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Bike Runs Terribly After Re-Jetting....

2K views 9 replies 5 participants last post by  93VN750 
#1 ·
I pulled motor, did stator, shaved the ears, re-jetted (40/140F, 40/142R), put on MAC aftermarket pipes, synch'd the carbs, and it runs terribly.

Does not want to rev up, load or no load. I struggled to get to 65mph, don't think it would have gone much faster if I tried.

Idles better than ever, starts instantly.

I don't know if it's too lean or too rich now, but it's bad. Should I have gone ever bigger on the jets due to shave and pipes?

Any thoughts?

Jon
 
#3 ·
There is also mention of shimming the carb needles in the Verses. Did ya do that too?

Going by what it says in the Verses, you end up needing to shim them nearly 1/4 inch each (2-.126" shims per side).

Pick had mentioned adding 4 shims to each needle, but didn't say what size he used.
 
#5 ·
Thanks, forgot, put 2 shims under each needle.

Jon
 
#6 ·
The vent hose is tied to a coolant line out of sight.

Jon
 
#7 ·
From what I have read, this thing screams lean. The 40/140F and 40/142R, + 2 shims is for ear shave alone. I think that adding an aftermarket exhaust (removing the goat belly) requires more when coupled with an ear shave.

The question is how much and where, jets, needle shims, both??

Jon
 
#8 ·
Hate to say this, but this is some of the fun of carbs. you have to play with them. without an o2 sensor to put in the exhaust to see where your burn lies in, that adds to it. I would start with what was suggested, and go from there.
 
#10 ·
I have 8 more shims to play with, I'll order some higher size jets, and begin playing!

Thanks all.

Jon
 
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