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Been reading the last few postings and i saw something about removing the sub chamber?
Excuse my stupidity but what is it? what does it do? and what will i gain if i remove it??I was told by a non TA owner that it would give the bike more "Omph?" But he could not elaborate on that... :?: :evil:
 

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its the chamber between the header pipes and the tail pipe it reduces noise and gives the cylinders back pressure and according to the bloke from staintune if you remove it or alter it you would have noticeable differences ....increased power....increased noise...and decreased fuel economy. I am going to mod mine I dont know how much i will take off until i cut the baby open to see whats inside . I do want some back pressure
 

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whys the rum always gone?
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i did that mod to the exhaust on my last bike a cb1000 big one :D i didnt notice any difference in fuel consumption, but it sounded a hundred times better. and power was up slightly in the mid range. go for it :D
 
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Why would Honda engineers put in a (complex, expensive?) collector box without good reason?

Having cut up and discarded the bits of the exhaust system you don't like (presumably after the warranty has run out) do you need a tame MOT testing station to get a pass?

p.s. I love the look of the bike with the Laser exhaust! 12 months till the warranty rune out ....... mmmmmmmmmmm hello bank manager!!

Keith
 

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Just fitted a lazer pro duo to the old alp looks the muts nuts, sounds cool, best of all the flat spot I had has gone.. and the bike appears to pull more smoothly 1994 Transalp XVR so no subchamber 50cc less but at least it can breathe :p
 

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Huh?
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Bretton_Kid said:
Why would Honda engineers put in a (complex, expensive?) collector box without good reason?

Having cut up and discarded the bits of the exhaust system you don't like (presumably after the warranty has run out) do you need a tame MOT testing station to get a pass?

p.s. I love the look of the bike with the Laser exhaust! 12 months till the warranty rune out ....... mmmmmmmmmmm hello bank manager!!

Keith
Probably to pass noise and/or emmissions regs.

The MoT noise test is "at the tester's discretion" so smile and show a bit of ankle and you'll be fine!!

-Simon
 

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Slimie said:
Bretton_Kid said:
Why would Honda engineers put in a (complex, expensive?) collector box without good reason?

Having cut up and discarded the bits of the exhaust system you don't like (presumably after the warranty has run out) do you need a tame MOT testing station to get a pass?

p.s. I love the look of the bike with the Laser exhaust! 12 months till the warranty rune out ....... mmmmmmmmmmm hello bank manager!!

Keith
Probably to pass noise and/or emmissions regs.

The MoT noise test is "at the tester's discretion" so smile and show a bit of ankle and you'll be fine!!

-Simon
If you do a search this has been covered in detail not too long back. :roll:

The subchamber is a heavy unit and is not a true catylist as such but I believe a heat tube used to burn (superheat?) spent exhaust gasses along with frest air drawn in through the PAIR system (I've a feeling the bikes run a tad rich - maybe to give something to "burn"??)

It's all in the dubious name of "emissions" - but how making an engine LESS efficient can be more beneficial to the environment is beyond me :evil:

Contrary to popular belief there isn't much of a restriction in there - just an open ended baffle tube within another tube.

My tickover increased by 300rpm after the mod.
Up to about 5500rpm throttle response/grunt/exhaust note AND fuel economy is much improved.
Above 6k not much difference.

This mod is well worth doing.

I do have some pics on memory stick if anyone would be good enough to down load them for me :wink:

If you wait a week or two I'll have some dyno graphs (which Wheelibin has offered to post up for me :lol: ) showing;
1, Stock bike
2, Stock minus subchamber
3, Stock minus subchamber with foam air filter

I don't want to go into carb work but I'm after better economy rather than more performance.

Hope this helps
Phil
 

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Golam Rosewater
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kimberley rider said:
its the chamber between the header pipes and the tail pipe it reduces noise and gives the cylinders back pressure and according to the bloke from staintune............
Isn't that two strokes that depend on back pressure ?

Anyway, mine has a set of custom larger bore downpipes and a Lazer race can, so not much back pressure there. Still does 115mph though.
 

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wheeliebin said:
kimberley rider said:
its the chamber between the header pipes and the tail pipe it reduces noise and gives the cylinders back pressure and according to the bloke from staintune............
Isn't that two strokes that depend on back pressure ?

Anyway, mine has a set of custom larger bore downpipes and a Lazer race can, so not much back pressure there. Still does 115mph though.
Yep - 4 strokes don't need backpressure in the same way 2 strokes do. In fact, to get the best performance from a 4 banger, you generally want the least back pressure possible.

However, if the pipe diameter is made too large in an effort to further reduce back pressure, you can cause more harm than good, particularly to low speed torque, as the exhaust gas velocity will drop too much and you'll end up with less scavenge effect in the headers.

Just been reading this, which has got loads more info on all that kind of stuff. :)
 
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