starting point , pwk's

[woodro77]

hey guys , i bought the oko copy of the 28pwk's bored out to 30mm , bought them when it was cold, came prejetted (supposedly ) came with 155 main 52 pilot in the carb ,needle in middle, came with extra jets 160 , 150 ,mains and 50 pilot , 30 degrees outside and it ran good , rode it again at 42 degrees outside and it ran good but had a little bog just off idle , now its getting warmer out and i just want to know what you guys think is a good base line jetting to start with , i had fatty pipes but now changing to toomey t-5 's ,what do you guys think.

 

my mods are k+n no lid , toomey t-5's , slight port (trail port nothing crazy) +4 timing advance , v-force 3's , compression 140 psi ,

 

im at sealevel .

 

i know i have to do a plug chop but i have no where near my house to run it ,

 

took the fmf fattys off to put on t-5's and noticed a little puddle of oil in the flange of pipe , is this a sign of being rich ,

 

thanks for any help guys

[locogato11283]

id say that pilot is way too big. in every PWK carb ive run (33, 35 and 39) ive always run either a 42, 45 or 48 pilot, with 45 being the most common.. i think you need to drop that pilot down to at least a 48, maybe 45. as for the mains, you wont really know until you do a WOT plug test..

 

if you have oil in the pipes, especially a puddle youre rich..its prolly from idling and the pilot being too big.. what oil/fuel mix are you using?

[woodro77]

32-1 , why would they send that big of a pilot ? it would idle ok , if it was 3-4 sizes too big you think it would have trouble idling right ?

[Banchetta]

It might work now for the idling since its so cold out, but you'll most likely notice that it'll start hard and not idle once the weather warms up....I agree w/ loco...42-48 pilot range.....Your mains should be around the 155-162 range....Oil in the exhaust tips mean nothing...Its 30 degrees out...if your not fully on it, your exhaust temps will be low and the oil won't burn completely..I wouldn't go by that.

[woodro77]

It might work now for the idling since its so cold out, but you'll most likely notice that it'll start hard and not idle once the weather warms up....I agree w/ loco...42-48 pilot range.....Your mains should be around the 155-162 range....Oil in the exhaust tips mean nothing...Its 30 degrees out...if your not fully on it, your exhaust temps will be low and the oil won't burn completely..I wouldn't go by that.

 

 

i going to buy some more pilot jets , i going to try the 150 main and 50 pilot tonight ,

[jmd0346]

Im running a 52 pilot, needle in the third clip and 180 mains. Also at or near sea level. It still feels a little rich on the main and not quite right on the air screw. I just havent had time to work on it lately. It stilll runs like hell. Just not in its "dialed in" state yet.

 

 

 

Question for ya Woodrow. Does your engine seem to turn up faster now than with the old carbs? When I used to shift it had(Although short) more of a build up of power. Now as soon as the power band hits its time to shift! I guess this is just the cylinders filling quicker??

[woodro77]

Im running a 52 pilot, needle in the third clip and 180 mains. Also at or near sea level. It still feels a little rich on the main and not quite right on the air screw. I just havent had time to work on it lately. It stilll runs like hell. Just not in its "dialed in" state yet.

Question for ya Woodrow. Does your engine seem to turn up faster now than with the old carbs? When I used to shift it had(Although short) more of a build up of power. Now as soon as the power band hits its time to shift! I guess this is just the cylinders filling quicker??

 

 

yes it seems like the power band is shorter (hard to describe ) with the stock carbs it felt like they pulled a little longer , with the 30mm's it feels falls off the pipe a little faster ,

 

im not complaining though , they definitely make more power , with stock carbs when i race my brother ( trx 450 , pipe , cam , k+n , ) it s fast , he would beat me by a bike length with my stock carbs , but with the new carbs i beat him by a bike length , so im happy , i still think its not dailed in perfect . has a small bog at 1/4 throttle

[jmd0346]

yes it seems like the power band is shorter (hard to describe ) with the stock carbs it felt like they pulled a little longer , with the 30mm's it feels falls off the pipe a little faster ,

 

im not complaining though , they definitely make more power , with stock carbs when i race my brother ( trx 450 , pipe , cam , k+n , ) it s fast , he would beat me by a bike length with my stock carbs , but with the new carbs i beat him by a bike length , so im happy , i still think its not dailed in perfect . has a small bog at 1/4 throttle

 

 

 

 

Yeah thats exactly how mine feels. Not sure if its faster yet though. Mine also has a bog at 1/4 throttle. Maybe sunday I can tinker with it some.

[woodro77]

Yeah thats exactly how mine feels. Not sure if its faster yet though. Mine also has a bog at 1/4 throttle. Maybe sunday I can tinker with it some.

 

so did mine , i went from 52 pilot , 155 main , ,, today i put a 50 , 152 main air screw 1 1/2 out and it seemed to run better , idled a little better and rev-ed crisper , the bod just after idle is gone . im going to ride saturday and let you know how it works out .

 

they say these carb are set up for your mods but from what i have seen from everybody that has them got the same jetting , 150 , 155 , 160 ,52 , 50 , some people even had strokers and drag ported and got the same jetting as me,

[burleybanshee]

Hey Woodro77. How was the ride and did you get it dialed in? Going to be running similar set up but with a 4mil and was wondering what you settled in at on the pwk's.

[Banchetta]

Hey Woodro77. How was the ride and did you get it dialed in? Going to be running similar set up but with a 4mil and was wondering what you settled in at on the pwk's.

A 4 mill will pump a lot more air..If your running a mx or dune port, then I'd suggest a 35pwk carb. 162 mains, 42 pilot, DEK needle.

[woodro77]

i went with 152 main 50 pilot and air screw 1 1/2 turns out , it pull strong but runs like shit at lower rpm's when it gets warm , ran fine in beginning of ride , after 10 minutes it stated bogging and bubbling at just after idle , let it cool down and it was fine again untill it warmed up and it did it again .now im stumped ::

[Banchetta]

i went with 152 main 50 pilot and air screw 1 1/2 turns out , it pull strong but runs like shit at lower rpm's when it gets warm , ran fine in beginning of ride , after 10 minutes it stated bogging and bubbling at just after idle , let it cool down and it was fine again untill it warmed up and it did it again .now im stumped ::

Try lowering the needle. Your too rich on either the pilot or needle height...If the needle doesn't do it, then lower the pilot some more...Warmer weather will make you run too rich....we told you.

[woodro77]

Try lowering the needle. Your too rich on either the pilot or needle height...If the needle doesn't do it, then lower the pilot some more...Warmer weather will make you run too rich....we told you.

 

 

i called carb parts warehouse (where i got the carbs from) and they told me the same thing ,

 

it was in the middle clip i went 1 clip up towards the blunt end , started it and it seemed to run fine but i didnt ride it yet , the next day or so i will try it out ,