Been riding the White Bike this summer with the 127 and my god is it fun on a open road but learned that 140-150 horsepower is a heat creating machine and know how the Twinkie guys feel with new bikes in the EPA meeting range.

Tuned 80-110 horsepower engines with numbers by the book that create a perfect running engine with no hiccups in any areas BUT NO try that with this engine and you have enough heat to cook popcorn and hiccups from hell and just shut off at a stop sign, head scratching attention is needed with this monster.

On a AFR reader normal engines idle and run in the 13.8 range, this engine will just plain shut off at a 1000-1100 rpm idle or spit out carb in a 13.8 range, had to turn the (Ultima/S&S) air mixture screw out into a rich 12.8 range which took care of that problem. Low to mid RPM range is set at 13.6 which runs fine but will build alot of heat running thru towns in with stop lights, I already have the biggest low speed jet with the kit in and currently installing a bigger low speed jet to cool this baby down but kissing fuel mileage good bye that wasn't bad riding normal but will pay the gas to save a engine.

Conclusion is get it close with a AFR reader and then go back to the old school of adjusting by feel that works for the application so never forget the old ways in a modern world, you might need them.

Oh, by the way, did I say how much fun eye watering HP is

 

you know that carb has a mix change jet for the low hi mix and you found out new tech does not work with old school hot rod power

 

Lil tip for the heat.... I bought a Captain Itch crotch cooler for my 121", that flap of leather does wonders for the heat trust me. But Im running mine to the dyno to get it tuned asap as well

 

I would say I feel bad for ya, but I don't.
Sounds like a nice problem to have, and a helluva lot of fun!

 

Bagger I gotta ask.
When you take off from a stop does your front wheel come off the ground or does the whole bike jump into the air and take off?

 

So hard to stay out of the throttle is the problem, can tame the heat but the addiction is winning!

Doesn't really roast my nuts, just the right leg with the 2-1 exhaust. Jumped the low speed jet up and can tell it richened it up, air mixture screw works best at 1 turn out instead of being at 2 turns before. Idle is slightly deeper with reduced heat on a few test runs, going to Tennessee next week so will see real world riding and test it. Oil cooler will be next project but not going to tackle now.

Let me know what AFR numbers the dyno comes up with to see if he can make it live at normal numbers or goes rich for what the engine is asking for.

 

I was having the same problem with it stumbling at around 1200rpm if I went any lower on rpm it would die. I did the same thing as you. my AFR is right at 12 now at idle @ 1000rpm problem went away
as far as the heat I lava wrapped the head pipes now I can wear shorts and not get burned.
im installing a thunderjet tomorrow so ill be on the dyno again yeah.....

 

Will do, seems like ive got it a lttle lean right now or the timing off a bit, doesnt seem to have the oomph it had before i messed with needles but previously it was popping out carb pretty bad.Got it to stop popping out the carb and only a fewl pops on decel now. Dont have a meter, tuning by ear. Running mikuni 48 btw. Anyone around me have a meter Im buying the beers???????

 

Don't know where the red pissed off face came from?

Yea, you can watch a T-jet crossover on the reader if slightly rich when it comes in, cool little set up

The big engine pulls hard at 13.2 on the big jet in giddy up, the T-jet comes in the AFR's start dropping but going to leave it this way as I know it won't lean out. By the book, the T-jet should stay at 13.2 and is a safety net from running out of fuel but gave up on the book and just going to feed the monster, smile and monitor the fuel gauge

The S&S copycat Ultima may have some S&S fans on edge but they took a performance carb and provided plugged holes for a T-jet plus external bleed, no machine work or tapping needed, saved me some coin. Besides the tuner(myself) causing a once in a while off idle pop, the Ultima has been flawless on the road with no hesitaions, responds to fuel changes. Like it or hate it, the carb works

 

this is what my setup is after 12 pulls on the dyno today intermediate jet is .034 main is .072 air bleed is .074 and t-jet is 130 afr at idle 12.5 off idle it leans out to 13.3 and holds until 4500rpm the drops to 12.6 and at 5000rpm leans back out to 13.6 max HP at 5400 113.5 max TQ at 3400 98 this ultima carb is doing a good job of feeding my 80" build