You are saying it pops and bangs when you try to go over half throttle?

And this problem is happening no matter what jetting you had in there?

Did, it run properly before the mods were done or did you get the bike in that condition?

Varsey pretty much summed up most of the problem areas.  It could be electrical, I remember someone buying a used igniter off of me and it seemed to solve a similar problem, but would rule out the carb first.  I had problems with my slide and it created some interesting problems that could easily be confused with plenty of unrelated issues.

Right on, so you really don't know when this bike ran properly and if any of the mods are related.  

FILTER, check.
BENT CHOKE ASSEMBLY??  That could be an issue.
SLIDE looks worn was an issue for me. (I got mine from partzilla.com)
I would hold off on electrical stuff for now.
Aftermarket carb, LANCER on here sells a properly jetted kit.

The used bike that had some carb work done...make sure the air jets on to are the correct size AND I would consider buying a stock needle with the white spacer just in case they put the wrong one in.

You want to rule out the carb, before throwing money at electronics IMO.

Also helps if you tell us the year and mileage of the bike.  

Bent choke stem, it's soft brass ,you don't have to call on superman to bend back straight. nothing to lose it's already bent. The direct fit carb is the one you presently have,  changing to an after market carb opens up a new can of worms. You've added a more open air filter ,an unknowingly tuned your intake by extending the passageway from the filter to the intake valve ( that's not bad, but it acts like turbo charging in some rpm ranges which can produce 4 to 7 % boost in fuel air flow) that and a less restrictive muffler ,increases air flow thru the motor , which requires adding more fuel , the stock jetting will probably be to lean. The jetting you ran after the carb rebuild was probably to rich, Your elevation is 951.65 ft above sea level , I would suggest 52.5/ 150 and 3 # 4 steel machine screw for the spacer mod(and retuning the air mix screw) as a starting point . Ohiomoto would probably not but his bike is stock. If you suspect the coil  I would try electrical tape on the coil wire to the sparkplug ( there may be cracks) as higher speeds require higher voltages to jump across the plug gap.( you could run the bike in the dark and might be able to see if the spark is jumping to ground on the head .

And spray the black coating on the outside of the slide itself ,don't even leave a fingerprint on it.

stranglefoot wrote on 06/17/19 at 16:51:25:
------------------------------------------




Very good point!  I had to go back and read everything again and the OP never said anything about the petcock nor did we ask????  That's usually the first thing that gets pointed out. Hard to believe we all missed that.

LANCER wrote on 06/18/19 at 07:36:45:


+1 to that one!
It worked for me!