HarleyTechTalk

Technical Forums => EVO 1340 => Topic started by: Deye76 on January 18, 2020, 08:27:22 AM

Title: Thunder Jet
Post by: Deye76 on January 18, 2020, 08:27:22 AM
I have a 113" Ultima with the R1 carb (G clone). Only time it started and ran good, no decel pop, was rich, AFR 10.5-1. After dyno tuning, with the AFR in a acceptable range, starts hard, lean up top, and decel pop that would please only those who like the sound of popcorn in a microwave. I've been told my some that the R1 is a POS, and I should get a real G. I had a G on a S&S 100" Evo, ran very well,  should I have a Thunder Jet installed on the G? Would a Thunder jet on the R1 help? or waste of time with that carb? TIA.
Edit: No intake or head gasket leaks

P.S. Not going with a Mikuni.
Title: Re: Thunder Jet
Post by: thumper 823 on January 18, 2020, 09:58:59 AM
This is not the dyno  guy's first rodeo  is it?
He should be able to make a real good recommend ..unless he is a cookie-cutter dyno operator.
I know you know messing and guessing with AFR at the top will have a bad ending.
If you are near Scott at Hillside go see him, of not ask him.
Next-tell me more about no head gaskets, "O" ring?, fire ring?
Thanx
Title: Re: Thunder Jet
Post by: JW113 on January 18, 2020, 10:50:59 AM
If it's popping at decel, and hard to start, doesn't that indicate a problem with the low speed circuit when the throttle plate is closed or just slightly open? T-jet only pulls fuel at full throttle in the upper rpms, so not sure how that would help you with this behavior.

-JW
Title: Re: Thunder Jet
Post by: Deye76 on January 18, 2020, 12:44:56 PM
My question on the TJ was for adding another circuit for all around good manners. I'm thinking it's the carb (R1). The tuner spent a lot of time and I'm confident he knows what he's doing. He tuned my injected RK and some friends bikes , all turned out very good.
Title: Re: Thunder Jet
Post by: capn on January 18, 2020, 12:50:44 PM
Once bought a new r2 e clone could not get it to run right.This was a 88 cube shovel.Put an old e on that I had laying around it ran well.
Title: Re: Thunder Jet
Post by: jsachs1 on January 18, 2020, 05:13:11 PM
I've done a couple of the Ultima clones when they first came out. I never received any negative feedback. With the problems I've been hearing about them, I don't think I could recommend them. S&S, E and G, I do a s**t load of, never had an issue or problem. The majority of the ones I do get a T-jet. [attach=0,msg1330706]
John
Title: Re: Thunder Jet
Post by: capn on January 18, 2020, 05:55:04 PM
If you go with G with thunder jet Im sure jsachs would point you to the right set up so you wont need to get it dyno tuned again.
Title: Re: Thunder Jet
Post by: Breeze on January 19, 2020, 03:40:23 AM
Quote from: thumper 823 on January 18, 2020, 09:58:59 AM
Next-tell me more about no head gaskets, "O" ring?, fire ring?
Thanx




OP stated "no intake or head gasket leaks. Not no head gaskets.
Title: Re: Thunder Jet
Post by: Deye76 on January 19, 2020, 09:28:31 AM
Was hoping Mr. Sachs would see this. Not a race bike, would the S&S G be ok as is?
Title: Re: Thunder Jet
Post by: jsachs1 on January 19, 2020, 02:29:08 PM
Quote from: Deye76 on January 19, 2020, 09:28:31 AM
Was hoping Mr. Sachs would see this. Not a race bike, would the S&S G be ok as is?
You know, S&S carbs can be real finicky, and hard to tune perfectly, depending on your exhaust system. They seem to want some order of back pressure.
As far as a T-Jet, it's another circuit, that most times seems to help/balance overall tuning. JMHO.
John
Title: Re: Thunder Jet
Post by: capn on January 19, 2020, 03:30:21 PM
I got a 120 ultima with the same cam and I run a stock G with the same jets Ultima recommends. I admit it does run a little rich.Im using stock headpipe 97 FLHT with recored stock mufflers. Set up for cruisin not racin. 
Title: Re: Thunder Jet
Post by: Hillside Motorcycle on January 20, 2020, 04:09:34 AM
Thunderjets in S&S E, G, and D series carbs are a great upgrade, turning the 2 circuit carb into a 3 circuit unit.
On the dyno, you can see clearly the tailored gains that are easily established.
We have literally, installed well over 250 of these......always a home run.
Title: Re: Thunder Jet
Post by: Deye76 on January 20, 2020, 08:07:22 AM
Anyone know if a S&S G will work with the Ultima air cleaner?
Title: Re: Thunder Jet
Post by: capn on January 20, 2020, 10:19:14 AM
Yes the Ultima air cleaner will work.
Title: Re: Thunder Jet
Post by: turboprop on January 20, 2020, 12:16:49 PM
Quote from: Deye76 on January 18, 2020, 08:27:22 AM
I have a 113" Ultima with the R1 carb (G clone). Only time it started and ran good, no decel pop, was rich, AFR 10.5-1. After dyno tuning, with the AFR in a acceptable range, starts hard, lean up top, and decel pop that would please only those who like the sound of popcorn in a microwave. I've been told my some that the R1 is a POS, and I should get a real G. I had a G on a S&S 100" Evo, ran very well,  should I have a Thunder Jet installed on the G? Would a Thunder jet on the R1 help? or waste of time with that carb? TIA.
Edit: No intake or head gasket leaks

P.S. Not going with a Mikuni.

This jet package is a good starting point if you add the Thunderjet: 036 int., .084 main, 147.5 T-Jet, 190 air bleed.
Title: Re: Thunder Jet
Post by: Deye76 on January 20, 2020, 04:06:22 PM
Quote from: turboprop on January 20, 2020, 12:16:49 PM
Quote from: Deye76 on January 18, 2020, 08:27:22 AM
I have a 113" Ultima with the R1 carb (G clone). Only time it started and ran good, no decel pop, was rich, AFR 10.5-1. After dyno tuning, with the AFR in a acceptable range, starts hard, lean up top, and decel pop that would please only those who like the sound of popcorn in a microwave. I've been told my some that the R1 is a POS, and I should get a real G. I had a G on a S&S 100" Evo, ran very well,  should I have a Thunder Jet installed on the G? Would a Thunder jet on the R1 help? or waste of time with that carb? TIA.
Edit: No intake or head gasket leaks

P.S. Not going with a Mikuni.

This jet package is a good starting point if you add the Thunderjet: 036 int., .084 main, 147.5 T-Jet, 190 air bleed.
Thank You Turboprop.
The R1 came with a 31 intermediate, and a 80 Main, and ran good but was a little rich. So I take it the addition of a TJet allows larger jets on the int. & main. 
Title: Re: Thunder Jet
Post by: turboprop on January 20, 2020, 04:49:11 PM
Quote from: Deye76 on January 20, 2020, 04:06:22 PM
Quote from: turboprop on January 20, 2020, 12:16:49 PM
Quote from: Deye76 on January 18, 2020, 08:27:22 AM
I have a 113" Ultima with the R1 carb (G clone). Only time it started and ran good, no decel pop, was rich, AFR 10.5-1. After dyno tuning, with the AFR in a acceptable range, starts hard, lean up top, and decel pop that would please only those who like the sound of popcorn in a microwave. I've been told my some that the R1 is a POS, and I should get a real G. I had a G on a S&S 100" Evo, ran very well,  should I have a Thunder Jet installed on the G? Would a Thunder jet on the R1 help? or waste of time with that carb? TIA.
Edit: No intake or head gasket leaks

P.S. Not going with a Mikuni.

This jet package is a good starting point if you add the Thunderjet: 036 int., .084 main, 147.5 T-Jet, 190 air bleed.
Thank You Turboprop.
The R1 came with a 31 intermediate, and a 80 Main, and ran good but was a little rich. So I take it the addition of a TJet allows larger jets on the int. & main.

Not really. The combo I gave you is from a tuned 124. Should be a little rich for your 113 but thats a good place to start from. Would rather start rich/safe and slowly lean the various circuits until they are ideal.
Title: Re: Thunder Jet
Post by: Deye76 on January 20, 2020, 05:19:46 PM
 :up: :up:
Title: Re: Thunder Jet
Post by: prodrag1320 on January 21, 2020, 04:29:34 AM
the T jet is a very nice addition for S&S carbs,we have a lot of experience installing & using them (have have up to 3 of them on some of our larger CID pro gas bikes) but what we`ve noticed over the years is most people (racers & street riders) really have no clue how they work,what they are actually for & how to tune them.a t jet is a extra tuning circut so a smaller main jet can be used so the chance of a stumble transitioning from int to main jet can be done,that said with a adjustable air bleed,the transition itself cam be moved to higher (or lower) rpm`s.my suggestion would be to get a real S&S carb,see if that cures the problem before going with a t jet,
Title: Re: Thunder Jet
Post by: Deye76 on January 21, 2020, 06:53:25 AM
"get a real S&S carb,see if that cures the problem before going with a t jet,"

Makes sense, as I have zero experience with a TJ. Appreciated.
Title: Re: Thunder Jet
Post by: Hybredhog on January 21, 2020, 09:42:46 AM
   While we're on the subject, I putting back together a 80" shovel with 9:1 comp.,  a Andrews #1 cam, and for now some 2" drags with baffles. The Carb that this came with is a S&S E with a TJ with a 102 Mikuni jet, .0295int, 72 main, and a 120 Mikuni air bleed. It is kind of over kill for a relatively stock build, was running way rich, and it came out of Iowa . If it didn't have the TJ, I'd start it out with a 28int., and a 64-66 main, as we're at 4K ft. elv.. So what would you TJ experienced guys call in for jetting. I'm not apposed to getting rid of the TJ.
Title: Re: Thunder Jet
Post by: Hillside Motorcycle on January 22, 2020, 04:13:38 AM
Quote from: prodrag1320 on January 21, 2020, 04:29:34 AM
the T jet is a very nice addition for S&S carbs,we have a lot of experience installing & using them (have have up to 3 of them on some of our larger CID pro gas bikes) but what we`ve noticed over the years is most people (racers & street riders) really have no clue how they work,what they are actually for & how to tune them.a t jet is a extra tuning circut so a smaller main jet can be used so the chance of a stumble transitioning from int to main jet can be done,that said with a adjustable air bleed,the transition itself cam be moved to higher (or lower) rpm`s.my suggestion would be to get a real S&S carb,see if that cures the problem before going with a t jet,

^^^^^^^
Yes.
Tuning them is key.
The results clearly speak for themselves.
Title: Re: Thunder Jet
Post by: prodrag1320 on January 22, 2020, 04:51:04 AM
Quote from: jeffscycle on January 21, 2020, 09:42:46 AM
   While we're on the subject, I putting back together a 80" shovel with 9:1 comp.,  a Andrews #1 cam, and for now some 2" drags with baffles. The Carb that this came with is a S&S E with a TJ with a 102 Mikuni jet, .0295int, 72 main, and a 120 Mikuni air bleed. It is kind of over kill for a relatively stock build, was running way rich, and it came out of Iowa . If it didn't have the TJ, I'd start it out with a 28int., and a 64-66 main, as we're at 4K ft. elv.. So what would you TJ experienced guys call in for jetting. I'm not apposed to getting rid of the TJ.


your very close with the jets your thinking about,66 or 68 main jet though.see how it runs,then mess with the t jet
Title: Re: Thunder Jet
Post by: pwmorris on January 23, 2020, 05:12:24 PM
Forget the TJet until you sort out that "carb".

"Lipstick on a pig"

https://en.wikipedia.org/wiki/Lipstick_on_a_pig

Never liked the clones myself, and do a search.....many feel the clones are junk. You decide-
Get a real S&S, and start from there. Start from a potential problem....you get what you get....
No shortcuts.
S&S is King....period.
Title: Re: Thunder Jet
Post by: Racepres on January 24, 2020, 06:26:10 AM
Quote from: pwmorris on January 23, 2020, 05:12:24 PM
Forget the TJet until you sort out that "carb".

"Lipstick on a pig"

https://en.wikipedia.org/wiki/Lipstick_on_a_pig

Never liked the clones myself, and do a search.....many feel the clones are junk. You decide-
Get a real S&S, and start from there. Start from a potential problem....you get what you get....
No shortcuts.
S&S is King....period.
I have Yet to see one in person that is any good at all!!!! Ya get what ya Pay For... or from China???? Maybe Not.
Title: Re: Thunder Jet
Post by: Deye76 on January 26, 2020, 03:57:22 PM
"I have Yet to see one in person that is any good at all"

How many have you actually worked on?