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Help! Evo CV Carb Jet Recommendations?

T-Skully

Member
Can anyone recommend jet sizes (low & high speed) for my stock CV carb. I have ‘96 Road King that has a K&N filter upgrade, Andrews EV27 cam, Vance & Hines slip ons and a SE 8,000 limit ignition module. I’m wanting to upgrade the stock carb but not sure which jet sizes to use.
 
This saying Twin Cam will it apply to my Evo also? Will the 46 be the best choice and should I try the 185 or the stock 190? I should have also mention it appears to have had power tube installed by the previous owner. Does this change the jetting options?
 
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This saying Twin Cam will it apply to my Evo also? Will the 46 be the best choice and should I try the 185 or the stock 190? I should have also mention it appears to have had power tube installed by the previous owner. Does this change the jetting options?

Jetting is a bit trial and error on the CV. I think with your Stage 1 upgrades, you can try the 46 low speed, and the 190 high. You might want to put a couple of washers under the needle. If the power tube you are talking about above is the YOST, that should just help atomize the fuel better. Here's a quick test that will tell you if you have too fat of a jet in the top end....

Run the bike through the gears into third gear and run third up to 60-70 MPH full throttle, then chop the throttle about 1/8 to 1/4 back and see if the bike either surges ahead or stumbles then recovers.

If it surges ahead, your jetting is lean
If it stumbles and recovers , your jetting is rich
If it makes no difference, you're pretty close.

Quick and easy, pretty accurate too.

This is from the first link I sent you. See earlier in that link how to evaluate the low speed jet.

TQ
 
This saying Twin Cam will it apply to my Evo also? Will the 46 be the best choice and should I try the 185 or the stock 190? I should have also mention it appears to have had power tube installed by the previous owner. Does this change the jetting options?


Pretty much the same when jetting for the TC or evo, maybe just stick to the 45 in the evo being it is a bit smaller. The mixing of parts from kits will sometimes give you some problems too.
 
The 46 may work, but if there is any sneeze at anytime in the lower rpms or when cold, then I would suggest a 48, especially on a engine with stock compression, as the carb signal will not be as strong, as one with enhanced compression.
 
Find a shop in your area with a Dyno. Takes away all the guesswork. Good dyno operator can give you a readout at all RPMs and save you a lot of time experimenting.
 
Most of you time you're on the needle from 1/4- 3/4 throttle. Here's a baseline for you to start with....45 Pilot N65C needle (27094-88) a 180 or 185 main and the mixture screw turned out 2 1/2 turns out from gently seated. get the idle circuit dialed in first then work your way up to the main, you're only fully on the main from 3/4 to WOT.
 
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