OKO 30mm start point

[TIM LUTZ]

Just ordered my OKO 30mm flat slide (PWK clones) and was wondering a good start point for jetting.

I'm at about 1000 feet and run 93 pump gas and 40:1 Klotz thru a stock stroke Shee with DMC 916 exhaust. Cut airbox lid with a uni. Ported stock cages with dual stage reeds. +4 timing. The jugs have a nice dune/MX port job (+1.5mm on the polished exhaust and +1mm on the transfers & very open intakes) Running stock head but looking to get a cool head with 20cc domes.

 

Any input would be great.

Edited July 29, 2010 by TIM LUTZ

[bigborebanshee]

Just ordered my OKO 30mm flat slide (PWK clones) and was wondering a good start point for jetting.

I'm at about 1000 feet and run 93 pump gas and 40:1 Klotz thru a stock stroke Shee with DMC 916 exhaust. Cut airbox lid with a uni. Ported stock cages with dual stage reeds. +4 timing. The jugs have a nice dune/MX port job (+1.5mm on the polished exhaust and +1mm on the transfers & very open intakes) Running stock head but looking to get a cool head with 20cc domes.

 

Any input would be great.

 

I just ran the identical setup.Start with 52 pilots needle at middle clip and 152-155 main..airscrews 1.25-1.5 out

 

A 50 pilot will work too,just make note of how many turns out you are on the screws.It was ok with a 50 during june,july and aug.Started to get finicky in sept ,oct months though.

Edited July 29, 2010 by bigborebanshee

[TIM LUTZ]

Thanks for the info. Anyone else running the 30mm OKO or Keihin PWK30's

Thanks

[sleeper06]

i SET UP A CUSTOMERS BIKE with these carbs,he had an aggressive port job,19 cc domes,vf3s,pro-circiuts,I ended up at 140 mains,55 pilot.These carbs liked big pilots.This is also a bike that I did a staggered port map,The bottom end is unbeleivable.I think I was at 188 on the exhaust side.I did have a problem getting them 100% the way I like it.He ended up putting 33pwks on and problems stopped I dont think the carb gave enouph fuel at full throttle

[RadarRacing]

Exactly what they said. I usually have to lean the needle to the top or one off the top. 52 pilot as they usually. Come with 39s. Then since your trans is raised 1mm I think close to a 145/148 main.

They are prone to running bowls dry. I drill the seat out larger. .

[jharader]

Major issues with bowls running dry... i drilled out fuel inlet holes, did not help.... set floats where it was on verdge of overflow and worked out fine... do yourslef a favor and check the float height before you install, mine werent even and the factory setting did not hold enough fuel in the bowls, this can make for a SERIOUS headache trying to adjust and not to mention burn up your motor.. some people were able to bolt on and go, not the case with me and several others..

[TIM LUTZ]

I have heard a lot about the small fuel passage on the 28 and 30 OKOs and was planning on drilling them out. Wonder if I should go ahead and machine some 1/4" bowl spacers.

[shelrad1]

I just got in some 30mm OKO's today. It was a son of a biscuit getting the stock boots over them! Mine came with 160 mains, but I have more engine mods ( was running 350 mains in the stock carbs). Had to bend the clutch arm down so the left one would clear. The right one rubs the clutch cable/cable holder, but I think it will be ok. Wont get to see how it runs till tomorrow, as I need a little more fule line.

[TIM LUTZ]

I just got in some 30mm OKO's today. It was a son of a biscuit getting the stock boots over them! Mine came with 160 mains, but I have more engine mods ( was running 350 mains in the stock carbs). Had to bend the clutch arm down so the left one would clear. The right one rubs the clutch cable/cable holder, but I think it will be ok. Wont get to see how it runs till tomorrow, as I need a little more fule line.

So how does it run? What jets did you end up with?

[shelrad1]

So how does it run? What jets did you end up with?

 

 

Sorry for the delay, its been so hot out I havnt been fooling with much of anything thats outdoors. Yesterday I did a throttle chop and ended up going up to 165's. The plugs look good, but I would still like to try 170's, dont have any yet. Air screws are 1-1/2 turns out. Dont remember what slow jets are in it - whatever came with the carbs. The bike is running better than it has in years, have been putting up with sloppy/junky stock carbs for waaaaaay too long !!

[TIM LUTZ]

Update,

 

The used OKO 30s I bought off Ebay ($110) came with 150 mains, 50 pilots, powerjets & chrome slides. With reed spacers they clear the clutch arm just fine. Tip of the day on the airbox boots. Stretch over a 1 1/4" pvc pipe and toss in a pot of boiling water for 10 minutes.

 

The jetting seems really close for my mods. I'm at 1 turn out on the air screws so may need to go to 52 pilots. Only loss in bottom end I can tell is right off idle and that is probably the pilots. They do flat out scream on the top end. So much I now need a lock up.