GNeed some base numbers for my jetting!

[wwholden]

So im trying to figure out this new blaster I got. Same one in my "Stroker Questions" thread. (Turns out not to be a stroker...) I got it because it had a no spark issue. Guy (didnt know crap about the blaster) said it would run great once that was fixed. Turns out that it had a lightened flywheel that fell apart. So I had a stock one laying around that I threw on it. Got spark now! But guess what... runs like sh*t. Its got a 33mm PWK carb on it with a clamp on K&N filter directly to the carb. Heres the problem. Has no bottom end at all once I get it running after 20 kicks, you have to rev the sh*t out of it and pop the clutch. Every once in a while I can feel it hit a weak power band. Nothing at WOT, seems to bog out. After driving it around the yard once the air filter would be leaking fuel out of it. I take the filter off and rev the engine and I get gas/air mixture flying out the carb. Idling I can watch the a light flow of fuel leak out the back end of the carb (air filter off). Seems like its too rich but this is my first time jetting a two stroke. Ive done 4 strokes before so I know the concept. Just not sure if a two stroke shoots a lot of excess fuel out toward the air filter because of the reeds or not?

Heres what mods I have discovered on this machine:
Shear Head Pipe w/FMF Turbine Core 2 silencer
33mm PWK 140 main and a 48 pilot. Needle 3rd clip up from bottom. (Jetting it came with. Cant say its right)
Clamp on carb K&N
No Porting
Shaved spiral head
Maybe a shaved deck due to the 1mm spacer found at the base gasket MacDizzy Theory Possibly...
68mm Wiseco piston

Is the jets in the carb sound anywhere near close? If not Im going to need to buy some jets. What number range should I be looking for.

 

[c_dub1984]

with those mods I'd say the Carb is probally to big for any decent bottom end power I'd look for a smaller Carb 28-30mm. But if u were to continue using that Carb Id say clean the snot out of it and buy some smaller mains starting from your 140 and get down to 125. on pilots I'd

 

[Larry's Shee]

Jetting might be close. Have you cleaned carb? Look closely at float needle valve seat. Set float level. Seems I've read on here that a clamp on filter needs/benifits from a tube to "straighten" the air out before it reaches the carb. How are the reeds? Fresh fuel, plug? Good blue spark?
I've never actually checked a reed valve motor but a piston port 2 stroke will have a "fog" of fuel/air at the carb opening.

 

[c_dub1984]

get down to 35 and try working down and see if it runs any better. Dont forget to plug chop.

 

[c_dub1984]

my last post got split into two parts. Sorry for any confusion.

 

[wwholden]

Ive cleaned the carb with brake clean twice now. Took out the main and pilot jet and cleaned them. Incepted the needle and seat. They looked fine. I havent checked float level. Its got a pair of dual stage reeds in it. Plug looks to have a strong spark. I just thought that if there was fuel coming out toward the filter then its evidently getting more fuel than it needs.

 

[Larry's Shee]

My Blasturd is broke right now so I can't do it, but take the filter boot off your other one and start it and see if you have a simular "fog" at carb opening. I have no knowedge for a pwk so I can't help with float level. Maybe try search on here.

 

[wwholden]

I can't check the other blaster. Lil3mill is PCing the frame and all. I'm sure I can figure out the float level but I'm sure that's not the problem. Ill definatly check it to eliminate that from the list tho.

 

[Larry's Shee]

Well, you could try the reeds from other engine to eliminate that from the mix. I know you just had this engine apart, did you do a leakdown test on it? Heat cycles? Even tho it's not a fresh engine still have to do heat cycles then re-torque.

 

[Larry's Shee]

Just read other thread. I would suggest a comp and squish test on it.

 

[wwholden]

I did a compression test with the 1mm spacer in it and I got 90psi. Without the spacer I get 105-110psi. Yeah its not the best but I know thats not whats causing it to run the way it is. I did do a few heat cycles and then checked torque on the head nuts. Also it has a head stud thats been stripped out at the jug. Any ideas on how to fix this? My main concern for this thread though is the jetting. Does the 140 main and a 48 pilot seem right for this set up. Im thinking the pilot is too big.