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Discussion Starter · #1 ·
My bike is a 2005 FLTRI with the ECM re-flash and the SE Air Filter. I have wanted a True Dual exhaust for my Road Glide for awhile now but hesitated to install one because of the constant feedback I hear about the inevitable loss of low end torque associated with this type of exhaust system.

I finally decided to do it anyway because I wanted to get rid of the heat generated by the cross over pipe. If necessary I was willing to sacrifice a little performance in order to gain a bit of comfort. I had a set of V&H Dresser Duals installed along with a pair of Fullsac Performance re-cored OEM mufflers. The bike ran OK with the ECM Re-Flash but it was very lean so I added a Power Commander and took the bike to a professional tuner. The tuner (Doug at Carl’s Speed Shop in Daytona) ran a separate map for each cylinder sampled at intervals of 250 RPM from idle up to red line. The resulting Dyno chart is attached.

The torque is linear with no apparent loss in the lower range. I no longer need to downshift every time I want to pass. The 17% increase in HP is felt everywhere in the RPM range I use in my daily riding. My mileage on the return trip to Alabama from Daytona averaged 42 MPG. I am very pleased with the end results and I got rid of the oppressive heat generated by that cross over pipe.

I think that my results can be attributed to the talents of the tuner and the good mufflers provided by Fullsac. I think that the tuner extracted exactly what I wanted from my machine after listening to my concerns and inquiring about my expectations, riding style, etc. It is quite possible that the torque loss experience by others is the result of using a “generic” map rather than utilizing a good tuner. Additionally I think that the canned maps revamp the front cylinder mapping only leaving the rear to tag along as best it can. I could be wrong about this but I think that is the case.

An unintended benefit of all of this is the truly great exhaust note provided by the Dresser Duals and the Fullsac mufflers. Deep and mellow exhaust notes coming from each cylinder really sounds great. As a touring rider I was not looking for “noise” and this system works for me. I have to add that although Carl's Speed Shop sells a variety of mufflers the tuner was very impressed with the performance and flow characteristics of the Fullsac's.

I am an touring rider and my needs are different than those of you who chase the performance curve. I value reliability, smooth operation, mileage, etc. What I ended up with meets my needs.

So, for those of you who want a True Dual system but are concerned about the loss of torque I say find a good tuner who can generate a custom map that will meet the needs of both the rider and the bike.
 

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I am sooooo glad to read your post,I have a RKC and put V/H tru duells and just recieved my Fullsac Mufflers the other day,I cant wait to put them on and twist the wick a little,now your post heightens my excitement 10 fold,again thanks for the report
 

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2005 Road King Classic
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Very interesting. I wonder what it would have been with the stock headers and a proper tune?
 

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compareed to other systems?

wkohn said:
Very interesting. I wonder what it would have been with the stock headers and a proper tune?
exactly.

It's not just about a torque dip on your own curve, it's whether your curve could have been higher with a better system. As far as true duals are concerned, that answer is yes.

:wootdnc:
 

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drdevon said:
exactly.

It's not just about a torque dip on your own curve, it's whether your curve could have been higher with a better system. As far as true duals are concerned, that answer is yes.

:wootdnc:
The age old exhaust debate. There is always something better but its comes down to what is better for the person that owns the bike. For me, the stock headers is butt ugly and the heat from the crossover just plain sucks. But that's me. :)
 

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Discussion Starter · #7 ·
drdevon said:
exactly.

It's not just about a torque dip on your own curve, it's whether your curve could have been higher with a better system. As far as true duals are concerned, that answer is yes.

:wootdnc:
Well, if you would have taken the time to read my initial post you wouldl see that for me the elimination of the cross-over was more important than ultimate performance. The bottom line of my post was that you don't necessarily lose performance with the True Duals, not that you would gain performance. If you are chasing the performance curve you probably would opt for a 2:1 collector system anyway.
 

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Those are some good dyno results.

I need to make a trip to Carl's speed shop and get a professional tune.
 

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Discussion Starter · #9 ·
wkohn said:
Very interesting. I wonder what it would have been with the stock headers and a proper tune?
Gee, I don't know. Since I wanted to get rid of the stock headers that question never occurred to me.

For me this was never about gaining power, it was about eliminating the stock exhaust heat, adding a Dual system and not losing any power. The fact that I gained power was an unexpected bonus.

I do know that whatever it would have been with the OEM system would not have been worth enduring the cross-over pipe for another Alabama summer.
 

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jlelliott said:
Gee, I don't know. Since I wanted to get rid of the stock headers that question never occurred to me.

For me this was never about gaining power, it was about eliminating the stock exhaust heat, adding a Dual system and not losing any power. The fact that I gained power was an unexpected bonus.

I do know that whatever it would have been with the OEM system would not have been worth enduring the cross-over pipe for another Alabama summer.
I'm looking at true duals for the same reason as you but I might just take my stock pipes and have them www.jet-hot.com coated. Just to reduce the BQ effect on my legs.
 

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jlelliott said:
Well, if you would have taken the time to read my initial post you wouldl see that for me the elimination of the cross-over was more important than ultimate performance. The bottom line of my post was that you don't necessarily lose performance with the True Duals, not that you would gain performance. If you are chasing the performance curve you probably would opt for a 2:1 collector system anyway.
Nice tone, and good job missing the point. As you will see, I did take the time to read your entire post, and your choice to arrogantly assume otherwise says plenty about yourself.

The feedback you have heard about duals is true. If you had optimized your stock headers with good performance mufflers a good tuner could have done better. Hence, you are giving up torque, because if you had stayed with your stock crossovers and gotten the tuning done on that system that you did with the duals you would havemore torque. You dodge this issue, even in your reply. Wkohn also picked up on it. You lose performance with the duals, you gain it (and more) with a high-quality tune.

You could be more clear if you choose, but would rather come off like someone who invented cold fusion. Your choice.

If you choose to eliminate the crossover (I did) you could also go with better performing headers than duals. Thousands of people have them. I did this and am very happy. i am sure you will be happy with your choice.
 

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Quite true

thatoldbike said:
The age old exhaust debate. There is always something better but its comes down to what is better for the person that owns the bike. For me, the stock headers is butt ugly and the heat from the crossover just plain sucks. But that's me. :)

Sure, get what you like. Did you get rid of your special, EPA-mandated crossover headers? The ones you talked about last time?
 

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Discussion Starter · #13 ·
drdevon said:
Nice tone, and good job missing the point. As you will see, I did take the time to read your entire post, and your choice to arrogantly assume otherwise says plenty about yourself.

The feedback you have heard about duals is true. If you had optimized your stock headers with good performance mufflers a good tuner could have done better. Hence, you are giving up torque, because if you had stayed with your stock crossovers and gotten the tuning done on that system that you did with the duals you would havemore torque. You dodge this issue, even in your reply. Wkohn also picked up on it. You lose performance with the duals, you gain it (and more) with a high-quality tune.

You could be more clear if you choose, but would rather come off like someone who invented cold fusion. Your choice.

If you choose to eliminate the crossover (I did) you could also go with better performing headers than duals. Thousands of people have them. I did this and am very happy. i am sure you will be happy with your choice.
No arrogance intended, and I sure didn't invent cold fusion. Nor was I choosing to be unclear. I do understand and accept that it is possible to get more power with other systems. No argument there. If power was my sole consideration I would have used another type of exhaust system.

There are a lot of folks that want a True Dual system but don't do it because they have been told over and over that they will end up with less power than they now have. I posted my results to illustrate to them that this is not necessarily true if they will seek the services of a professional tuner. That's the point I was attempting, in my inarticulate way, to make. Sorry for the confusion. Have a nice weekend.
 

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Daytona Street Glide

I get excellent performance with true duals. Did not even consider any other system. Just bought what I liked and really liked what I bought. The clean fat look with no clamps at all was an easy choice. Oh yeh, they sound awesome! Come on, how can you beat that?

 

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Discussion Starter · #15 ·
bountyhunter said:
I get excellent performance with true duals. Did not even consider any other system. Just bought what I liked and really liked what I bought. The clean fat look with no clamps at all was an easy choice. Oh yeh, they sound awesome! Come on, how can you beat that?

Beauty is in the eye of the beholder, but in my opinion you have the best looking True Dual system on the market. Hope I get to hear how they sound one of these days. Great graphics too.
 

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drdevon said:
Nice tone, and good job missing the point. As you will see, I did take the time to read your entire post, and your choice to arrogantly assume otherwise says plenty about yourself.

The feedback you have heard about duals is true. If you had optimized your stock headers with good performance mufflers a good tuner could have done better. Hence, you are giving up torque, because if you had stayed with your stock crossovers and gotten the tuning done on that system that you did with the duals you would havemore torque. You dodge this issue, even in your reply. Wkohn also picked up on it. You lose performance with the duals, you gain it (and more) with a high-quality tune.

You could be more clear if you choose, but would rather come off like someone who invented cold fusion. Your choice.

If you choose to eliminate the crossover (I did) you could also go with better performing headers than duals. Thousands of people have them. I did this and am very happy. i am sure you will be happy with your choice.
We have all heard the rumor of bottom end loss. Does anyone have any back to back dyno test to support the myth. I have true duals and don't believe a word of it. I could be wrong and would love for someone to show a dyno test that says I am. Anyone?
RB
 

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Give these a shot

Road Bag said:
We have all heard the rumor of bottom end loss. Does anyone have any back to back dyno test to support the myth. I have true duals and don't believe a word of it. I could be wrong and would love for someone to show a dyno test that says I am. Anyone?
RB
You could chime in here:

http://65.38.172.84/forums/showthread.php?t=72888

You could also ask the tuner at Aces and Eights Harley near Cincinnati - he tunes everything from street bikes to their drag team's bikes.

If you are lucky, you could ask HDMD88, or GRock, if they are around this forum. They will also inform you - maybe you will believe them, maybe not.

However, the Harley crossover does a nice job working with the timing of the engine to scavenge better than a "true dual" system on the smaller engines (95 or 88 inches, for example), and the finer 2:1 systems even moreso - they are exhaustively designed to work with the exhaust pulse waves and the valves in the engine. Really, it's no accident, and no myth.

Hope this helps.
 

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drdevon said:
exactly.

It's not just about a torque dip on your own curve, it's whether your curve could have been higher with a better system. As far as true duals are concerned, that answer is yes.

:wootdnc:
Higher peaks are not always better...I would prefer to give up a few "peak" ponies for a broader curve over a larger rpm range. -2$en#e- Then again, I'm not running a 2-1, so I must be full of $hit:unsure:
 

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Guys,
If you do a little research on GRock's take on true duals, you will find that it's in the tuning. A competent tuner should be able to overcome the torque loss issues (compared with a performance muffler with stock headers) through cylinder-specific tuning. It is my understanding that getting the torque dip ironed out is tedious and time consuming work under certain cam/head/ true dual/ muffler combos.
Grab some beverages and read through his posts, all explained for the one's that care to listen........
 

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I put a set of Rineheart True Duals on my RK and really like the way they look and sound. Don't know how much power I lost, but it runs better than it did stock. If all that mattered was power, I guess I would just go get me a crotch rocket and be done with it.:cheers:
 
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