KDXRIDER.NET

I blew a hole in my piston so was forced to rebuild the top end. It never ticked over in the first place but I would like it to now. Any suggestions welcome, I'm not bad with a set of spanners and am willing to take the carb apart, just no idea which bits to bend or tweak.

The best I have had so far is an idle around 3-4k rpm but then it just dies if I don't keep the revs on.

Would you write it in proper English plz?

Seriously, I'm not sure what u meant by: "never ticked over in the first place but I would like it to now"
I assume you're talking about carb jetting, more info would be useful to help u out: what model/year bike u have, mods, altitude...
If you having carb issue, this is a good start:
http://www.kdxrider.net/forums/viewtopic.php?t=1156

Also, why did you blew a hole in the piston?
(I have the feeling you have a 220...)

It may have been a 220 but after the blow hole, I have had the barrel put back to the original size and I a now running the stock piston. The bike would not idle when i bought it. I assume the blow hole was because the fuel mix was to lean.

It is a 1988 model, not sure of altitude, i live in worksop, uk if you coulp help me with that?

I believe correct jetting could solve my problem.

Help is very welcome in any form.

Thanks.

This section is reserved for Ron Black carb and head mods. Moving to general.

Thanks.

juliend wrote:This section is reserved for Ron Black carb and head mods. Moving to general.

Thanks.

What does this mean??? Sorry i'm new on here

Ron Black does carb mods and head work to bikes. The section you first posted in was for his work.

The general section is more for general questions, like yours.

Could you please explain "ticked over" and it will probably help alot.

English "ticked over" = "ran" in American english.

I think your carb is plugged, most likely pilot jet.
Pull that carb apart and clean the sucker out.

I will have a look at that this evening and let you guys know the result.

Thanks

I got round to doing it a bit earlier than I thought

Fletch, you are an absoloute star. The pilot jet had a bit of crap in it. I have stripped the carb apart and cleaned all the jets and returned the jet needle back to the 2nd position as it was on 3rd for some reason.

For 3months I have had this problem and finally, solved with 15minutes work and advice from some good people.

Tick over means engine idle (Sorry for the mis-understanding)

I am now able to warm the bike up at 1-2krpm and not 3-4



Cheers Fletch

Your welcome.
your thanks to this site is well deserved, I have learned tons here too.

I'm wondering what can cause an engine to melt a hole in a piston???
You may want to check that engine for crank seal leaks or other leaks elsewear. Pull the l-side mag cover and look for oily resedue on the bottom of the flywheel.

Generally a lean condition. So yeah, an air leak or horribly incorrect jetting.

There ya go confirmed by a more knowledgeable mind; check for air leaks!

Sorry guys, I think I spoke too soon. Took the bike out for a spin after cleaning the carb etc and it bogs at low revs and won't idle when the engine is warm.

how far is your idle screw in?
Mine revs really high when cold then goes back down when at running temp...

still haven't told us what's your jetting and mods you are running...

No engine mods at all. Only mod is a swing arm conversion. I will get the jet needle out tomorrow and see what it says on it. I hate carbs :-)

pilot and main #?
How many turns on the air screw?

scheckaet wrote:pilot and main #?
How many turns on the air screw?

I have the bike running at 1.5 turns on the air screw. Aparently any more than 2 turns can damage the engine?

I will keep you posted maybe mid-day saturday (GMT) with the jet sizes, a bit too busy at work today to be taking the carb off again and I will no doubt be out for a beer tonight being as it's friday

Speak to you all again very soon and big thanks well deserved up to yet

Mart56966 wrote:

scheckaet wrote:pilot and main #?
How many turns on the air screw?

I have the bike running at 1.5 turns on the air screw. Aparently any more than 2 turns can damage the engine?

That's inaccurate. From what I recall of carbs you can run up to 2.5 turns or so out. Even with more than that it won't hurt anything, it's just recommended to swap to a different pilot jet for better tunability after 2-2.5 turns.