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05 EFI Roadking with 107 ci that I can't get a good dyno tune (SERT). Options take it out of state (3-4 day round trip, gas, motel, dyno costs etc) or convert it to carb.

Builder can tune it if its carb. For those of you that have made the EFI to carb transistion do you have any regrets. Wondering about the advantages & disadvantages of doing this.
 

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my suggestion? don't do it. fi is much better. i would either go with a closed loop system like t max or twin tec wego. Another suggestion is look at the HQ protuner it will work with sert.. i'm in the same shape I live in ohio too. bob
 

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A good dynotuner could tune any 107 with a SERT. You need to take it to a good Harley indy.
 

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The Anti-RUB
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What do you mean you can't get it tuned right? Most people who say that either took their bike to a crappy tuner, have something wrong inside the motor effecting performance or their expectations of how their motor should run with the components they have installed are unrealistic.

Carb has the same tuning voodoo that EFI does. You gotta have the right size jet, venturi (sp?) etc etc etc, same with EFI just its computerized not mechanical. The concept is the same (controlling the fuel going into the motor). The major benefit, in my opinion, is that EFI will adapt to your riding style as well as road conditions. For example, if you take a ride from sea level into the mountains the EFI system will adapt to the changes in air temp and altitude to keep the bike running properly. I'd like to see a carb do that (without you stopping every couple miles and whipping out some screw drivers to adjust the carb to the current road conditions).
 

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Great tuner !

sawdust236 said:
05 EFI Roadking with 107 ci that I can't get a good dyno tune (SERT). Options take it out of state (3-4 day round trip, gas, motel, dyno costs etc) or convert it to carb.

Builder can tune it if its carb. For those of you that have made the EFI to carb transistion do you have any regrets. Wondering about the advantages & disadvantages of doing this.
I know a good tuner 8 hours from you who will do it reasonably and in one day and likely let you watch if you can refrain from too many interuptions. He will not rest until its right. His 107 Road King did 120 ft.lbs. and runs like a raped ape without drivability issues. Did I mention he was taught by Doc ! See post #149 page 10 in the "top Tuners" thread. If you ride his King, there is no way you will ever want to switch to carb !
 

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Fastest Chkn N the South!
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Why do people think that carbed bikes necessarily have trouble with altitude changes? I've been from sea level to 9000' and back many times on several different carbed bikes and have NEVER had any trouble in doing so. Maybe it's more of a problem on badly tuned (rich) or with non-CV carbs?
 

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I have a CV Carb and was concerned about altitude also but my mechanic who also has a CV Carb assured me that I won't have a problem at all, he has been up in the mountains out west numerous times to over 9000ft and said his bike runs perfectly. I have been to a little over 3000ft and had no prob but I know that isn't really that high.
I do however enjoy reading all the posts about people who have popping on decel....Seems like the norm around here and everywhere else.
Never happens on my Carbed bike
 

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sawdust236 said:
05 EFI Roadking with 107 ci that I can't get a good dyno tune (SERT). Options take it out of state (3-4 day round trip, gas, motel, dyno costs etc) or convert it to carb.

Builder can tune it if its carb. For those of you that have made the EFI to carb transistion do you have any regrets. Wondering about the advantages & disadvantages of doing this.
Hey......I just switched my 2008 Corvette back to a 6 volt electrical system..........WOW.............What a difference................+SMSH+ :wacko: :whistle:
 

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HDSG said:
Hey......I just switched my 2008 Corvette back to a 6 volt electrical system..........WOW.............What a difference................+SMSH+ :wacko: :whistle:




:roflback: :roflback: :roflback:






{salute( :spank: {salute(
 

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Discussion Starter #13
Actually my bike currently runs best at higher elevations and horrorible at sea level. I know its not properly tuned, 4 times to date. Kind of tired of guys that can't dyno right and making the trade-off of going a ways to get it dyno'd (1 last time) or just convert to carb and forget about dyno'ing.
As a side note Zippers recommended against putting a TMAX on because they had no maps that would work with my build.
 

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Red Rider @ 43rd & 7th
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I've seen a lot of post where guys have trouble getting the SERT to tune - and a lot where they swear by them as well. I used a PCIII - there are a thousand maps available on line - you can find one to get you close and do the fine tune yourself. THere are a ton of maps for a PC posted in here also. If you can find someone to tune your SERT saty with it, If not, try a PCIII. But definately stay with EFI.
 

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Iron Butt, SS2000
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It Ain't Rocket Science, is it ZEN/VOODOO ???

I can imagine how frustrated it would be to pay for a tune and get crap but still, all you need is a good tuner. Do your research, don't just go to a guy that another guy said did ok for him. Find someone that several guys have used and liked. NOT guys that bought downloads. Guys that each had unique builds that required a good tuner. Good tuners know rocket science and Zen/Voodoo. That's who you're lookin for. They are around. They don't need to advertise much. You gotta find them.

Your bike, your call maybe you'd be happy with a carb I don't know. I suppose lots of guys like 6 Volt systems.


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The Anti-RUB
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sawdust236 said:
just convert to carb and forget about dyno'ing.
Since when does having a carb remove the need for a dyno? Dyno'ing a carb is just as important as dynoing an EFI...

That said, I have been running the canned map from my SERT for my size motor etc since I bought it and have had no problems. Runs great at sea level (Santa Cruz, CA) all the way up to 6000 feet (Truckee, CA). Made that run with my girlie on the back this past summer. No hickups, misfires or backfires. In other words, there is nothing making you get your bike dyno'd (EFI or carb). The canned maps/jets are pretty good in and of themselves.

If it aint broke, don't fix it.
 

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155" R&R TwinCam
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Some of us learned a long time ago before Dyno's how to tune a motor.As far as I am concerned for those of you not knowing how, a Dyno is a must have.
 

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Iron Butt, SS2000
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Two Identical Builds

Except for one has a carb and the other has EFI.

Both tuned by the best.

Which one has more power across the entire rpm range?

Which one runs smoothest?

What would be the typical "buy in" do do each configutation correctly? (I suppose "correctly" would be a tough one to nail down, think efficient use of $)

What might be the differential $/HP on one vs the other? (eg. this method gives three more top end HP for $250 or even better would be to find out that one way can yield more HP across the board for LESS money) Remember, we have to include all costs, parts labor, tuner.
 

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dog155 said:
Some of us learned a long time ago before Dyno's how to tune a motor.As far as I am concerned for those of you not knowing how, a Dyno is a must have.
I agree. But if you want the most out of it, you need to Dyno it.

I got one of each. I don't see what all the whining is about FI. I am sure it could be tuned to run better, but runs fine. Little stumble on take off.

Be nice to find a map to use, until I get it Dynoed. HINT-HINT
 
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