What happened???

[scspencer]

I was riding today and my bike was feeling a bit boggy, I though it was just that the bike was not warmed up yet. After about 5-10 minutes of cruising around the biek was still bogging out badly and smoking a ton. It was going just fine when i would pin it but it felt horrible 1/2-3/4 throttle. So when I get home i pull the carb apart. Everything looked fine until I came across the needle. The clip that was in the top position was now in the bottem position and the clip was REALLY bent. What could have caused this?? Also I am going to get a new needle and clip tomarrow and was wondering what is the best needle to get, it currently had a n3cj needle in it.

2002 yz250

168 main

45 pilot

5000-6000 feet

50-60 degrees

40:1 ratio

THANKS!!

[scspencer]

bump.

[paccorti]

Wow. I've never heard of anything like that. Any chance that the clip was not fully on and that's what caused the slippage and subsequent bending? What I can't understand is how the needle got bent. I wouldn't think that the throttle spring is strong enough to bend the needle. I can't really see how opening the throttle can bend a needle. How badly was it bent?

It's a mystery!

Peter

[scspencer]

it was bent pretty bad it looked like it was just pushed from the top position to the bottem clip and all the little fins on the clip were bent upward

[scspencer]

the needle will wear where the clip sits over time.not uncommon.

That is the reply eddie on the jetting fourm left me, I still dont get it.

[rusky]

weird... the 250 carb isnt dual cable so there couldnt have been that much pressure put on the needle to make is bend. Only 2 things i can think of.

1. You snapped your throttle a couple of times which loosened the e-clip and then slammed the needle up and down a couple of times.

2. A really awkward crash or hard landing.

[scspencer]

Rusky the needle itselt didnt bend just the clip.

[Agitator]

Maybe a piece of something jammed the needle/slide assembly in such a way that it couldn't return to idle, then some rough throttle chopping (resulting in momentum of slide/spring downward) slammed against the blockage and forced the needle to slip positions on teh clip.

Sounds far fetched to me and I wrote it

I'm glad it wasn't something more serious ?

[scspencer]

yeah me too haha. Im just puzzled how the clip could move down 3 positions by itself and bend like it did.

[RCannon]

The clip is almost held captive by that horrible little 6mm thing that holds the cable, right???

I suppose a damaged clip could get dislodged and end up in a different position......

I had a pilot jet completly fall out once.

[scspencer]

what did the bike do when your pilot fell out ?

[hallsy]

Did you have the carb apart prior to your last ride?

[Agitator]

the big plug in my mikuni fell right out. Even with gas pouring everywhere, the engine was revving fine. Took me a while to know that it was gone (wouldn't idle well). Luckily the plug was right on the back of the case just laying there. I'm glad I didn't finish warming the bike and ride somewhere- woulda' lost it for good

[scspencer]

yeah i pulled the carb and cleaned out the jets

[Agitator]

something probably got sketchy when you put things back. Did you mess with the throttle cable lock/spring/needle at all?

[hallsy]

Well sometimes when I put my slide back into the carb the needle doesn't line up just right with the needle jet and won't fall into place untill I get it lined up. I was thinking if that happened to you and you tried to force it in it could have pushed the needle up from clip 1 to clip 5 and bent the clip in the process. Is that possible?

[RCannon]

what did the bike do when your pilot fell out ?

Obviously it was my fault. I used a screwdriver that was just slightly too fat to change the pilot. It felt tight....

I had been riding most of the afternoon. Bike was jetted perfectly. Towards the end of the day low speed throttle response felt strange. Sometimes good, sometimes really bad. Finally it stayed really bad.

I thought for sure a big piece of dirt was in the carb. LOL

When I removed the drain plug , I saw my piece of dirt

All in all it was a great learning experience. It showed me just where the pilot jet range was.

[scspencer]

RC what kind of needles do you run in your yz250s ?

[scspencer]

Well sometimes when I put my slide back into the carb the needle doesn't line up just right with the needle jet and won't fall into place untill I get it lined up. I was thinking if that happened to you and you tried to force it in it could have pushed the needle up from clip 1 to clip 5 and bent the clip in the process. Is that possible?

no it went in there pretty smooth. (thats what she said I know)