wrecked the 500. slide sticking at the top of the carb. why?

[KXT500]

ok i have a carb problem that tried to kill me.  the slide is sticking in the top of the carb. when i loosen the cap it falls back down.

should something retain the throttle cable to the top of the carb? it has the adjusting screw and lock nut on top of the carb hat and the cable has a rubber boot but it easily slips in and out of the adjusting screw.



here is the story.

i have been building a new kx500 powered three wheeler to sand drag. Thursday i bled the brakes and went for a little ride. i was in 3rd putting along blipping the throttle when it stuck wide open. the bike went into a instant wheely and was heading at a barbed wire fence about 100' away. i was barely hanging on do 50mph or so. with about 1 second between the fence and myself. I bailed off.

Next thing i know i hit something solid and heard the three wheeler screaming at WOT. it went through 4 strands fo barb wire, jumped over another fence and then went back though it. i seen it doing back flipps in the air before it finally fell on its side and died. not sure if the motor blew or if it ran out of gas.

the forks are bent, frame bent, grab bar bent, pipe smashed, pegs bent, master cylinder busted, front wheel bent and the caliper is busted, new cables are trashed and more.

i barrel rolled, flipped, and skipped for 75' or so and hit the fence. I have a huge bruise on my leg and lots of rash.  my hands and wrist hurt from flapping on the ground and my fingers are swollen.

my 3 year daughter seen the whole thing. she rode her power wheels jeep about 100 yards out to me. and said "Daddy that was cool!!! your 3 wheeler was riding by itself and flying through the air!!!

i asked her to go get mommy for daddy. i was hurting.  :help:

here are some pics

where it went though

where i stopped

i set it up for this pic

the 2nd fence it jumped and then went back through

some of the damage









my help getting it back to the shop

[KXcam22]

Ah nothing like the unexpected full-power delivery of a KX to make you feel mortal (and give you a sphincter pucker to boot). Seriously, I hope you are ok.  I am assuming that the donor motor and carb may  have a few miles on it so there could be some unexpected/unnoticed wear in the carb& slide possibly.  Hard to give an exact anwswer but I would inspect for:
1. binding in the locating pin
2. ovaling (or squasehed a bit) of the slide bore
3. hidden cable damage right at the adjuster where it enters the carb.

Is your cable one that has the 90 degree metal tube on the end or not?


Hope this helps. I am sure others will have some more/better ideas. Cam.

[tharden]

That sucks!  Well, at least you got out of it with just a dis configured trike, as that could have been a hole lot worse for you.  The three wheeler does look fun to ride and it looks like the damage done to the frame is repairable and the front forks can be replaced.  This give you the opportunity to take some inverted forks and stick them on there.  As for the carb I agree with Kxcam22.  Also if you have a leak in the air filter tube you can suck debris and that can hang up the slide.  Also check the throttle assembly on the handle bar. 

[KXT500]

it was a new cable. it is trash now.

what year has the 90 bend on top? that would be nice if it operates smooth. the carb is all clean and no apparent wear. i am sad to say that the donor bike was pretty nice and fairly low hour. the rear frame had cracked at the lower shock mount and the previous owner took a spill. i will be inspecting it more on monday but for now i am content to lay around and take more advil 


i will say it seems to hit harder then my cr500 powered trike. i do not think the cr500 will loop out in 3rd gear like this one did. they both have +6" swingers.

[KXT500]

one more question.

should something retain the throttle cable to the top of the carb? it has the adjusting screw and lock nut on top of the carb hat and the cable has a rubber boot but it easily slips in and out of the adjusting screw.

[Rd]

If it is like a 250 a clip holds it into the brass peice on top of the carb. There is a slot on the brass piece and a notch on the cable end. The tube going into the carb broke about 4weeks ago on my sons 250 causing it to hang. It happened when I was on the face of a double. I compressed very hard on landing and also broke my tail bone so I feel your pain. Be safe

[DEZADX]

Sorry to hear of your unfortunate dismount.  Your injuries look like they will heal right quick.   I can't offer much help in diagnosing the probable cause of the throttle sticking and sending your ride into warp-drive through the fence line.  As I read your post, I thought how bad you must feel after the time and energy already spent on your project.  Then I read what your daughter said,........and d@mn near spit up dinner.  I was laughing so hard I found it hard to breathe.  My better half comes in asking what in the heck is so funny. I let her read your story........

Then I get chastised for making fun of your misfortune.  Hummmm.  Women....go figure.

Again, hope you get better soon.  Your daughter is priceless.  And if you give up your day job, you should maybe take up adventure writing.

Well Done !

[KXcam22]

In the old days on my euro bikes it was normal to lockwire the throttle cable to the carb as a precaution. Cam.

[KXT500]

my daughter is a trip. she was telling her Papa about it and said she wanted to see me do it again.     she does not realize that it hurt, she just thought daddy looked looked all those youtube videos 


we i did a little more research on the carb last night. i had another 39mm pwk laying around with a throttle hooked up. i swapped the entire cable/top/spring/slide assemblies between the two.   the wreck carb slide stuck in the new carb. the new slide did not stick in the wreck carb.

it has something to do with the wrecked slide/spring/top assembly. the only difference that i can see is that the wrecked carb has a little bushing that holds the cable in place. the other one did not have this.

it also only happens when the top is on the carb very snuggly. if it is off or left loose it wont bind. i think the spring is binding in the slide pushing it to one side.

[turtle22]

i had kind of the oppisite problem,my spring was not strong enought to return the slide, so my slide would stick wide open. suprised the hell out of me the first time i started the bike and it high rev'd on me. i put a new spring in it and have been good to go
and kids are awesame,i have 2 girls. they rock

[ID KX500]

Tether Kill Switch?   http://www.partsforatvs.com/default.asp?p=623&c=203&cn=Bars+%26+Controls
Sorry man,,,, Monday morning Quarterback here

[KXT500]

yea i know about tethers. it really was the 1st day that i had it running



well i found the problem. i have another 39mm pwk to reference so that helped. my pwk on the 3 wheeler had a PJ carb cap in it. no big deal right? well the throttle tube is smaller and it was catching on the top of the cable retainer. it sticks tight too!!! i put the other cap on and all is fine. i have to tore apart for paint and repair now.

[Friar-Tuck]

 Sorry to hear about the mis-hap..
  We were having a rash of throttles sticking on a 500 Honda site a few years ago.
 It seems the end of the sheathing on the cable pulls out of the top of the carb and hangs up and won't let the throttle close.
 Ooops... I see you've already got it. And yep the CR's used a PJ OEM.
  Tuck\o/

[k5abuser]

been there done that  . welcome to the club  . i hope you heal soon with no limpppppppping  . good luck in get back on three wheels

[KXcam22]

In the old days it was mandatory to lockwire the cable to the carb. If you wanted to live. Cam.