Bogging down

[KDXhIllBillY]

Hey fellas.... just got my first KDX (kdx 220r 2003)
Seems like when I give it initial throttle it bogs
But when I double throttle it it opens up and pulls.
What’s going on
Ps.... I have put a fmf series 2 pipe on it
ALSO DOES ANYONE HAVE EXTRA PARTS

[kdxsully]

What do you mean “double throttle”

eBay has parts, check the for sale section here too

Sounds like you need to clean the carburetor, then if it still bogs, rejet.

[rungrandpa]

I would start adjusting your idle air screw. You may need to change the pilot jet. Read some jetting posts.

[bufftester]

That is a sure sign you need to clean and jet carbs, after you put in new plug, air filter, fresh fuel/oil, and make sure everything is mechanically sound.

[doakley]

Ditto on cleaning the carb as a first step. Then set the air screw to spec and see how she runs.
When I first got my new RB OEM style carb I had a bad big just off idle. A little playing with the air screw solved the problem.

[KDXhIllBillY]

Thanks for all the help fellas. Just found out the guy I got it from had it sitting in garage for a year at least. It runs and cranks right up but it won’t idle and “double throttle” means getting into it little bit backing off and gassing it again quickly ( hillbilly lango)
Fixing to pull it apart. Carb clean,etc... might even do a ring job on it since it’s beginning of riding season. I’ll repost after the TLC job for others in the future

PS don’t ya love how EVERY 2 stroke for sale online “has a fresh top end” only 4 hrs on fresh top end rebuild....

[kdxsully]

Gotta love it.

[doakley]

I can’t believe nobody has told him to check the piston yet to make certain it is NOT OEM. We’re getting slow!

[kdxdazz]

I can’t believe nobody has told him to check the piston yet to make certain it is NOT OEM. We’re getting slow!

That sentence gets repeated a lot but it's a 2003 model. Find it hard to believe that kawasaki made such a great bike for all these years but just kept using a defective piston. Something doesn't ring true

[KDXGarage]

DO NOT dip the carb in Berryman's or similar! You will damage the hidden jet block gasket. About $20 now and an odd-ball security Torx T-20 to get the jet block off.

[SS109]

I can’t believe nobody has told him to check the piston yet to make certain it is NOT OEM. We’re getting slow!

That sentence gets repeated a lot but it's a 2003 model. Find it hard to believe that kawasaki made such a great bike for all these years but just kept using a defective piston. Something doesn't ring true

Well, that's because it is true. It is a well known defect of production 220 KDX pistons. Some pistons would last for years, some for mere hours, but all of them, when they eventually do fail, send shrapnel through your engine. Just search the forums here and online and you'll see all the times when the factory 220 piston came apart over the whole production run of the 220. They used the same piston from the start in 1997 to the end in 2005. Smart thing is always check to see if the stock one is in there, and if so, immediately replace it.

[kdxdazz]

I can’t believe nobody has told him to check the piston yet to make certain it is NOT OEM. We’re getting slow!

That sentence gets repeated a lot but it's a 2003 model. Find it hard to believe that kawasaki made such a great bike for all these years but just kept using a defective piston. Something doesn't ring true

Well, that's because it is true. It is a well known defect of production 220 KDX pistons. Some pistons would last for years, some for mere hours, but all of them, when they eventually do fail, send shrapnel through your engine. Just search the forums here and online and you'll see all the times when the factory 220 piston came apart over the whole production run of the 220. They used the same piston from the start in 1997 to the end in 2005. Smart thing is always check to see if the stock one is in there, and if so, immediately replace it.

Agreed you can find lots of stories about that, you will also find just as many stories about guys running 60 70 80:1 oil ratio, did the kawasaki engineers really get the piston wrong and the oil ratios wrong. Not saying what your saying is incorrect but something doesn't add up

[doakley]

Not worth the risk to me. When I bought my 220 I was unaware of the piston question. Still I pulled the jug and installed a new Wiesco piston/rings/etc. I just wanted to KNOW what was in there. It was only later that I learned of the stock question.