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20 Posts
Discussion Starter #1
I would like to ask for opinions regarding the following jetting issues. The bike is:
  • 1998 FLHR - 80" Evo
  • S&S Super E carb with K&N air filter
  • SE heads
  • Cometic .030" head gaskets
  • Woods W-6 cam
  • SE Single fire ignition system
  • SE Six-speed transmission
  • SE tappets, blocks, and pushrods
  • Does not seem to be any intake leaks
The motor accelerates hard to about 3,000 rpm in any gear. I don't know what the size of the intermediate jet is, but there is probably too much accelerator pump. When the main jet was a .072, it would creep, very slowly from 3,000 rpm to 4,000 rpm. The bike would not rev more than 4,000 rpm, plenty of throttle left, rotating it does nothing. The plugs looked like the motor was running a bit lean - no blistering, just "white".

I changed the main jet to a .076 and the motor accelerated a bit more quickly from 3,000 to 4,000 rpm and max rpm increased to about 4,300. I have been told that the motor needs a .080 or .082 main jet.

This seems like a big main jet for an 80" evo. Does it sound reasonable that this set-up would require a main jet of over .080? Also, before I tear into the carb, based on the above, what size intermediate jet should I expect to need?

Any thoughts or discussions appreciated.



36 Posts
Sounds like you have some bigger issues here. I have an S&S 88" with a
W6H (590 lift) cam, and super E carb. I'm currently running .72 main jet,
and the elevation here is relatively low. Anything more than say, a .70 main
jet is probably too much for your set up. Either your ignition is the problem
or your carb, not being able to rev past 4 grand is odd, lean or not.
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