This Is Engineering??
03-06-2010, 04:53 PM
#1
Destructive Tester
Superstock
Thread Starter
Join Date: Oct 2009
Location: N.E. oHIo
Posts: 263
This Is Engineering??
Years ago, when I was the R&D Mgr. at SuperTrapp/Kerker, I was sometimes amazed at the "quality" of the engineering on some OEM exhausts.
This connection, the "Y" to the mufflers on my CheeperHawk, looking into the right, is the most FUBARed I have ever seen! Someone at Honda should be slapped!!
Rex
This connection, the "Y" to the mufflers on my CheeperHawk, looking into the right, is the most FUBARed I have ever seen! Someone at Honda should be slapped!!
Rex
grind it out when you swap from stockers to slip-ons... and then report on the disparity in strength of exhaust pulses... maybe they weren't such slackers after all...
03-06-2010, 06:00 PM
#3
Senior Member
MotoGP
Join Date: Mar 2007
Location: Phoenix, AZ
Posts: 3,132
03-06-2010, 06:01 PM
#4
Senior Member
MotoGP
Join Date: May 2008
Location: San Clemente, CA
Posts: 3,451
Wow! That's amazing. I have stock cans, but that makes me want to take off the right one to see what it looks like.
I put a SuperTrapp all stainless 4 into 1 on my '86 CB700SC Nighthawk as soon as it was broken in with 600 miles. I loved that I didn't have to rejet, I think I had 6 discs installed. I looked up Supertrapp when I bought my VTR, and was disappointed to find out they are all Harley now.
I put a SuperTrapp all stainless 4 into 1 on my '86 CB700SC Nighthawk as soon as it was broken in with 600 miles. I loved that I didn't have to rejet, I think I had 6 discs installed. I looked up Supertrapp when I bought my VTR, and was disappointed to find out they are all Harley now.
03-06-2010, 06:03 PM
#5
Senior Member
Superstock
Join Date: May 2008
Location: S.Dak USA
Posts: 347
Its my understanding that the restrictors in that part of the stock pipe are necessary to tune the exhaust.I could be wrong but,when I posted a question as to what would happen if I ground them out the majority opinion was DO NOT mess with them.
03-06-2010, 08:10 PM
#6
dave
Squid
Join Date: Aug 2007
Location: sydney australia
Posts: 31
I grinded out the restrictor & found I lost power & that is with after market pipes so for me I would just keep it the way honda made them because it takes time to grind them out & more time to weld it back in
03-06-2010, 08:35 PM
#7
Administrator
MotoGP
Join Date: Apr 2006
Location: Kempner, TX
Posts: 4,402
Years ago, when I was the R&D Mgr. at SuperTrapp/Kerker, I was sometimes amazed at the "quality" of the engineering on some OEM exhausts.
This connection, the "Y" to the mufflers on my CheeperHawk, looking into the right, is the most FUBARed I have ever seen! Someone at Honda should be slapped!!
This connection, the "Y" to the mufflers on my CheeperHawk, looking into the right, is the most FUBARed I have ever seen! Someone at Honda should be slapped!!
Definition of Irony???
Grind it out and have at the dyno, please post the AF tables and jetting corrections you made. Would be an interesting afternoon on the Dyno thats for sure.
03-06-2010, 09:53 PM
#8
Destructive Tester
Superstock
Thread Starter
Join Date: Oct 2009
Location: N.E. oHIo
Posts: 263
Actually, I'm going to cut the "Y" off the end of the collector as a 2 into 1, SuperTrapp megaphone, right side exit is in the plans.
They were slackin'.
Rex
Last edited by bjorn toulouse; 03-06-2010 at 09:56 PM. Reason: speelage
03-06-2010, 10:58 PM
#9
Senior Member
SuperBike
Join Date: Mar 2007
Location: Belgium, WI
Posts: 1,611
You will notice a difference with a 2 into 1, and it may not be the difference that you are looking for. If you used two supertrapp cans with the stock y (cleaned out) you would be able to tune your back pressure and get the results that you are looking for (most likely). I would just be cautious, as more flow doesn't mean more power when it comes to the stock engine and its exhaust.
03-07-2010, 05:32 AM
#10
Senior Member
Back Marker
Join Date: Jun 2009
Location: Sudbury ON
Posts: 155
Bjorn,
I had the exact same thing on my Storm. It took me 10 minutes to grind out the my pipe with a de-burring tool. In my case, the bike idled much better. I'm not sure how it affected the mid and top end. A dyno run would confirm the difference.
I can't see why Honda would design a bike with 2 exhausts and then restrict one side by 2/3. Therefore my vote goes to poor workmanship.
I had the exact same thing on my Storm. It took me 10 minutes to grind out the my pipe with a de-burring tool. In my case, the bike idled much better. I'm not sure how it affected the mid and top end. A dyno run would confirm the difference.
I can't see why Honda would design a bike with 2 exhausts and then restrict one side by 2/3. Therefore my vote goes to poor workmanship.
03-07-2010, 11:34 AM
#11
Senior Member
Superstock
Join Date: Jun 2009
Posts: 263
I don't know more air can be good and bad at the same time. Too much air out mean you loosing compression and not enough air restrict you air flow less power. Funny how things work. Anyone dyno yet? or Feel any different? Faster response?
03-07-2010, 11:44 AM
#13
Banned
MotoGP
Join Date: Aug 2007
Location: Lake View Terrace, CA
Posts: 5,942
Dan Kyle did back to back dyno runs back in '98 and showed that the stock, restricted set up made more power with a stock motor. But like always YMMV.
03-07-2010, 12:00 PM
#14
Senior Member
Superstock
Join Date: Jun 2009
Posts: 263
03-07-2010, 01:33 PM
#15
Senior Member
MotoGP
Join Date: Sep 2006
Location: Austin, Tx
Posts: 4,138
Tuning carbs is child's play when compared to exhaust tuning. When I bought mine in came with a TBR on the bike and a stocker on the side. When is came down to which would be my choice for a full JetHot system I chose the stocker.
The TBR was good construction but it was just tubes. Kinda Harley mentality - "we don't give a **** about performance as long as it's loud."
My determination was in a great part due the the wealth of reading in the knowledge base. The shape of the header, the restriction as it passes over the frame member, the 2 into 1 - all there. Even Hawkrider tried it.
This is a battle that I'm going to let other people play. I simply don't have the money or patience of time for ideas the Japs already figured out.
You know? I have one of those Hondas with sudden acceleration problems.
The TBR was good construction but it was just tubes. Kinda Harley mentality - "we don't give a **** about performance as long as it's loud."
My determination was in a great part due the the wealth of reading in the knowledge base. The shape of the header, the restriction as it passes over the frame member, the 2 into 1 - all there. Even Hawkrider tried it.
This is a battle that I'm going to let other people play. I simply don't have the money or patience of time for ideas the Japs already figured out.
You know? I have one of those Hondas with sudden acceleration problems.
03-07-2010, 01:50 PM
#16
Senior Member
SuperSport
Join Date: Jun 2005
Posts: 524
"You know? I have one of those Hondas with sudden acceleration problems"
aka as the twitch of the wrist ?
Back on subject. I took mine out with a hole saw, took all to two minutes...
Didn't notice any difference at that time but later strapped my bike to a friends dyno and got 104 at the rear wheel with K&N filter, stock mains and pilots but with aftermarket needles and RC51 mufflers.
Kai Ju
aka as the twitch of the wrist ?
Back on subject. I took mine out with a hole saw, took all to two minutes...
Didn't notice any difference at that time but later strapped my bike to a friends dyno and got 104 at the rear wheel with K&N filter, stock mains and pilots but with aftermarket needles and RC51 mufflers.
Kai Ju
03-07-2010, 01:58 PM
#17
Senior Member
Superstock
Join Date: Jun 2009
Posts: 263
"You know? I have one of those Hondas with sudden acceleration problems"
aka as the twitch of the wrist ?
Back on subject. I took mine out with a hole saw, took all to two minutes...
Didn't notice any difference at that time but later strapped my bike to a friends dyno and got 104 at the rear wheel with K&N filter, stock mains and pilots but with aftermarket needles and RC51 mufflers.
Kai Ju
aka as the twitch of the wrist ?
Back on subject. I took mine out with a hole saw, took all to two minutes...
Didn't notice any difference at that time but later strapped my bike to a friends dyno and got 104 at the rear wheel with K&N filter, stock mains and pilots but with aftermarket needles and RC51 mufflers.
Kai Ju
sorry to be a noob but its that good or bad? sorry i never dyno my bike
03-07-2010, 02:18 PM
#18
Senior Member
MotoGP
Join Date: May 2008
Location: San Clemente, CA
Posts: 3,451
I agree that it's probably intentional. I just went out and started my '05 with stock cans, and there's an equal amount of pressure coming out of both cans from idle on up. And like stated above, it would be much more of a pain in the *** to reweld those pieces back in there.
I learned about exhaust backpressure back in the mid '60s when I had an exhaust cutout welded on the header pipe in front of the muffler on my '59 Chevy 283 with single exhaust. When I uncorked it completely it lost what felt like 50% of low end power, but it sure was loud. Of course I'm not intending to say that there is any shortage of backpressure in a stock SuperHawk exhaust.
As for sudden acceleration, I've experienced it many times on our 3 Toyota 4x4's. It happens every time I floor it. Well, maybe not so much on my wife's old '86 Extra Cab with the 22RE 4 banger.
I learned about exhaust backpressure back in the mid '60s when I had an exhaust cutout welded on the header pipe in front of the muffler on my '59 Chevy 283 with single exhaust. When I uncorked it completely it lost what felt like 50% of low end power, but it sure was loud. Of course I'm not intending to say that there is any shortage of backpressure in a stock SuperHawk exhaust.
As for sudden acceleration, I've experienced it many times on our 3 Toyota 4x4's. It happens every time I floor it. Well, maybe not so much on my wife's old '86 Extra Cab with the 22RE 4 banger.
Last edited by VTRsurfer; 03-07-2010 at 02:21 PM.
03-07-2010, 02:52 PM
#19
Senior Member
MotoGP
Join Date: Sep 2006
Location: Austin, Tx
Posts: 4,138
[quote=VTRsurfer;256592] It happens every time I floor it. quote]
Yeah, mine does the same thing. It's like the floor has a magnet installed in it. I'll have to take it in one of these days. It's especially embarrassing when the light turns green and the idiot in front of me has the reverse problem.
Yeah, mine does the same thing. It's like the floor has a magnet installed in it. I'll have to take it in one of these days. It's especially embarrassing when the light turns green and the idiot in front of me has the reverse problem.
03-11-2010, 06:24 PM
#20
Senior Member
SuperSport
Join Date: Feb 2010
Location: NY State
Posts: 667
I just did the intersection mod to my pipes this evening - great tip on the hole-saw method - worked perfectly!
Another place to look for improvement is the opening that attaches to the exhaust manifold. There is excess weld bead that can be ground down, it should allow for better exhaust flow.
Before:
After Grind:
Another place to look for improvement is the opening that attaches to the exhaust manifold. There is excess weld bead that can be ground down, it should allow for better exhaust flow.
Before:
After Grind:
Last edited by residentg; 03-12-2010 at 08:52 AM.
03-12-2010, 08:28 AM
#21
Senior Member
SuperSport
Join Date: Jul 2008
Location: Twin Cities
Posts: 505
Has anyone else modified these welds? I currently have my exhaust system disassembled and I did notice these restrictions. I have previously done the grinding at the intersection but now I am tempted to something here as well. Is there a consensus on whether or not there is any benefit?
03-12-2010, 08:45 AM
#22
Senior Member
SuperSport
Join Date: Feb 2010
Location: NY State
Posts: 667
I first learned of this mod from my Honda XR series dirt dikes. Those pipes were half the diameter of the SH pipes. Grinding the bead down on them made a very noticable difference and made them sound nicer, not louder, nicer.
I think that every little bit helps, and this one is free. I used a carbide bit, and then a grind wheel, and then a small wire wheel, on an air die-grinder. I takes a good 30-mins to remove the bead. Still need to do the rear header.
Mobe794 - what did you use to paint your headers and what color did you choose? I was considering doing this myself - any chance of a photo? Engine Ice - I see you are a fellow dirt-biker.
I think that every little bit helps, and this one is free. I used a carbide bit, and then a grind wheel, and then a small wire wheel, on an air die-grinder. I takes a good 30-mins to remove the bead. Still need to do the rear header.
Mobe794 - what did you use to paint your headers and what color did you choose? I was considering doing this myself - any chance of a photo? Engine Ice - I see you are a fellow dirt-biker.
Last edited by residentg; 03-12-2010 at 08:48 AM.
03-12-2010, 12:43 PM
#23
Senior Member
SuperSport
Join Date: Jul 2008
Location: Twin Cities
Posts: 505
The paint I've been using is called VHT ceramic header paint. Flat black. It, and other colors, can be found at most auto parts stores. It won't last forever. About two seasons is max for me, but I do a lot of spirited riding. Sun up till sun down on most Saturdays in the summer. Road debris will slowly sand blast away a few areas. I have found it to be a cheap alternative to Jet-hot.
I used to have it wrapped then painted over (guess I should change my signature). I liked the look of that a lot and it held up surprisingly well. The paint soaked into it and gave it a hard shell. I quit with the wrap after dragging the header a few times at the track. I think I got the dragging situation taken care of now but I just haven't felt like messing with the wrap again.
Sorry, it's a no-go on the pics. My computer took a **** a few months ago. I'm using an old relic I found at my parents house. It's abilities a very limited.
I used to have it wrapped then painted over (guess I should change my signature). I liked the look of that a lot and it held up surprisingly well. The paint soaked into it and gave it a hard shell. I quit with the wrap after dragging the header a few times at the track. I think I got the dragging situation taken care of now but I just haven't felt like messing with the wrap again.
Sorry, it's a no-go on the pics. My computer took a **** a few months ago. I'm using an old relic I found at my parents house. It's abilities a very limited.
03-12-2010, 02:09 PM
#24
I could ride in
SuperBike
Join Date: Sep 2007
Location: Dayton, TN
Posts: 1,729
I ground mine out when I switched to slipons, so its not a clear cut case, but the slip ons were better and the left sure as heck has alot more gas out of it than the right now...
03-13-2010, 07:07 PM
#25
Senior Member
SuperBike
Join Date: Aug 2005
Location: Fort Wayne, IN
Posts: 1,858
Yeah, but rev it up a little and you'll see that the flow evens out quite a bit. I have to believe that under load/rpm/throttle that the flow is pretty close to the same with the stock header. Honda knows what they are doing and this is not coincidence, the design is meant to be that way.
03-13-2010, 08:45 PM
#26
OCMD honorary member
Superstock
Join Date: May 2007
Location: Olympia, WA
Posts: 252
Yeah, but rev it up a little and you'll see that the flow evens out quite a bit. I have to believe that under load/rpm/throttle that the flow is pretty close to the same with the stock header. Honda knows what they are doing and this is not coincidence, the design is meant to be that way.
03-14-2010, 04:11 AM
#27
Senior Member
SuperSport
Join Date: Feb 2010
Location: NY State
Posts: 667
Well, it sure seems strange to me. I think that someone at Honda messed up, and the decision not to address it was based on profits, or maybe it was done to even out left / right exhaust flow so that customers would not complain and cost Honda money to address post production. Having 2 mufflers is cosmetic afterall.
But lets say that it was intentional. It would have been intentional for the stock mufflers, not free flow aftermarket exhausts like many of us have installed. My vote is to remove the blockage at the intersection, and remove the excess weld bead. Besides, I already did both, so I cannot go back
JB
But lets say that it was intentional. It would have been intentional for the stock mufflers, not free flow aftermarket exhausts like many of us have installed. My vote is to remove the blockage at the intersection, and remove the excess weld bead. Besides, I already did both, so I cannot go back
JB
Thread
Thread Starter
Forum
Replies
Last Post
