is there any modifications you can do to the sbp expansion chamber? like in the silencer part? i know in the stock muffler you could drill holes or cut the inner pipe? anyone tried things??
spb expansion chamber mods??
- Thread starter jasonpadilla
- Start date
Yeah i was going to make a post about increasing the length of the silencer, but i found this one !
Here is a threat that kinda goes into it but I still had more questions.
http://motorbicycling.com/showthread.php?t=19070
I should just dive in and remove the rivets but , heh little paranoid.
Think i would like to do just what BarelyAWake did and double the length of the glasspack.
Here is a threat that kinda goes into it but I still had more questions.
http://motorbicycling.com/showthread.php?t=19070
I should just dive in and remove the rivets but , heh little paranoid.
Think i would like to do just what BarelyAWake did and double the length of the glasspack.
One of the things I do to the SBP pipes is to 'port match' it to the exaust port of the engine. (better flow) 
The other thing I do is to throw away the rubber sleeves & weld all the parts together for a custom fit; Like this...
The other thing I do is to throw away the rubber sleeves & weld all the parts together for a custom fit; Like this...
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Are you able to get the expansion chamber to pass under the bike like that with the stock parts the send with the kit?
yep weld everything together, pull the fiber glass paking and i replaced it with steel wool(stainless), makes it even quieter than when it has the stock pakaging and added header length to total 14.5"
http://www.youtube.com/watch?v=tR4dqSf16xE
http://www.youtube.com/watch?v=tR4dqSf16xE
Hi Ivan, At about 14.5" i find the power to come on well at around 2/3 or 3/4 throttle all the way through to full throttle, i have reed valves and a dellorto carb on my build but my low-end is very poor, it all is in the mid-high end, if i where to get a new header i would have it on about 18-20" in fact so power comes on nicely at 1/4-3/4 then my jetting takes care of the 4/4 throttle, the reed valves defiantly give as much pulling power as the expansion chamber after 1/4 throttle to 2/3 throttle anything below 1/4 is very dodgy and it struggles to go smooth.
Hi Rocksolidperson, thanks 4 shareing that. I have rocksolid head, mild port massaging (widening/ramping), VM16 mikuni,,,, & with sbp shift kit the power is at the moment too high in the range to really make use of 7th & 8th gear (shimano hyperglide cassette), so I might have a play round with lengthening the header to better suit i'm just about to order a pullstart & coupler from rocksolid,,, I might grab a reed block &' cage in a week or 2. CheersThat is sweet! I wish I wasn't so far away from your shop!One of the things I do to the SBP pipes is to 'port match' it to the exaust port of the engine. (better flow)
The other thing I do is to throw away the rubber sleeves & weld all the parts together for a custom fit; Like this...
I may have to have a buddy twist me up something like that.
G'day Rocksolidperson, how ya goin mate. Well its raining again here (sunshine coast) but I just got 1/2 hour blast in. I've got a few different lengths I've been experimenting with & with 2 & 5/16" length plus 45 degree bend & stock pipe & chamber I just got it up to 67 kph, or 41.5 mph in 6th of 8 gears. Its just starting to run out of pipe on wind out so I might knock 1/16" off & see how it goes.i'll check the plug again when cold,,, I think its still a shade richer than optimum, but no 4 stroking. Cheers
Yea you want a light tan colour for your plug, im on holidays right now in surface paradise away from the sand pit (Perth)
Yes, & thats what I've got now that I added a little length to the header. It had been a darker tan than I like but now its probably a touch light. I'll file a tiny bit off the header til it stays on the power a little up top & check it again,,, maybe drop the c clip on the needle a notch if it needs but hopefully it wont. Perth,,, I've heard good things about the west coast, I'll have to get over there one day. Cheers