True duals, are there any gains in performance or economy?

[engprosinc]

I have an 05 Ultra Lehman trike. Is there any advantage to going to true duals vs. the existing stock Harley crossover set up where the rear cylinder dumps into both mufflers? I will have the exhaust off in a few days for some work in the cam chest, so I was considering going to true duals.
What do you say, and why?
Thanks in advance.

 

[John Luciano]

Re: True duals, are there any gains in performance or economy?

Just a guess but having only on Hot pipe per side seems like your one leg would be cooler.

 

[FLTR2008TRIKE]

Re: True duals, are there any gains in performance or economy?

I have an 05 Ultra Lehman trike. Is there any advantage to going to true duals vs. the existing stock Harley crossover set up where the rear cylinder dumps into both mufflers? I will have the exhaust off in a few days for some work in the cam chest, so I was considering going to true duals.
What do you say, and why?
Thanks in advance.

Short answer, no. Unless your going to ride your trike in the upper rpm range. Then it will show a slight gain in HP over the stock pipe. On a basically stock engine with only mild performance work, the true duals will show a slight loss in torque in the lower rpm range. After that with the right tune it all pretty much equals out until the upper rpms.

Any exhaust change will require a re-tune to adjust the ecm settings based on the exhaust change. Most tuners are not a fan of the true dual setups because it takes longer to dial the calibrations in on both cylinders due to having them separate from one another.

If your interested in a different exhaust that has shown good results on a stock or slightly modified engine, the Khrome Werks pipe would be a recommendation I suggest. Its also sold by S&S under their brand name. The front a rear headpipe sections are merged together to give a balanced exhaust flow.

This pipe will work with a 08 and older twin cam touring models >> http://www.khromewerks.com/ look under products and them find the head pipe they offer. You will need the header extentions if you can remove the currents ones you have on your trike.

Keep in mind, when your wanting more power for your trike, you want torque and more torque!! HP is a number very few will ever and I do mean ever see.

 

[SEABILL]

Re: True duals, are there any gains in performance or economy?

I gather that you are looking at putting on a set of headers with pungs for O2 sensors so you can add an auto tuner.

After my '06 Ultra was upgraded with the 95" Big Bore kit, I wasn't happy with the map that the dealer installed on the ECU. The closest shop with a Dyno is in Seattle, WA and just shipping would have been $1400. I chose to buy a tuner with the auto-tune option.

After much research, I chose to go with the stock Harley headers. I found a set of take-offs from an '07 Ultra that already had the pungs on EBay for very little money (don't remember exact price).

 

[msocko3]

Re: True duals, are there any gains in performance or economy?

Short answer, no. Unless your going to ride your trike in the upper rpm range. Then it will show a slight gain in HP over the stock pipe. On a basically stock engine with only mild performance work, the true duals will show a slight loss in torque in the lower rpm range. After that with the right tune it all pretty much equals out until the upper rpms.

Any exhaust change will require a re-tune to adjust the ecm settings based on the exhaust change. Most tuners are not a fan of the true dual setups because it takes longer to dial the calibrations in on both cylinders due to having them separate from one another.

If your interested in a different exhaust that has shown good results on a stock or slightly modified engine, the Khrome Werks pipe would be a recommendation I suggest. Its also sold by S&S under their brand name. The front a rear headpipe sections are merged together to give a balanced exhaust flow.

This pipe will work with a 08 and older twin cam touring models >> http://www.khromewerks.com/ look under products and them find the head pipe they offer. You will need the header extentions if you can remove the currents ones you have on your trike.

Keep in mind, when your wanting more power for your trike, you want torque and more torque!! HP is a number very few will ever and I do mean ever see.

:Agree: I tried a set of V&H dresser duals on my 05 Electraglide Classic, I wasn't impressed. I actually lost some bottom end torque, plus the racket from the louder exhaust was pissing off some of the neighbors.

 

[engprosinc]

Re: True duals, are there any gains in performance or economy?

Short answer, no. Unless your going to ride your trike in the upper rpm range. Then it will show a slight gain in HP over the stock pipe. On a basically stock engine with only mild performance work, the true duals will show a slight loss in torque in the lower rpm range. After that with the right tune it all pretty much equals out until the upper rpms.

Any exhaust change will require a re-tune to adjust the ecm settings based on the exhaust change. Most tuners are not a fan of the true dual setups because it takes longer to dial the calibrations in on both cylinders due to having them separate from one another.

If your interested in a different exhaust that has shown good results on a stock or slightly modified engine, the Khrome Werks pipe would be a recommendation I suggest. Its also sold by S&S under their brand name. The front a rear headpipe sections are merged together to give a balanced exhaust flow.

This pipe will work with a 08 and older twin cam touring models >> http://www.khromewerks.com/ look under products and them find the head pipe they offer. You will need the header extentions if you can remove the currents ones you have on your trike.

Keep in mind, when your wanting more power for your trike, you want torque and more torque!! HP is a number very few will ever and I do mean ever see.

Thanks for the feedback. I think I will leave it alone. I ride one up, and I am definitely not a racer. Probably never went above 2800 RPM since I bought the trike last year. Don't fix what ain't broke.

- - - Updated - - -

:Agree: I tried a set of V&H dresser duals on my 05 Electraglide Classic, I wasn't impressed. I actually lost some bottom end torque, plus the racket from the louder exhaust was pissing off some of the neighbors.

Thanks. I was afraid of that. I will leave alone. If it ain't broken, don't fix it!

- - - Updated - - -

I gather that you are looking at putting on a set of headers with pungs for O2 sensors so you can add an auto tuner.

After my '06 Ultra was upgraded with the 95" Big Bore kit, I wasn't happy with the map that the dealer installed on the ECU. The closest shop with a Dyno is in Seattle, WA and just shipping would have been $1400. I chose to buy a tuner with the auto-tune option.

After much research, I chose to go with the stock Harley headers. I found a set of take-offs from an '07 Ultra that already had the pungs on EBay for very little money (don't remember exact price).

What tuner do you have? I have a Powervision, but no bungs for the sensors.
Did you have someone install the bungs in the headers? How much did they charge?
Thanks.

 

[SEABILL]

Re: True duals, are there any gains in performance or economy?

What tuner do you have? I have a Powervision, but no bungs for the sensors.
Did you have someone install the bungs in the headers? How much did they charge?
Thanks.

I have the Thundermax. The stock headers for the 2007/2008 Ultra already have the bungs in them. It was cheaper to buy a set off of EBay then to have bungs installed.

After doing some research it looked like the only setup that would give me better low end performance was the 2 into 1 headers, and I didn't really want to do that.

 

[FLTR2008TRIKE]

Re: True duals, are there any gains in performance or economy?

Thanks for the feedback. I think I will leave it alone. I ride one up, and I am definitely not a racer. Probably never went above 2800 RPM since I bought the trike last year. Don't fix what ain't broke.

- - - Updated - - -



Thanks. I was afraid of that. I will leave alone. If it ain't broken, don't fix it!

- - - Updated - - -


What tuner do you have? I have a Powervision, but no bungs for the sensors.
Did you have someone install the bungs in the headers? How much did they charge?
Thanks.

You can add 18mm O2 bungs to both front and rear pipes on your current exhaust. The bungs are about $15 each, then you need to have the bung holes drilled into the head pipe and the bungs welded into place on the pipe while its off the trike. Location is key, the O2 bungs have to be located no farther away from the end of the pipe than 6". Closer is better. The 18mm O2s require heat from the exhaust to make them work correctly

The Khrome Werks head pipe I listed a link to has both 18mm & 12mm bung holes. In your case you would use the 18mm un heated O2 sensors that would mount closer to the head. The 12mm are for the newer 2010 & up touring models, they would get plugged.

Once you got the O2 bungs done or purchase the Khrome Werks pipe, than get the Auto Tune kit for the Power Vision you have to use the O2s.