaner, took off the vent tubes, and rinsed them with gas.

What I think happened is after the rough woods sections, dirt in the bowl got churned up and some sucked through the main jet, sticking the needle to the jet and holding the slide open. The dirt entered through the vent tubes, I guess.

I've heard of people running their vent tubes into a miny filter inside the air box. Any body have any other suggestions on rerouting these tubes? Do they have to be lower than the bowl?
 

Duneman

~SPONSOR~
Jun 16, 1999
218
0
people please listen, KDX's have air leak problems on the ignition side of the crank, it sucks air into the crank and you get way to my Oxegyn for the amount of fuel witch results in a more than wide open situwation cause you have more power than just full throttle, and it only does it at random that is why you can't duplicate it on the bike stand. I almost killed my self twice on mine, I cleared a 70 triple with a 40 foot take off and flipped the bike in the air it was horrible and I was out for along time, trust me it's not the CARB or THROTTLE!
 
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