So I'm currently having a problem where I can't get my bike to go faster then 80 mph. It seems like in the higher rpm's that the bike seems to lose power as well. A little background on the bike.... It's a 2002 883 sportster. I ended up having a scuffed piston, so I upgraded the cylinders and pistons to the Hammer performance 1275 kit as well as installing the dynatek 2000i, rejetting the carb to 185/46, getting screaming eagle ignition wires, new spark plugs, and a brand new battery. In addition to this, I previously had a danmoto highwayman 2 to 1 exhaust, as well as the screaming eagle air cleaner. I've had my sportster for about 3 years and have taken in to around 90-100 mph on the freeway multiple times when it was an 883, so i know it should be capable. The problem began occurring after i tore down the motor and installed the 1275 kit, so I'm wondering if anyone can guide me in the right direction to solve this problem. I've had suggestions that it may be a problem with the carb not providing enough fuel? or air cleaner clogged up? The bike starts right up and runs fine cruising around town... it's just sluggish when i full throttle into higher rpm's trying to pass up cars, and when trying to get in the fast lane on the freeway it can't go past 75 or 80....


PS I set dynatek 2000i, timing, and carb jets/adjustment to the hammer performance recommendations.

 

I will guess you are running Fat and blubbery
I would just guess here without ANY exp in EVO Sporters- that 185 Main is large.
Just a guess

 

185 does not seem out of line for a 1275 with exhaust and free air cleaner. If your confident the carb is fine, I would perform a compression test next.

 

 

so you think i should try out a a 180/45? It's my first go around with trying to tune a carb. any idea for how many turns for the adjustment screw? I have it at about 3.

 

any way to check if the carb is fine or not? I will try to borrow the tools and do a compression test as well.

 

take the air cleaner off. with the bike running look in the carb, there is what looks like a piston in there. It should go up as you rev the bike up. If it doesn't then the rubber diaphragm has a hole in it and you need a rebuild kit (it is not expensive and easy to install) I had the exact same problem on my 883,I put the rebuild kit in and now it goes up to 100 like nothing

 

Check with Dynojet for guidance. The emulsion tube is key, AND it's different than the stock tube.

 

Awesome. I'll check it out, and possibly just rebuild the carb regardless if it isn't too expensive. Any company you recommend to get the kit from?

 

"... I upgraded the cylinders and pistons to the Hammer performance 1275 kit ..."

You didn't say anything about cams. Are you still running the original 883 cams?

If you're still running original cams, that is your problem.