38 pwk air striker jetting

josh · Post by **josh** » March 28th, 2012, 4:42 pm

hello fellow hoons. I'm sure this has been asked before, but i have an 01 sumo with:

oem pipe freshly sealed with high temp rtv
pro circuit silencer fresh packing
fresh cleaned stock air filter
stock reeds, 2 season old
4700ft altitude
38 pwk air striker jetting is: DGN 3rd position, 38 slow, 178 main, A.S is 1/2 turn out

my question is i have been fighting spooge on the flange, and out the tailpipe. does this jetting soung about right? starting fresh for the season, and i need some help in getting her running good.

thanks for looking, josh

johnnytheswede · Post by **johnnytheswede** » March 29th, 2012, 12:15 am

Hello Josh. What temp do you have where you live? The needle and the mainjet doesn't seem to match up really. On the other hand a rich main does not mean that you have spooge. how do you run your bike? At which throttle pos. are you mostly running? How is the bike behaving? Does it bludder a lot at light throttle? Does it run clean when you give light throttle? How does your plug look?

Johnny

josh · Post by **josh** » March 29th, 2012, 8:07 pm

my temperature is at 80 degrees. i made the switch from running in the sand to riding on the road a while back, and it seems to start spiting oil on the turn signal, out the tail pipe. i mostly ride from half to 3/4, and some wide open throttle. my dynoport seemed to hop the front tire rhythmically with the piston. just off idle seemed to hold back, other than that it seemed to run good. ran the plug 250 miles and didn't foul a plug. what would you recommend at 3200ft 80 degrees 40:1 oil mixture on a 38mm PWK air striker carburetor?

oh and it starts up just fine

thanks josh

johnnytheswede · Post by **johnnytheswede** » March 29th, 2012, 11:05 pm

Ok. How does the bike feel at light throttle? Do you have a cracking and bluddering sound or is it just a smooth hesitation? What slide is there in the carb?

Johnny

josh · Post by **josh** » March 29th, 2012, 11:36 pm

it seems more of a hesitation, it has a 6.0 slide. do you think 38 slow jet , 1/2 turn on the air screw is too lean of a slow jet? should i put a 40 slow 175 main? my mistake, my altitude is 4700ft

johnnytheswede · Post by **johnnytheswede** » March 30th, 2012, 4:58 am

Well,that could be the case. Try a 40 or 42 pilot and see. Maybe you should use a needle with less taper too. CGN for example. Then you lean it out a bit at 1/4 to 3/4 throttle.

Johnny

josh · Post by **josh** » March 30th, 2012, 10:56 am

thanks for the tips! will post results and report back

Post by **AlisoBob** » March 30th, 2012, 11:51 am

Keep going smaller on the pilot and raising the needle until it gets to the point where you whack the throttle, and it boggs. This is the turning point where you start richening it back up.

SOMETHING TO KEEP IN MIND:

As you lean it to improve the rideability mileage, your also cutting back on oil volume through the motor.

On a dirt bike, your using more throttle, at lower revs.... this increases oil flow through the motor.

On a dual sport / SM application, you use less throttle crusing around at higher revs... this decreases oil flow and lubrication to the motor.

If your coasting down hill, in gear, with the throttle closed... there is no oil entering the engine.....

If I had a street ridden CR500, I wouldnt use anything less than 32:1, maybe even 25:1.

josh · Post by **josh** » March 30th, 2012, 8:36 pm

thanks for the tips! i have been searching the past posts and getting more of an idea as to what to look for (the way its acting rich or lean)

how would you describe a rich condition?
how would you describe a lean condition?

its just been a while since i have ridden it. with it being put away for so long, i kinda forgot how it was acting before. I'm just about ready to ride it again, and start from square one, so I'm just getting ideas about what to look for and where.

thanks,josh

johnnytheswede · Post by **johnnytheswede** » March 31st, 2012, 8:03 am

Lean condition gives hesitation and a bwwoooaaaahh!
Bad response when you open up the throttle.

Rich condition gives a brrrrrrrrrrraaa! And some smoke:=)!

Yog got it:=)?

josh · Post by **josh** » March 31st, 2012, 12:27 pm

that does make sense, just needed someone else to say it! thanks

josh · Post by **josh** » April 6th, 2012, 6:22 pm

took the bike out today, i ended up changing to a 40 slow, 175 main, air screw 1 turn out and fouled a plug; cruising at light throttle then got on it and it just blubbered out and died. changed the plug, turned the screw out 1 1/2 and it started up. i really didn't notice much smoke at idle, should i be worried that i am too lean? do you think i should go to a 42 slow, and mix 32:1?

thanks for the ideas!

Post by **AlisoBob** » April 6th, 2012, 6:31 pm

Put a #168 main in...

josh · Post by **josh** » April 6th, 2012, 6:41 pm

so i should change to 168 main, 42 slow, DGN needle 3rd position, air screw 1 1/2, 32:1 mixture at 80 degrees ferinheight at 4700 ft. sound right?

thanks for all the help!

Post by **AlisoBob** » April 6th, 2012, 6:47 pm

Put in a #40 pilot if you have one.

Your baseline jetting is for sea level riding, your almost 5,000', and its warming up.

Lean the thing down.

BannedCR500Riders.com

38 pwk air striker jetting

38 pwk air striker jetting