Is a 38mm carb too big?

[craigz9876]

Not had my blaster long just stripped the carb it is a 38 mm keihin pwk. Not had a problem with jetting etc but checked the sizes whilst it was stripped I'm running a 68 and 170 jets. Does this sound alright? I'm running a vitos bbk ported, a DMC alien pipe, +4 timing mod and a high flow airbox with a k and n filter. I'm replacing the filter as I've heard bad reports about them. But does this sound right for my mods? Thanks Craig

 

[Blaner]

wow 38 is rather large! what sort of riding do you do?

 

[craigz9876]

Just normal Offroad riding, well little on/off road really. It's how I bought it so not sure what it has been setup for!

 

[craigz9876]

I'm thinking of putting in the +3 stroker when vitos get them back in stock, so would this still be too big then?

 

[BlasterAzores]

I'm thinking of putting in the +3 stroker when vitos get them back in stock, so would this still be too big then?

Thats just about the setup im using... 38mm pwk Keihin / +4mm hotrod Crank / Vforce3 / Tommey pipe with procircuit exaust ... No timing advance. No problem what so ever.

 

[craigz9876]

Nice1 so it should be bang on once I get the +3 and rejetted. Thanks for the reply

 

[Luni]

Jeez those jet sizes are HUGE for a Blaster.

I couldnt get my 36mm PWK to run right without jetting way the hell down. I was running a 32 pilot and a 110 main and was still too rich.

 

[craigz9876]

Once I finally get my piston I've ordered from vitos I'm gonna do a plug chop as it's totally as I bought it! It doesn't foul the plug tho!

 

[98blaster+4]

check for an airleak in the system, thats ridiculously big for such a mild motor
maybe its got some serious internal work your not aware of????

 

[craigz9876]

What would you class as serious internal work? I can't see any stuffer blocks on the piston or spacers on the block! My leak tester just come today so just waiting for my piston now

 

[98blaster+4]

well i would say that im pretty sure you can run a stroker crank with no visible signs of it on the outside of the engine. possibly a 240 sleeve. drag port maybe.

 

[CARNZ]

that seems like a lot of jet for such a small engine. I run a 38 PWK on my LT500R and I'm only at a 182 main and my engine is over 2x the size lol.

 

[con8quest6]

I've run a pwk 38 on my blaster and have had no probes. Your main jet sounds fine but the pilot sounds pretty rich. I don't think I've ever gone as high as 58

 

[Luni]

I dont understand how the hell you guys can get away with so much main jet on a 38 mil.

A 160 main is ALOT on ANY mil carb for a blaster without a 240 kit and a port. Im running a 140-145 on a 28 mil PWK.

 

[nd jat]

Not had my blaster long just stripped the carb it is a 38 mm keihin pwk. Not had a problem with jetting etc but checked the sizes whilst it was stripped I'm running a 68 and 170 jets. Does this sound alright? I'm running a vitos bbk ported, a DMC alien pipe, +4 timing mod and a high flow airbox with a k and n filter. I'm replacing the filter as I've heard bad reports about them. But does this sound right for my mods? Thanks Craig

He did mention vitos bbk ported, thou I'm not positive his idle jet isn't high even for that.

 

[BlasterAzores]

Im using my 38 carb, with a 162 main,
i ride at Sea level, 80% to 90% air moisture and 65ºF, all year round(average), i believe weather, altitude, temperature influences it a lot.

 

[craigz9876]

Azores what about your idle? I finally got my piston today so gonna rebuild in the morn. Once I'm run in gonna do a plug chop. My bottom end has always been very boggy but never floods the plug etc

 

[BlasterAzores]

a 42 pilot.
Honestly i think mine is still a bit rich on the 162main , my Blaster is missing something on the high revs, not "screaming" like it used to.

 

[BlasterAzores]

huuu... i was reassembling my carb back just now, and checking the needle/carbslide movement and realized that at full throttle the carb slide only goes like 3/4 of the way up, shouldn't it be going all the way up ?

 

[BlasterAzores]

nothing better then some pics !!

no throttle

full throttle

full throttle... shouldn't it be like this ?