Im confuzzled. Does the XB9 exhaust have the active exhaust valve as well as the XB12? ive read in a few places that the XB9 doesnt. And what happens if a bike that does have one as standard, uses an exhaust without the valve? do you have to re-map it? is it low end power it loses? I think my bike with a non standard exhaust, struggles a little in the 1k > 2k rev range.

Here:
http://www.motorcyclistonline.com/firstrides/122_0310_2004_buell_xb12r_xb12s/
"but credit for the linear power delivery must also go to Buell's new "Interactive" exhaust valve (exclusive to the XB12s) that toggles between two muffler-flow paths to keep the torque curve steady across the rev range."

and here:
http://steveturnbull.co.uk/buell/thexbp ... rmance.htm
"The Standard Buell silencers differ between the 9 and 12 models, in that the 12 has an exhaust valve controlled by the ECM, whereas the 9 does not."

Other sites say they both have it, but with the XB9 you have to do something extra to get the ECM to ignore the lack of valve, whereas with the XB12 it can just be removed.

Or something. I dunno, i'm not a doctor.

_________________
Please be quiet, you'll wake up the other children here.

Vauxhall Nova
Honda Civic
Nissan Skyline
Vespa 50cc
Every Harley Davidson that you hate.

All Buells will struggle below 2000rpm .............. you are lugging the engine which isn't good for it at all.

_________________
2001 X1 2009 1125CR 2006 Uly X3 2010 Uly a fully Maz'd S1 and a 1991 RS1200 Westwind.

i was under the impression Buells had good low end power!?

_________________
Please be quiet, you'll wake up the other children here.

Vauxhall Nova
Honda Civic
Nissan Skyline
Vespa 50cc
Every Harley Davidson that you hate.

Twins don't like pulling below 2k

But low end power depends on your definition of low end - pulling hard a 3k is a dream for IL4s

Under 2k in high gears you're causing the big ends a lot of grief. Keep it between 2.5k and 5.5k and it won't go wrong Though the wheel bearings might or the oil pump drive gear might or the output shaft bearing might Oh and change oil and filter every 2.5k miles. Re the exhaust most on here go for an albert these days. I've have a stealth can on mine, they're quite well made and it's still clean and shiney 6 years on.Though some on here think it looks like a chav pipe cos of the large bore outlet Be warned though any 'free breathing' can will make it pop and bang on the overrun compared to the standard silencer

i guess my definition of 'low' was different then. The only bike ive ever had that wasn't a v-twin was a VFR400 which had a V4, so also had good low end torque too.

_________________
Please be quiet, you'll wake up the other children here.

Vauxhall Nova
Honda Civic
Nissan Skyline
Vespa 50cc
Every Harley Davidson that you hate.

I think the valve on the 12 was just a refinement to optimise what was a legislation led restrictive exhaust system as fitted at the factory (race pipes tend to be non restrictive, loud, and optimised for revs and horsepower), but some would say the valve is not strictly necessary. The unrestricted aftermarket Stealth on my XB9 had buckets more stomp than the standard muffler (within a certain range), but lots of other undesirable traits!

Big longish stroke twins do have good low end power, but often too much, and as DaveH has observed; destructive amounts for their own big ends if lugged at low revs. They are flexible in within a set rev range........'character'.......but that's why we like them!

If you want smoothness down to walking pace and low stressed big ends change into low gear or buy a four cylinder bike!

nah, i don't mind getting my end away!

_________________
Please be quiet, you'll wake up the other children here.

Vauxhall Nova
Honda Civic
Nissan Skyline
Vespa 50cc
Every Harley Davidson that you hate.

My '08 XB9 lightning had the valve in the exhaust, just no servo to operate it.

I've fixed it open since, taken some of the exhaust internals out, added twin exits, a K&N and fuel commander and it pulls nicely right from low down. It's possible to ride virtually on tickover in top gear but as other posts here have already said, if you then accelerate without changing down again it does chug and put unnecessary load on the engine internals, 2000rpm upwards is a lot smoother.

Yeah, what it will and what you should do........

I find when my 9's motor is good and hot down to all the whirly bits inside so all the tolerances are taken up (after 70+ miles); you can sometimes ride down to about 1600 rpm in top if you are very gentle with the throttle. Not that I make a habit of this!

...........it's your engine!

I much prefer it buzzing, that's why I picked the 9 It was an just interesting to discover that a bucket of torque had been reinstated with the last mods and low revs were possible, I did over 200m that day and the engine was definitely warmed up

You may have answered another question wotsmyname! Did you buy your XB9 new or do you know if the muffler with valve was fitted from new?

Did Buell fit the same unit to later 9s and 12s from 08, just deleting the servo from the 9!?

I bought mine new and it came from the factory with the valve in the silencer but there is no servo to operate it so it runs with the valve shut. I would guess it's a standard unit for the range.

Elsewhere on here you can find drawings of the exhaust internals (which is what I used in modifying mine later) but basically with the valve shut the gases travel 3x the length of the box, with it open it allows a short cut. The ECU decides when the valve opens (on the 12s), I think the idea was to give low end torque and high end HP, but I'm sure some of the regulars here will know more.

My first mod was fixing the valve open, made a bit more noise, revved through a bit quicker but lost some low end torque. Later on I made the box basically straight through but retaining the 3 chambers to keep it from sounding like a metal bucket, then added a K&N and fuel commander. Sounds great, goes really well and the torque has come back

which fuel commander?

_________________
Buell X1
Buell xb12s
Buell 1125r
Ebr 1190rx
Bimota Db7
Norton v4rr??



http://www.aph-performance-engineering.com

It's a Kitech unit, got it last year but not long fitted it so it's on the 'out of the box' map at the moment and maybe running a little rich but certainly much better than before.

And seeing as it's you asking Albert, can you do a pipe in black stainless? Just thinking ahead as the can will rot out eventually (already painted it 3 times)