New guy on the block

[BlackMist]

Hey all, I'm Colin just picked up a 2002 kdx220 from the original owner. It's completely stock for now and I'm just going through everything to get it up to my standards of OCD haha.

I was going through all the receipts he provided and it appears he put a 140 main jet in. I'm in Calgary Alberta so majority of riding is McLean creek which Ive read is 1486m (4875'). Does a 140 jet sound right for that? I've gone up 2 points on the jet size for my gf's bike and noticed tremendous gains so I'm worried 140 main may be to lean for the KDX.
From what I've read most guys around the 3300' go up not down on both main and pilot with adjustments to the needle clip and fuel screw. Anyone in the same altitude have some magic numbers? I'll be riding a lot harder than the guy I bought it from.

I'm hoping that the small main jet and bad fuel are to blame for lack of low down power as I'm not really feelin a KIPS cleaning yet.

Thanks! Hope to be an active member!

 

[BlackMist]

Just remembered the other question which I could not find the answer to, the previous owner was running 32:1, I was wondering if it would be safe to switch to 40:1

What is the stand point on amsoil? I got A bottle of hp injector from my co worker

 

[KDXROCKET14]

Hello, congrats on getting a kdx 220..im sure you will end up really loving the bike..on the jetting, the honest truth on if your main is too lean or rich etc, is for you to read your plug..going off of what others run will get you no where..maybe a good baseline but everyones jetting can be different..the elevation, temp, air density, humidity, all effect it ,and then you have people with different exhausts, reeds, etc..so get a good reading on your spark plug.you can experiment with jets after you know it isnt lean..then pop in a few main jets up and down from 140 and see what feels best.and make sure it is a 140 for sure.a 140 is what i ran for that elevation when i had a 33mm carb on my 220..now i run a 35 mm carb though..and lack of power down low wouldnt be your main jet, you will be lookin at your pilot jet for that.if it's stock which is a 42 pilot, you can definately run a 40 pilot. as a bone stock bike, i highly reccomend getting a fmf gnarly pipe for it..then the power on top and down low will start pouring on!! mods on the bike can go on forever but stock kdx pipes are way too restrictive..fuel mixture, 40/1 should work fine..i run my 220 at 52/1 with golden spectro and love it..if you have any questions just reply on back,
Ryan

 

[BlackMist]

Thanks for the wisdom, I'm just starting to get the hang of tuning carbs. With my boat it was always up up up as the engine was a hungry beast so I'm baffled by going down

I've been messing around with the girlfriends TTR and I've gone up on the main jet and pilot, feels like I'll have to go down on the pilot but after the main was done it would haul my ass up some steep grades with out hesitation s before it wouldn't get me up unless I was wot in 1st. Sounds like I'll be buying a few jets, atmospheric pressures here change daily...
As for the bottom end, what kind of symptoms are to be expected if the kips is gummed up? Are they distinguishable from an incorrect pilot jet?

 

[ridejunky]

gummed up kips will affect top end unless the sub ports are stuck"open" which is usually not the case( there is a real good write up on kips you can access off the home page.) if it is not optimal down low it is probably jetting. remember if you change oil ratio to 40:1 you have richened up the F/A. ratio not lessened it.