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Discussion Starter · #1 ·
'02 Softail 95" BB, Scottsman heads / SBC 2 into 1 exhaust, 6200 SE module/coil, Andrews 37G's adv. 2 degs.

I asked this question awhile back and the post took a detour and and I never got any specs or suggestions, and I figure I might as well tweak the carb while it's off because I can't do anything else right now.

I have run my blueprinted and flowed 40 mm CV complete with the D-jet kit/Thunderslide, emulsion tube and D-jet needle, (in the #4 position), instead of the #5 position like the directions said, a 48 slow jet, fuel air mix screw out 1 1/2 turns, 200 high speed jet, on the TC 88" motor. Need to know what adjustments I have to make for the new 95" motor..

Other than feelig flat, (momentarily in the mid range transition to the high speed jet), performance has been great! Quick starting, no hiccups or poping back during decel, and instant throttle response and respectable roll on throttle.

Pulled the plugs to do the 95" build and they're buring perfect, pipe is light chocolate brown, no black smoke and the 88" pistons / valves look optimum, (no excess carbon build up indicating a too rich condition). Actually not bad for 9,500 miles at all.

I was running the torque cones in the SE 2 into 1 SE Pro pipe, with no baffle and the Ness Super Sucker style air cleaner. I'll be removing the torque cones before I reinstall the pipe. Ignition is the SE 6200 rpm module.

Cams I'm installing are the 37 G's advanced 2 degrees with a Woods key, light weight Time Saver Crane adjustables.

My question... Given what I've told you, what adjustment(s) should I make to the carb in the way of baseline jetting, needle position, etc????
Need some advice here, as I want to adjust settings for the additional displacement and cams. Head work is by SBC, Scottsman @ 80 cc, so I'm looking at approx. 9.8:1 compression.

The bike has run a best of 118 mph in the 88" configuration that I described, (and gets there quick), and has made great low end torque with the cones.

Really need some help here baselining the carb for the new motor.

Carb thoughts/suggestions appreciated, (particularly from you guys who have already done this).

Thanks for your continued help and tech advice while I build this motor.

Can't thank you enough for the help.

This truly is a great site with lots of knowledgable folks here!

DLR :huh:
 

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DLRVelocity1 said:
'02 Softail 95" BB, Scottsman heads / SBC 2 into 1 exhaust, 6200 SE module/coil, Andrews 37G's adv. 2 degs.

I asked this question awhile back and the post took a detour and and I never got any specs or suggestions, and I figure I might as well tweak the carb while it's off because I can't do anything else right now.

I have run my blueprinted and flowed 40 mm CV complete with the D-jet kit/Thunderslide, emulsion tube and D-jet needle, (in the #4 position), instead of the #5 position like the directions said, a 48 slow jet, fuel air mix screw out 1 1/2 turns, 200 high speed jet, on the TC 88" motor. Need to know what adjustments I have to make for the new 95" motor..

Other than feelig flat, (momentarily in the mid range transition to the high speed jet), performance has been great! Quick starting, no hiccups or poping back during decel, and instant throttle response and respectable roll on throttle.

Pulled the plugs to do the 95" build and they're buring perfect, pipe is light chocolate brown, no black smoke and the 88" pistons / valves look optimum, (no excess carbon build up indicating a too rich condition). Actually not bad for 9,500 miles at all.

I was running the torque cones in the SE 2 into 1 SE Pro pipe, with no baffle and the Ness Super Sucker style air cleaner. I'll be removing the torque cones before I reinstall the pipe. Ignition is the SE 6200 rpm module.

Cams I'm installing are the 37 G's advanced 2 degrees with a Woods key, light weight Time Saver Crane adjustables.

My question... Given what I've told you, what adjustment(s) should I make to the carb in the way of baseline jetting, needle position, etc????
Need some advice here, as I want to adjust settings for the additional displacement and cams. Head work is by SBC, Scottsman @ 80 cc, so I'm looking at approx. 9.8:1 compression.

The bike has run a best of 118 mph in the 88" configuration that I described, (and gets there quick), and has made great low end torque with the cones.

Really need some help here baselining the carb for the new motor.

Carb thoughts/suggestions appreciated, (particularly from you guys who have already done this).

Thanks for your continued help and tech advice while I build this motor.

Can't thank you enough for the help.

This truly is a great site with lots of knowledgable folks here!

DLR :huh:
IMHO you can't be far off with you current setting. You are changing the displacement of the engine but all other components are the same. The flow characteristics of the a/c and the exhaust are the same, only difference is the amount of air pushed through the motor in a given time frame and as long as the carb does not reach its flow limits you should be OK to ride it to the next dyno and have it tuned.

PS If you change your exhaust configuration (cones, baffles etc.) all bets are off

just my $0.02
 

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IronButt
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As we say you are in the ball park. One thing when you get it dyno tune make sure the tech checks slide speed. He needs to make a Fast Acceleration test. If slide speed is off you will need a spring kit. The thunder slide kits work ok but i have many that allow the slide to pop up WAY too fast giving you a overly rich dip. Use of the stock spring most time will cure this. A good tuner will test the pilot jet, slide speed and the main. These are all different types of test. Just tuning for the 4th gear RO is great on paper, you have to cover all 3 sections of the CV.
 

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Discussion Starter · #4 ·
HD,

Thanks for the heads-up. Didn't think about the slide speed. Incidentaly, last three dyno pulls read AFR of 14.8 @ 2200, peaks to 16.0 @ 2500, dives to 12.5 @ 3000, then steadily recovers to roughly 14.5 from 4000 to 5800. You could see the hp/tq flatten out between 2600-3000 when the AFR dropped.

What is the optimum AFR I'm trying to achieve? All 3 pulls were closely the same with only subtle differences in hp/tq numbers from playing with the air mixture screw on the carb..

Thanks.

DLR
 

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Discussion Starter · #5 ·
ViennaHog said:
IMHO you can't be far off with you current setting. You are changing the displacement of the engine but all other components are the same. The flow characteristics of the a/c and the exhaust are the same, only difference is the amount of air pushed through the motor in a given time frame and as long as the carb does not reach its flow limits you should be OK to ride it to the next dyno and have it tuned.

PS If you change your exhaust configuration (cones, baffles etc.) all bets are off

just my $0.02
Vienna, Greetings... I'm going to run the unbaffled SE 2 into 1 without with the torque cones, and am adding the 37G's with Scottsman heads. I have the SE big bore intake manifold I'm also planning on installing to make up for the smaller CV 40 and feel the velocity that the smaller carb and heads will make will be a good compromise for a larger carb, and should welcome the addition of the larger bore intake, (ie more plenum volume). It works on v-8 performance engines I've built. Hoping the physics apply here on the V-twin..

DLR%[email protected]
 

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IronButt
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That could be slide speed but I would want to see a cruise/ and half throttle roll on fist to see what the pilot is doing. If the pilot jet is off then it will alter the entire fueling process, as the pilot adds fuel 100% of the time. If you have a lean "hit" right off the bottom, it could be the pilot is lean , not enough accel pump, could also be lag time on the AFR pump, location of AFR probe. Many things will cause that. I start with pilot circuit first, as that test will show you slide speed as well ( FA) from there I move to needle/ main as the main jet effects the needle portion. . But bottom line is a GOOD tuner will know this and if he does not look else where for a tuner as you are wasting your time with a tuner that only does RO test's. Just because you have a nice afr with a roll on does not mean that the tuning is complete.

Here is where I run afr. I like to see 13.2 range for pilot, as this will help with the lean cough. In the mid range you can bump up to 13.5-8 to get better fuel milage in the cruise range, above 3800 I like to see it come back down to the 12.8 -13.3. Now this will depend on what the set up likes. If you do not need 12.8 and the bike is burbbling in fuel then lean it out. A 13.5 range is a good start for all out tuning you need to try afr ranges. I have seen where the bike was tuned to 13.5 and it ran well we bumpoed the main up aft dropped to 13 flat and the bike loved it giving us several more hp, with no loss of tq. Then it is on to IGN timing,
 

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Discussion Starter · #7 ·
HDWRENCH said:
That could be slide speed but I would want to see a cruise/ and half throttle roll on fist to see what the pilot is doing. If the pilot jet is off then it will alter the entire fueling process, as the pilot adds fuel 100% of the time. If you have a lean "hit" right off the bottom, it could be the pilot is lean , not enough accel pump, could also be lag time on the AFR pump, location of AFR probe. Many things will cause that. I start with pilot circuit first, as that test will show you slide speed as well ( FA) from there I move to needle/ main as the main jet effects the needle portion. . But bottom line is a GOOD tuner will know this and if he does not look else where for a tuner as you are wasting your time with a tuner that only does RO test's. Just because you have a nice afr with a roll on does not mean that the tuning is complete.

Here is where I run afr. I like to see 13.2 range for pilot, as this will help with the lean cough. In the mid range you can bump up to 13.5-8 to get better fuel milage in the cruise range, above 3800 I like to see it come back down to the 12.8 -13.3. Now this will depend on what the set up likes. If you do not need 12.8 and the bike is burbbling in fuel then lean it out. A 13.5 range is a good start for all out tuning you need to try afr ranges. I have seen where the bike was tuned to 13.5 and it ran well we bumpoed the main up aft dropped to 13 flat and the bike loved it giving us several more hp, with no loss of tq. Then it is on to IGN timing,

Wrench, Can't thank you enough! Already copied your post. Will use your advice as a guide. All I have to do now is find a good Dyno tuner here in Northeastern, MD. Anybody from the MD area have any good recommendations??

Out of curosity, who sells individual pilots. I installed the only one that Dynojet provided in my kit for my specific application at the time. If it is of any consequence, when I installed the needle, I put the clip in pos. #4 instead of #5, meaning the needle is leaner than what the directions called for because I installed the 200 main, instead of the 190 they called for, because of the open exhaust and Ness style super sucker intake.

Thanks again Wrench.

DLR
 
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