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I have a full race exhaust, all desmogged, open airbox, crankcase breather outside the airbox...I'm running a 68/185 with the dynojet needle at sea level. It runs just fine with no popping, no flat spots, and it rips with 14/48 gearing!

Note that Dynjet jets use different numbers for the sizes than everybody else.

Better to stick with Keihin jets.

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Note that Dynjet jets use different numbers for the sizes than everybody else.

 

I know that, it's a Dynojet 165 which is roughly equal to a Keihin 185.  I even went up to a true 198 and it made no difference up top, so I put the 165 D (185 K) back on.  I'm sticking to Dynojet main jets because I'm using their needle and spring.  I could not tune the stock needle no matter what...something is flawed about its shape and it only works with smaller main jets.  I'm extremely happy with the carb now...I really could not ask for more.  CV carbs are harder to tune but when you get them right they are just as good as a flatside or pumper but with more versatility in terms of altitude and/or ambient pressure/temperature.

 

I'd go down to a 58 main if I were at altitude tho (like 5000' or more).  The 68 with 0 turns out works perfectly.  I had a 58 with 1 turn out and it would still pop under decel and it felt lean down low; with more than 1 turn, it would start to run rough.

 

The 55/155 is really anaemic unless you have a stock intake and exhaust, a shame to keep it that way!

 

Rich is cool and cool, well it's just kool!

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Rich is throwing raw gas out the pipe and loosing power......

 

If you have a pilot jet in a bike and 0 turns out on the fuel screw you are big time rich..

 

 

 

https://thumpertalk.com/topic/271735-how-to-confirm-your-pilot-circuit-setting/

 

 

 

 

we`ve had wideband oxygen sensors mounted on these bikes,,and richer than 52/155 shows rich,,55/158 is way rich..

 

throwing fuel at the fire to cool ...never agreed with that at the expense of power and fuel mileage,,,an oil cooler or big fin head makes more sense and deals with the issue properly...

 

the richest I`d ever jet the CV carb is 55/158 but expect a black exhaust and lots of carbon..

 

 

B

Edited by brianhare
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brianhare, every set up is different, you are assuming a lot.  I also have a Wiseco piston in it and my bike is far, far away from stock.  The spark plug agrees, I'm running just fine with a nice tan color vs. the pale white near green from before.

 

Honda has designed the CV to have no more than 1 turn out on air fuel mixture.  If you need to turn 2 to 3 turns, then you are better off with a bigger pilot jet.

 

Again with the 58, there was still a lot of popping under deceleration which is the most obvious sign of running a lean pilot.

 

The bike seems to have double the power, fuel mileage did not suffer and the bike runs cooler, starts better, idles better, and there are no flat spots, seriously it feels like a different engine altogether.

 

FYI, I consider 12.5 rich and 13.7 lean; anything over 13.7 I consider dangerously lean and 14.7 just plain suicidal.

 

If I ran airplanes the way most people run their bikes, I would burn more pistons than the KKK burns crosses!

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