03 yz125- blues

[Mr.BeRm]

Phase 1-

Hi guys. I recently purchased a 03 yz125. I have a problem with it though. It runs great on flat ground, but when I jump, and I'm decending out of the air towards the ground, and on impact, it bogs down and wants to die. I have to immediatly get back on the gas and peg her, because it seems to clear her out. I was wondering what the problem could be? Something with the carb, I'm sure. I'm planning to leave tommorrow for the track, so you guys reply fast Thanks.


Phase 2- Ok... I took the carb off, cleaned it, and found nothing out of the ordinary. It still bogs in the air.. and it also sounds like it's flooding over when I whisk the throttle quickly on and off. Almost like it's running a very rich mixture (blue smoke is steaming out of it.) My float bowl looked good, nothing wrong there. My carb settings seem perfectly fit for the weather, but it's running like this? The vent tubes are also clean. Also, I'm getting the gook out of the silencer. The gas is new.. everything. I was thinking maybe an airleak, but this wouldn't that cause a lean mixture? One more thing.. after I reassembled the carb, the idle screw has no effect ON the idle. Whats up with that? Seems I reassembled everthing correctly.


Any advice? Thanks.

 

[whyz]

Adjust float level, :think:
and you are big time on the rich side IMO.

and when you land,you should be on the gas.

 

[whyz]

whoops forgot ,,

Look on the left of the screen and Look up Eric Gorr's website,
Alot of info on jetting.

Man I'm all mixed up :think:

 

[whyz]

This one ,,Sorry..http://ericgorr.com/twostktech/twostroketech.html

 

[Roost165]

I read a tech article in a moto-mag. I guess this is a big problem for some people. One solutiong was to put a piece of foam rubber under the carb so it doesn't hit the case and cause the fuel to get splashed.

 

[Mr.BeRm]

Well I can't exactly be on the gas until it's about 30 feet from where I landed, all the space before that is just bogs until it builds steam to whine out again. Thanks for the info.

 

[96717]

Originally posted by Mr.BeRm

(blue smoke is steaming out of it.)


Any advice? Thanks.

isnt that something to do with burning the gear oil?? leaking gasket?? idk though your bike is brand new!

 

[whyz]

Originally posted by Mr.BeRm
Well I can't exactly be on the gas until it's about 30 feet from where I landed, all the space before that is just bogs until it builds steam to whine out again. Thanks for the info.

You need to be on the gas before you land,it will also help help your suspension to work for you when you give it gas.
But anyway,what do I know I ride a 4 stroke. :laugh:
Here's more info for ya.
http://www.dirtrider.net/forums3/showthread.php?threadid=60392&highlight=need+jetting+help+fast
And another link on jetting which is alot easier to understand. http://www.ecmx.com/bike_tips/jetting.html
And here's the whole link with alot more of tech stuff.
http://www.motosports-boise.com/rmd/tech.htm
And also if you really want good expert advice,
Mr. Rich Rohrich is the Go To Guy. :laugh:

 

[Mr.BeRm]

Well I've been riding a long time. I'm positive I'm keeping it pinned... No matter how I land, gas on, gas off, blah blah.. It will still bog. The jumps I'm hitting are 4th gear. W.O.T. If I hit a jump at a lesser speed, the problem isn't as bad. It's mainly just sudden kickers and such.

 

[whyz]

Originally posted by Mr.BeRm
. No matter how I land, gas on, gas off, blah blah.. It will still bog.

Have you tried the jetting scene? :silly:
I didn't mean to imply that you couldn't ride. Sorry.

How's the throttle response off idle?

 

[Mr.BeRm]

Yes, I looked over the links. My bike runs poorly at 1/4 - 1/2 throttle. This would apply to jet needle and clip position. So I moved the clip up one notch, to lean it out. ( Was at position #3 ) Now it seems to suffer from extreme richness. Oil is still running from the silencer, and it fouled the spark-plug. Basically I couldn't get W.O.T because of all the bogging. This should have leaned the mixture.. but it made the mixture seem even richer. I've been trying different settings with pilot, air, and even main jet. None have been sufficient. And again- what could be the reason for my idle screw having no effect on my idle, no matter how far in, or out I turn it? Thanks again guys, this problem of mine seems fairly confusing, all help is extremly appreciated. :-)

 

[Mr.BeRm]

Also, I can't say how it is off idle- mainly because I have no idle. lol. But, it seems a bit burbly. I messed with the air and pilot jets, no effects.

 

[marcusgunby]

It sounds like the float level is too high.

 

[Mr.BeRm]

Well I've limited it to basically one option. The pilot jet. The main jet is fine, the bike is awsome up top, the main needle is good too, mid range is sweet. The low end isn't as great when the bikes isn't W.O.T for over a few seconds. So I'll drop the pilot one and see what happens. :)