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Jetting Help Keihin 28mm Pwk’s


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   Good day everyone. I’m working on my freshly built Driveline 421 engine. I just purchased a brand new set of Keihin 28 mm pwk’s and throttle cable. No, I didn’t buy them from eBay. Can’t trust the carbs being sold on there because there’s to much knock off china junk on there. I’ve been working on dialing the carbs in the last few days and I think I’m really close according to the plug chop. Right now I have carbs set at the following 50 pilots ,150 mains, air screw 1.5 turns out and JJH needle set with the  clip in the middle groove. The carbs came with a jet kit ( 6 mains 3 up & 3 Down, 3 pilots 1 up & 1 down ) I’m also having a issue with more than usual exhaust smoke (BLM gave me a warning about it).  For break in I did a pre-mix @ 32:1 with Klotz R50 and VP C12. I’ll be taking the pre-mix down to 40:1 once the tank of 32:1 is empty. 
 

Here’s some information.

    The outside temps here are running somewhere between 70* and 100*+ and it’s roughly around 10ft below sea level here. 
 
Below is my list of mods. 
 

Driveline LP 4mil 421 w/ Aggressive Dune  Porting.
Driveline 4mil  58mm stroke 115 mm rods crankshaft w/ inner and outer koyo 8 ball bearings. 
Chariot Performance head w/ 18cc domes. 
Chariot Performance Intakes w/ V-Force 4 Reeds. 
Chariot Performance HD Clutch basket w/ Driveline HD Clutch kit.                                
Chariot Performance Pan Cake Bearing.    
Chariot Performance Ultra Impeller Kit. 
Pro Design Adjustable Timing Plate. 
Stock Airbox w/ lid removed & Pro Design Pro Flow K&N Filter and outerwear.                
Keihin 28 mm pwk’s.                                           
SLP pipes and silencers.                                    
Pingle Petcock. 

Any advice would be greatly appreciated. 

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