What main and pilot should I run?

[wwholden]

I already asked this question but didn't get any numbers. Im going to buy jets tomorrow and dont want to end up buying all the wrong sizes. I will be buying an assortment but I just want to make sure Im in the correct range.

Shear Head Pipe w/ FMF Turbine Core 2 Silencer
Boyesen Power Reads
33mm PWK Carb
Clamp on Carb K&N Air Filter
Stock Porting

The carb currently has a 140 main and a 48 pilot. It takes several kicks and me choking it with my hand to get it running. Once running it has absolutely no power. I have to rev it out and feather the clutch to get it moving. Doesn't ever hit power band and can barley propel itself in 4-6 gear.

Any ideas what numbers I should be running???? Replies are greatly appreciated!!!

 

[Wifesblaster]

I replied to your other post

 

[wwholden]

Yeah I saw but we have different mods. Also I researched Mikuni to Keihin jet conversion and found a chart. A stock blaster runs a Muniki 220 right? The conversion charts dont go up to a 220 though??? But my Keihin 140 convers to a Mikuni 122.5. Seems a lot smaller than a 220 that would be on a stock blaster. Shouldnt the more mods the large the main should be?

 

[Wifesblaster]

I just took a 28mm pe carb off of mine. It had a 125 main. I cant remember what pilot. I want to say 40. It seemed to run pretty good.

 

[Wifesblaster]

What carb do you have/using? You list of mods says 33mm and your sig says 28mm.

 

[wwholden]

Its a 33mm PWK. This is for my new bike.

 

[Wifesblaster]

http://www.blasterforum.com/engine-13/33mm-carb-these-specs-36412/



This has some good info on it

 

[Wifesblaster]

http://www.blasterforum.com/engine-13/33mm-carb-these-specs-36412/



This has some good info on it

 

[wwholden]

Yeah I read it. Still doesn't give me any general numbers though...

 

[Wifesblaster]

Well i THINK most people with a ported cylinder and pipe run between 150 and 160 on the main. Try a 50 pilot. Not 100% though. Hopefully somebody that runs this carb will chime in.

 

[Larry's Shee]

http://www.blasterforum.com/engine-13/what-jets-you-using-28981/
http://www.blasterforum.com/jetting-139/jetting-numbers-solution-17259/
Might find something in either of these. Might not find exact same but close. At that point you make a educated choice and start rich/fat and work your way down from there. You educate yourself by reading threads , if someone doesn't give you a start point. Loose rule of thumb you can use is Mikuni main numbers are 2X a Kehien, pilots are 1/2, so even if someone runs a different brand, but simular otherwise you'll get a good idea where to start.

 

[wwholden]

Ok thanks fro the links I totally forgot about those threads. So I gather that simliar mods have pilots around 50 and mains around 150.

So heres my selection Im going to pick up today:
Mains: 155, 152, 150, 148, 145, 140, 138, 135
Pilots: 55, 52, 50, 48, 45, 42, 40

Ill post back once I get this all figured out.

 

[wwholden]

I went to a dealer and they said to try a smaller carb first. So I put a 28mm PE carb on the blaster and got it running with a 148 main. Has amazing top end but very weak bottom. It is impossible to start though without holding you hand over the carb to fully choke it. The little choke on the carb just isnt good enough. Its got a 50 pilot in it now but I think its lean. Im ruuning a clamp on pod filter on this carb also. Engine seems to run best with mixture screw screwed all the way in with no air filter installed or a couple of turns out with a air filter installed. Keep in mind that its still the clamp on filter. Anyone else think I need to go to a bigger pilot?

 

[wwholden]

Bump! Bump! Bump!

 

[boomadge]

I know you said it seems great on the top end but, 148 seems a bit small imo
for a pod filter setup. If it were me with your setup and I am going on your elevation in ohio being 500-1000 ft ASL. 55 pilot and 160 main should be darn close.

 

[wwholden]

Im not real certain that the 148 is right either. I tried 140, 145, 150 with plug checks. I performed the plug checks by starting it then immediately WOT up through 6th gear then pulled the clutch and killed the engine. I have a pic of each plug for each pull. I really cant see a diference between them. Plus the brown is only on one side of the plug nothing like the ring Ive seen with other members pics.

140 main:

145 main:

150 main:

 

[Wifesblaster]

You have to cut the threads off to see the smoke ring.

 

[wwholden]

I couldn't figure out how to cut the threads off. Tried using a cordless drill and hack saw but it just wanted to slide away using the path of the threads. I can see down in there and it looks all white except for one side at the tip.

 

[wwholden]

Bump! Bump! Bump!
Going to dealer in a bit and would like a few more comments on the 55 pilot and 160 main.

 

[Awk08]

i'd get pilots in the mid/high 40's up to a 60
mains ....high 140's - 160's

the setting of the airscrew that it idles the highest tells you if that pilot is correct
under 1/2 turns out for highest idle = larger pilot
over 2-1/2 turns out = smaller pilot

the needle seems to be the key to these A/M carbs
a call to Carburetor Parts Warehouse will get you straight on that, know your current needle size if you call

you have to hold the plug in a vice and cut with the hacksaw, rotate as needed