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Discussion Starter · #1 ·
Yesterday I took my bike to the dyno after getting a R&B LSR 2-1. Theses pipes replaced a set of Samson street sweeper straight pipes.

Well after a couple of runs, I am very disappointed. I am getting 10-12 less on my max power and torque. I thought and read that a 2-1 should always make more than a 2-2 system especially straight pipes

My numbers with the Samson’s were in the low 90's
With the LSR I'm in the low 80's

I don't think the tuners out here a very good, and I don't know a damn thing.
If anyone could give me some ideas as to what to try I would really appreciate it.
I will post some pics of some sheets from both pipes later.

Build
95ci
10.5 comp
SE heads
SE 257 cams
Rivera Mikuni 42 kit
Pilot 22.5 1 ½ turns
97 needle clip 4
Main 165
 

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You don't mention an ignition module. With the LSR, you really need to have someone that knows how to adjust timing for the increased scavenge rate of a pipe like the LSR. You cannot make a drastic change in a part as important as exhaust and just expect to gain gobs of power without re-tuning. You mentioned a "couple of runs". Can't tune a bike in 2 runs and don't know what your numbers were, but you have the makings of a pretty nice build there, so it's probably in the tuning.......usually is!
 

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needs gas

your build should produce good numbers.
perhaps a fatter jetting set up 185/195 would help
as the two into one pipes tend to need more gas in the mix.
to really perform.


good luck

:cheers:
 

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Discussion Starter · #4 ·
GRock said:
You don't mention an ignition module. With the LSR, you really need to have someone that knows how to adjust timing for the increased scavenge rate of a pipe like the LSR. You cannot make a drastic change in a part as important as exhaust and just expect to gain gobs of power without re-tuning. You mentioned a "couple of runs". Can't tune a bike in 2 runs and don't know what your numbers were, but you have the makings of a pretty nice build there, so it's probably in the tuning.......usually is!

Thanks for the reply. I only took it to the dyno to see were the bike stood at this point.
We did a total of about 8 runs while playing with the carb and what was present.
I was just shocked at how much worse it was compared to the other pipes at this time.

The ignition I have is the SE 6200rpm 10 degree unit. Should I get an adjustable unit?
If so which do you suggest?

Now it’s time for me to try to pick the brains of all of you Guru’s to see what I can do to fine tune her.
Worse case is I’ll have to fly one of you to Hawaii to stay at my house while we use one of these dyno’s and tune my bike.:woohoo:
 

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a-b-a test

I would suggest an A-B-A test Your first of pipes are set A.Second set is B
Put it back the way it was(set A ) and see if it repetes.Was all the testing done on the same dyno?Same time of year ( air temp close to the same)? Barometric pressure can change quite quickly and can have a big effect on dyno readings.Did you have the O2 sinfer in the pipe.Allways take pains to make sure your tests are done under as close to the same condisions as possible.Many shops have climite controled dyno cell's. H.D.'s are extremely senisitve to head temp I use a hand held lazer temp gage to make sure all pulls start with the head temp.A oil temp gage is a must also start all pulls at the same oil temp +- @ 5 degrees
I agree the 2 into 1 should make more power and tq. I would be interesting to see what happens with the straght pipes.That is a lot of power to loose with pipes.I fear you may have another problem.If possible check compression and leak down before heading back to the dyno.If everything is ok and you retest with the straight pipes and the power comes back That will be big!
P.S. how much baffling and packing are in the 2 into 1's VS the straights.
Pull the baffel and see what happens.
Big Al
 

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Flyin Hawaiian,

I, too, had a similiar experience. 2003 Dyna Superglide, 88 ci, Crane HI4TC ignition, S&S .570G cams, heads ported & polished with 1.63/1.90 Black Diamond valves, Mik 42 full kit, S&S adjustable pushrods, stock pistons/compression. Rinehart staggered duals. I changed the exhaust to RB Racing 2-1 LSR and lost 1 hp and .5 tq. Running a 165 jet in the Mik and the A/F ratio was practically dead on. We also did seven runs, adjusting the ignition. Best the dyno tech could get was 84.90 hp and 93.87 tq (SAE). He felt I wasn't producing enough compression to make the pipe work. He stated with porting and polishing I effectively lowered my compression. I'm picking up the Dyna tomorrow after having Wiseco 10.5:1 slugs installed.
It's an 88 as I wanted to see what I could do with it. 95 next year.
 

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Discussion Starter · #7 ·
None of the guru tuners want to come to Hawaii.:hmmm:
Well any other advise to tell the guy's here what to do would be great.

By the way I am very serious about flyin one of you out here.
 

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Discussion Starter · #9 ·
GRock said:
You don't mention an ignition module. With the LSR, you really need to have someone that knows how to adjust timing for the increased scavenge rate of a pipe like the LSR. You cannot make a drastic change in a part as important as exhaust and just expect to gain gobs of power without re-tuning. You mentioned a "couple of runs". Can't tune a bike in 2 runs and don't know what your numbers were, but you have the makings of a pretty nice build there, so it's probably in the tuning.......usually is!
I wanted to get more thoughts on if getting an adjustable ignition would help on the tuning my bike? As of now I have the SE 6200rpm 10 degree retard unit.

Also ant other thought would be greatfull..... Also still looking for one of you guru's to come to Hawaii.

Thanks
 

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Discussion Starter · #11 · (Edited)
HDWRENCH said:
Hey send me a ticket whoops make that two and we will be there to tune not a issue.
Two.........:yikes: Let's see if we can work this out. How's one ticket with accommodations for two.:thumbsup:

I also have to see about getting the dyno for you. What about the ignition situation.
 

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IronButt
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Looks like I will be traveling soon. I have never been there but I will also get to meet Mike H . HMMMM been through NE not much to see, this travling thing might catch on LOL . Good Pheasant hunting though.
 

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Lazy 98
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HDWRENCH said:
Looks like I will be traveling soon. I have never been there but I will also get to meet Mike H . HMMMM been through NE not much to see, this travling thing might catch on LOL . Good Pheasant hunting though.
If its ok with F.H. (I haven't asked) I will split your tickets with him, and my wife and I have lots of extra space for the two of you. We are going to Mex. next week, but will be back in mid May. I have been told a few times that I need professional help!:hystria:
 
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