Carburetor and Fuel System
Title: CV
jet sizes for 84" pan
Post by RussW on Jun 18, 2007, 2:38am
Not Craig, but my 86" uses a 54 pilot, '88 Sportster needle shimmed up about .020, and a 190 main. (Screaming Eagle K&N intake, true dual exhaust with Samson mufflers)
Post by panacea on Jun 19, 2007, 3:54am
Thanks Russ, I went for a ride tonite, she started up real well useing the enrichener, and seemed to run OK, maybe a little flat, but wouldn't re-start hot. I had a 45 pilot, 85 main,Yost tube, idle screw at 2 turns. sounds like I need a bigger pilot jet, I'll pick up an assortment. Mike
Post by RussW on Jun 19, 2007, 4:54am
Mike,definitely start with a 48 pilot, will probably need larger. I found that if you use a small pilot, you can compensate for it by cracking the throttle plate open a little more to keep the bike running. Problem is, you are now idling using the transition ports to the intermediate circuit. This can give you a little stumble at off-idle speeds, as well as make the idle mix adjustment screw less functional.
Also, you have a Yost tube, did you spend the $$ and get the tuners kit with the xtra needles? If not, and you are still using a stock needle designed for an Evo or TC, you will be real happy with that '88 Sportster needle (less than $10 at your local HD dealer). Makes a world of difference at low speed/midrange.
Post by caschnd1 on Jun 19, 2007, 5:02am
Mike,
I don't have hands-on experience jetting a 84" panhead. On my 74" I run a N86E needle, a 50 pilot jet, and a 175 main. You might need to go up just a little on the main jet for the 84", but I'll bet the 50 is fine for the pilot.
-Craig
Post by panacea on Jun 19, 2007, 11:43am
Russ, yeah the tube came with a kit full of main jets and different needles. The red needle is in there now. I got the kit for free from a friend and installed it a few years ago but never used the carb. I do have a 88 Sportster needle also. Craig, I'll try the 50 tonite. Thanks for the help..Mike
Post by RussW on Jun 19, 2007, 1:10pm
Mike, a few years ago I had a lengthy conversation with a fellow at Dakota Kid carbs. Very helpful guy, not trying to sell me on his conversion work at all. He told me that if I wanted to spend the money, the Yost kit blue needle, set on the center notch, would be a good bet for my motor. Since I was too cheap, I took the '88 Sporty needle option!
Post by panacea on Jun 20, 2007, 11:28am
Russ, thanks for the tip, the power is a bit flat,and won't re-start hot. Mike
Post by Kuda on Jun 28, 2007, 1:05pm
Craig wrote:
On my 74 I run a N86E needle, a 50 pilot jet, and a 175 main.
WOW! You guys are running 50's through 54 pilots! I just put 1000 miles on my '49 FL (with 8-1 and FLH cams, but otherwise stock) with a 45 pilot and 185 main. Starts first kick cold or hot, but if I let it sit for more than 10 minutes or less than 30, it's a bear to start. It ran great otherwise, lots of power, only trouble was a slight detonation going on long steep uphills when it was really hot out (93 degrees). Couldn't gear down 'cause I was runnin' 65-70 mph. So you guys think a fatter pilot and main would help? Plugs looked pretty black when I pulled them, but I haven't done a run-n-chop yet...
-Kuda
'49 panchop (which won first place for Big Twin Radical class at the Rendezvous)
Post by 57pan on Jun 28, 2007, 4:49pm
Kuda,
You're running a 45 pilot and your plugs are still black??? That don't seem right.
What kind of mileage are you getting? IIRC, Craig said he once got about 60MPG on a trip he took with his. I realize, of course, that your sprocket ratios can have a big effect on mileage.
Post by Kuda on Jun 28, 2007, 7:07pm
>You're running a 45 pilot and your plugs are still black??? That don't seem right.
Well, like I said, I didn't do a plug chop (ride hard, cut motor, pull over and check the plugs). I just happened to pull the plugs when I was adjusting the lifters up there at the Vous. 1000 miles round trip (one day each way) and the plugs didn't foul or anything, so it might not be so bad...
>What kind of mileage are you getting?
Funny you should say that. I just switched to 3.5 gallon flat sides for this trip, was running 5 gallons. Running easy 65-70 mph, with some city riding in spots, got to 100 miles on the tank and thought I'd be just about hitting reserve. Got to 110, started riding with my hand near the petcock. Then I hit 120, 130, 140, and finally 150. At that point, I pulled over to make sure it really was "ON" and not already on reserve. Nope, it's "ON." Hop back on and keep riding, didn't hit reserve until almost 164 miles. And that's with a cheap repop speedo that reads 4 mph low at 60 mph. When I filled it up, it took 3.3 gallons. I'm no math guy, but that sounds like a *really* high MPG...
-Kuda
Post by panacea on Jun 29, 2007, 4:20am
Kuda, I worked my way up to a 50 pilot because she caughed a bit on the 48 and even more on the 45. Seems to be ok now. I'm still trying not to thrash on it so no main jet tuning yet, but it does seem pretty snappy! The bigest bonus is the easy starting. I'll check the mileage on the next tank...Mike
