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weird member
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Discussion Starter #1
I think I need a 46 slow jet, but CVP is "out of stock until November" on 46's.

So I hit up J&P and DK and the only brand of slow jets they have are "Biker's Choice" and "Cycle Pro".

Are either of these brands good or should I avoid them and look elsewhere? Also, which of these two brands is the better option?

Side note, the rest of my jetting is DynoJet (stock slide but DJ needle, tube, main).
 

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Try nichecycle.com they will have OEM parts. Great service. I used them a couple of times when overhauling my carb and a carb for TS.
 

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weird member
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Discussion Starter #3
Try nichecycle.com they will have OEM parts. Great service. I used them a couple of times when overhauling my carb and a carb for TS.
Eh, they haven't any for my carb, and even the ones they do don't have a 46.

I just went ahead and ordered the cycle pro (both a 46 and a 48).

Getting this idle tweaked is all that's left on my tuning.
 

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With CV carbs the only pilot jets I've found that'll work are #42 thru #48. I use the size pilot jet that gets a good idle with the slow air screw turned out 1½ - 2 turns. #46 - #48 usually nails it.
If you can't find the jets let me know, I've got a bag of take outs.
 

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As long as the size is correct, and the threads correct, it does not make any difference whose name is on it!
 

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I think the CV jets are all Keihin made just branded different by the aftermarket dealers. I've got them all and the stampings all look the same.
I've also found that some of the S&S carb parts fit the CVs and vice versa !
 

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weird member
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Discussion Starter #7 (Edited)
With CV carbs the only pilot jets I've found that'll work are #42 thru #48. I use the size pilot jet that gets a good idle with the slow air screw turned out 1½ - 2 turns. #46 - #48 usually nails it.
If you can't find the jets let me know, I've got a bag of take outs.
With CV carbs the only pilot jets I've found that'll work are #42 thru #48. I use the size pilot jet that gets a good idle with the slow air screw turned out 1½ - 2 turns. #46 - #48 usually nails it.
If you can't find the jets let me know, I've got a bag of take outs.
When I first finished building the motor, I was running the same jetting as before (stock 42 slow, 180 main). I immediately knew from the first test runs and during break-in that it wasn't enough and was definitely pretty lean. Got a 44 and 45, swapped to the 44 first and put a 190 main. Then, I finally got to have my dyno run.

After first dyno run, the guy suggested putting a 45. I was 3-½ turns out on the 44 and what it had been doing was when it fully warmed up, real hard to avoid spark knock from a stop. And when I came to a stop, the idle would hang around 1250-1400 for 2-3 seconds before dropping to 1,000. (And I had already replaced the intake gaskets and looked for leaks). It also used to get pretty hot fast at idle (like sitting at a stop light). And this is all ambient temps around 60°, so not even hot days.

Dyno guy said I really would need at least a 45, didn't even touch the mixture screw when I put it in, just brought the idle back down to 1,000. Now it is definitely cooler at idle, and the idle only hangs around 1200 for about 0.5-1 seconds before coming down, doesn't do it quite as often, and now it doesn't spark knock taking off from a stop when hot. But it still gets a little hot (not as bad) at idle. And it will start to want to spark knock if I twist the throttle between 1/4 and 1/2 when it's hot if I am say, going 45 mph in 4th gear. Now normally I wouldn't just get on it like that unless I was up to at least 3K rpm but sometimes, emergency situation, you don't have time to gradually come up or to down shift. Side note, dyno guy also said drop the needle 1 notch and put a 195 main in, which I did.

Another side note, I also had tried raising the needle on the 195 with a single shim washer and that didn't help the issue, just made it a little rougher in the top end and was causing it to pull gas from the main jet at idle (I assume, as the idle came up when I did that, and went back down when I took the shim back out).

That's why I was looking for a 46. Last run I did the other day, showed the mid and top end mix as perfect, but the very low mix is still relatively too lean compared to the rest.

I went ahead and ordered both a 46 and a 48. I'm sure either would work, but when I was tuning it before on the 44, it took running the mixture screw out 3-½ turns before it would even react to the mixture screw being adjusted. So I wanted to try a 46 because going from 44 to 45 made such a huge improvement, I didn't know if 48 would be too much. Other improvements going to the 45 from the 44 were that it was a lot smoother as well in general and accelerating. Also it started a lot easier.

So yeah, I am sure I could make the 46 work way out on the mixture screw (3-3.5 turns), or the 48 and I could have the mixture screw in a more ideal range of 1.5-2 turns.
 
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