SuzukiSavage.com - exhaust wrap questions

Bobbert Serious Thumper Offline CHOP IT Posts: 836 Los Angeles, CA Gender:	exhaust wrap questions 04/03/08 at 17:39:16 I found that with exhaust wrap on, the bike is lean again. Is this explained by the wrap? Also, I noticed it getting pretty hot down there. Normal?
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thumperclone Serious Thumper Alliance Member Offline PGR rider riding with respect Posts: 6059 Grand Junction Colorado Gender:	Re: exhaust wrap questions Reply #1 - 04/04/08 at 07:13:29 if i understand the theory the wrap keeps the heat in the pipe to help expell the gasses at a higher velocity..could cause too lean??
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vroom1776 Serious Thumper Offline Posts: 2110 Gender:	Re: exhaust wrap questions Reply #2 - 04/04/08 at 07:17:37 .
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verslagen1 YaBB Moderator ModSquad Offline Where there's a will, I want to be in it. Posts: 28884 L.A. California Gender:	Re: exhaust wrap questions Reply #3 - 04/04/08 at 08:10:39 thumperclone wrote on 04/04/08 at 07:13:29: if i understand the theory the wrap keeps the heat in the pipe to help expell the gasses at a higher velocity..could cause too lean?? The gas is hotter to the exit, it doesn't condense as much. I would think that this would cause more backpressure.
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Savage_Rob Serious Thumper Alliance Member Offline Mechanically Inclined Amateur Posts: 6972 Texas (Dallas area) Gender:	Re: exhaust wrap questions Reply #4 - 04/04/08 at 09:33:31 My bet is that, in the process of wrapping the exhaust, something got loosened up and you have a leak. You'll get some good shotgun blasts and popping from an exhaust leak.
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Reelthing

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Re: exhaust wrap questions
Reply #5 - 04/04/08 at 10:25:07

verslagen1 wrote on 04/04/08 at 08:10:39:

thumperclone wrote on 04/04/08 at 07:13:29:

if i understand the theory the wrap keeps the heat in the pipe to help expell the gasses at a higher velocity..could cause too lean??

The gas is hotter to the exit, it doesn't condense as much. I would think that this would cause more backpressure.

spose to reduce the back pressure - keep the exit gas hotter so it is less dense for the gas further up the pipe to have to push against - in actually use on underhood header pipes it does help but for the most part by lower the underhood temp a great deal - on our engines sure seems it would only be a very minor difference - double wall pipe and all

I'd bet on a leak also - the crush seal at the head/headpipe doesn't hold up too well to several R/Rs

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LANCER Serious Thumper Alliance Member Offline Savage Beast Performance Parts Posts: 10661 Oklahoma Gender:	Re: exhaust wrap questions Reply #6 - 04/04/08 at 19:57:40 The most common listed benefit of the wrap is that the hotter exhaust gas (more heat held inside pipe) will exit at a higher velocity, enabling more fuel/air mix to enter the cylinder more quickly, and thereby producing more power in a given amount of time. That is the claim made by the makers of the wrap.
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thumperclone

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Re: exhaust wrap questions
Reply #7 - 04/04/08 at 20:29:09

LANCER wrote on 04/04/08 at 19:57:40:

The most common listed benefit of the wrap is that the hotter exhaust gas (more heat held inside pipe) will exit at a higher velocity, enabling more fuel/air mix to enter the cylinder more quickly, and thereby producing more power in a given amount of time.
That is the claim made by the makers of the wrap.

thats what i ment TY lancer!!! Wink

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joebothehobo

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Re: exhaust wrap questions
Reply #8 - 04/05/08 at 01:43:59

With the wrap on, the exhaust backfires MORE on decell and LESS on shutdown. I would assume that the fact that the wrap making you run leaner by being a more free-flowing exhaust explains the first part. The second part would probably be explained by the fact that the wrap is physically covering the header-exhaust joint, which was never properly secured and surely leaky, reducing back pressure at shutdown.

So, to totally eliminate the shutdown backfire, which is significantly improved, I'd say fix the exhaust-header joint (though the little woof it makes now is certainly livable). To fix the backfire while riding, move up a jet.

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jk Ex Member	Re: exhaust wrap questions Reply #9 - 04/05/08 at 02:04:35 I just think it looks cool. And we all know 'cool' outweighs any pro or con.
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rigidchop Serious Thumper Offline don't feed the drama llama Posts: 1105 ravenswood wv Gender:	Re: exhaust wrap questions Reply #10 - 04/05/08 at 05:10:08 i had it on my chopper and it did look cool for awhile, but its been over done to death. kinda like flat black paint.
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Savage_Rob Serious Thumper Alliance Member Offline Mechanically Inclined Amateur Posts: 6972 Texas (Dallas area) Gender:	Re: exhaust wrap questions Reply #11 - 04/07/08 at 12:51:39 rigidchop wrote on 04/05/08 at 05:10:08: i had it on my chopper and it did look cool for awhile, but its been over done to death. kinda like flat black paint. I went with black ceramic. The flat black look may be overdone but I like it. The ceramic really cuts down on the radiant heat from the pipe too.
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barry68v10 Serious Thumper Offline Posts: 955 Maryland Gender:	Re: exhaust wrap questions Reply #12 - 04/07/08 at 16:46:50 Yes, hotter exhaust gas flows faster. The faster a gas flows for a given mass, the lower the pressure... Now, how much the wrap increases heat is hard to say, but I noticed the same thing, bike seemed to run more lean when I put exhaust wrap on with no other changes.
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barry68v10 Serious Thumper Offline Posts: 955 Maryland Gender:	Re: exhaust wrap questions Reply #13 - 04/07/08 at 16:47:35 BTW, my pipe started turning blue and gold after I put the exhaust wrap on...
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Bobbert Serious Thumper Offline CHOP IT Posts: 836 Los Angeles, CA Gender:	Re: exhaust wrap questions Reply #14 - 04/07/08 at 18:08:39 I definitely have less "kaboom" when I turn the bike off, so the wrap helps prevent air from being sucked in, but its also leaner. I used to have the idle screw about 2.5 turns out and it was a little rich, now its pushing 3 and popping occasionally on downshift
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