KDX220 Very Rich

Got questions? We got answers....
Post Reply
Pelton
Member
Posts: 4
Joined: 12:01 am May 08 2012
Country:

KDX220 Very Rich

Post by Pelton »

Having trouble with a KDX220 it is stock with the exception of a pro circuit platinum pipe.

It is very rich with lots of smoke and excessive spooge. It will only start with the throttle wide open when it is warm. All riding at sea level or close to it.

The jetting is already very lean at 140 on the main and 35 on the pilot. Needle is on the top clip. Bike runs ok, but no where near what it should. Moving the clip up and leaning out the air screw made it run better.

It has lots of compression, clean air filter, and a new plug. Doesn't burn gearbox oil so I dint think it is a crank seal.

Using yamalube at 32 or 40:1 and 94 octane gas.

Any ideas? I am stuck. I don't want to go much leaner on the jetting but it seems like that is what it needs.

Thanks for the help.
User avatar
scheckaet
KDXRider.net
KDXRider.net
Posts: 3740
Joined: 12:09 am Nov 10 2005
Country:
Location: edmond oklahoma

KDX220 Very Rich

Post by scheckaet »

http://www.kdxrider.net/forums/viewtopi ... 105&t=1156
check this again, seems you got it covered though.
when was the last top end done? Are you still running the stock piston?
Is your kips working? did it happen all of a sudden?
User avatar
Julien D
KDXRider.net
KDXRider.net
Posts: 5858
Joined: 07:53 pm Nov 07 2008
Country: USA
Contact:

KDX220 Very Rich

Post by Julien D »

Another bad jet block gasket, perhaps?

There's a rubber gasket/o-ring between the jet block and the carb body. If the carb is dipped or soaked in cleaner, this gasket deteriorates causing a persistent rich condition.

Just a thought....

Oh, and welcome to KDXRIDER!
Image
boghopper 250
Member
Posts: 14
Joined: 01:08 pm May 08 2012
Country:

Re: KDX220 Very Rich

Post by boghopper 250 »

Have you checked that the reeds are seating properly?
Pelton
Member
Posts: 4
Joined: 12:01 am May 08 2012
Country:

KDX220 Very Rich

Post by Pelton »

Not sure when the last top end was done or the piston. I will be doing a top end shortly as I am aware of the 220 piston issue. I'm just trying to get it running correctly first. The compression is good so I don't think the issue is related to the top end.

I read about the gasket issue and have already changed the o rings.

Not sure on how to check the reeds seating. I did a visual inspection on the reeds and held them to the light, could not see anything shining through. Is there anything else to check reeds or is that all that can be done?

Thanks for the suggestions guys. Really looking forward to getting this thing running as it should.
boghopper 250
Member
Posts: 14
Joined: 01:08 pm May 08 2012
Country:

Re: KDX220 Very Rich

Post by boghopper 250 »

As long as the reeds are touching the block all the way around... nice and tight with no gaps you should be ok. It sounds like you are fine there.
Pelton
Member
Posts: 4
Joined: 12:01 am May 08 2012
Country:

KDX220 Very Rich

Post by Pelton »

Any other ideas anyone?

Running out of things to check!
User avatar
Julien D
KDXRider.net
KDXRider.net
Posts: 5858
Joined: 07:53 pm Nov 07 2008
Country: USA
Contact:

KDX220 Very Rich

Post by Julien D »

When you say the compression is good, what exactly is it? Have you been able to test? Symptoms really sound like the jet block gasket. Double check that the jet block seated correctly when you replaced it?
Image
Pelton
Member
Posts: 4
Joined: 12:01 am May 08 2012
Country:

KDX220 Very Rich

Post by Pelton »

Compression test was 120-125ish.

I'll pull the carb and double check the jet block again.
User avatar
Julien D
KDXRider.net
KDXRider.net
Posts: 5858
Joined: 07:53 pm Nov 07 2008
Country: USA
Contact:

KDX220 Very Rich

Post by Julien D »

I had a 90 for a while, which ran similarly. We kept going smaller and smaller on the jets and never could get it right. Sounded about like yours. Several others with similar problems. I know you said you replaced it, was this what you replaced?
http://www.motorcyclecarbs.com/_P12161.cfm

J.
Image
Post Reply