TeeCat
One-Mik Wonder
Hi, guys...
Some of you may recall that, just before winter, I had my single-carb conversion running extremely well. I had the jetting right, apparently, and was inducting air through a 4" hot rod-type paper element air cleaner mounted in an ABS plastic plenum. It worked beautifully until the ABS cracked due to mass, vibration, and possibly occasionally being bumped by my left leg while bracing to kick.
Thereafter, I went to the velocity stack that you can see in my gallery pics, largely for space considerations. It has a metal screen with a very unsubstantial piece of foam behind it, and I had planned on going to denser foam. However, this evening, I just wanted to get an idea of whether there would be any substantial change in the way the bike runs. There is.
The bike fires after the first hot kick and comes off the choke quickly, but it wanted to idle VERY high - upwards of 2 grand - until I backed off the idle speed screw. It idles choppily anyway, likely because of the unequal manifold plenum lengths, but tonight was really pretty bad... hunting and the like. As I pulled away from the curb to go around the neighborhood, the bike would stumble badly right off idle, and then sort of "catch up" with itself, and pull hard through 3rd (I never took it out on the secondary road). But consistently, right off idle, it would stumble, and then catch up. Also, on decel, it sounded terrible.
The plugs looked black, but I never really got the bike hot or up to sustained speed. All of the other symptoms, to my mind, suggest leanness.
So here's the question:
I only want to work one variable at a time. It seems logical to try to reduce incoming air by going to denser foam first, and then try again, right? Then, I guess the next step (I can only go so thick on the foam without choking the bike, I suppose) would be the air screw, correct? I'm wanting to see if I can get the air flow back to where the bike was happy by varying breathing (at the air source) instead of jumping right to the air screw or to a larger pilot, which I may not need to do, because the bike ran so well before the air intake broke and had to be re-thought.
Am I on the right track?
Thanks.
TC
Some of you may recall that, just before winter, I had my single-carb conversion running extremely well. I had the jetting right, apparently, and was inducting air through a 4" hot rod-type paper element air cleaner mounted in an ABS plastic plenum. It worked beautifully until the ABS cracked due to mass, vibration, and possibly occasionally being bumped by my left leg while bracing to kick.
Thereafter, I went to the velocity stack that you can see in my gallery pics, largely for space considerations. It has a metal screen with a very unsubstantial piece of foam behind it, and I had planned on going to denser foam. However, this evening, I just wanted to get an idea of whether there would be any substantial change in the way the bike runs. There is.
The bike fires after the first hot kick and comes off the choke quickly, but it wanted to idle VERY high - upwards of 2 grand - until I backed off the idle speed screw. It idles choppily anyway, likely because of the unequal manifold plenum lengths, but tonight was really pretty bad... hunting and the like. As I pulled away from the curb to go around the neighborhood, the bike would stumble badly right off idle, and then sort of "catch up" with itself, and pull hard through 3rd (I never took it out on the secondary road). But consistently, right off idle, it would stumble, and then catch up. Also, on decel, it sounded terrible.
The plugs looked black, but I never really got the bike hot or up to sustained speed. All of the other symptoms, to my mind, suggest leanness.
So here's the question:
I only want to work one variable at a time. It seems logical to try to reduce incoming air by going to denser foam first, and then try again, right? Then, I guess the next step (I can only go so thick on the foam without choking the bike, I suppose) would be the air screw, correct? I'm wanting to see if I can get the air flow back to where the bike was happy by varying breathing (at the air source) instead of jumping right to the air screw or to a larger pilot, which I may not need to do, because the bike ran so well before the air intake broke and had to be re-thought.
Am I on the right track?
Thanks.
TC
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