about the expansion chamber

GoldenMotor.com

Elixys

New Member
Sep 14, 2010
127
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Midland, TX
hello from Texas everyone,

I just bought an expansion chamber for my exhaust from gasbike.com and wanted to know if i still need the stock muffler at the end of it or not. i guess what im getting at is this, will the expansion chamber serve as a muffler or will i still need to put the muffler on after the expansion chamber.
 

BarelyAWake

New Member
Jul 21, 2009
7,194
21
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Maine
Assuming ya mean this 'un;



...in which case there's not much of a chance of getting any sort of silencer/muffler on that unless ya wanna fabricate something - so I guess the answer is "no" lol

That one is pretty loud BTW ;)
 

Elixys

New Member
Sep 14, 2010
127
0
0
Midland, TX
also i forgot to mention im having some trouble with oil residue seeping out from around the spark plug area. I know that I am running rich through the carb and I set the needle to the highest notch which seemed to help out quite a bit but I know that its still running rich. Im not sure what to do about it other than I did order one of those CNS carbs and that should be in in a few days along with the expansion chamber, but i could use some help with getting my carb jetted for a leaner mixture. maybe the new carb will have some better results.......any helpful tips? Oh and I tightened the spark plug to the point that I was worried about it.....maybe some teflon tape around the threads?
 

Elixys

New Member
Sep 14, 2010
127
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0
Midland, TX
and i do have access to an arc welder so fabricating something to the end of it isnt out of the question. I just have to be careful not to melt a hole in the damn thing
 

BarelyAWake

New Member
Jul 21, 2009
7,194
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0
Maine
The spark plug should have a crush washer, check to see ifn it's still there... if yer running the kit plug ya might as well try a new NGK B6HS first as it can't hurt to try lol

Thing is the threads in the cylinder head may well be not the best & the china plugs are defo not lol, but I don't think teflon tape will hold up to the heat *shrug* mebbe...

Seepage around the spark plug has nothing to do with it running rich BTW, I'd double check the plug electrode's coloration to make sure it's a nice coffee/tan :)
 

Venice Motor Bikes

Custom Builder / Dealer/Los Angeles
Mar 20, 2008
7,271
1,810
113
Los Angeles, CA.
also i forgot to mention im having some trouble with oil residue seeping out from around the spark plug area. I know that I am running rich through the carb and I set the needle to the highest notch which seemed to help out quite a bit but I know that its still running rich. Im not sure what to do about it other than I did order one of those CNS carbs and that should be in in a few days along with the expansion chamber, but i could use some help with getting my carb jetted for a leaner mixture. maybe the new carb will have some better results.......any helpful tips? Oh and I tightened the spark plug to the point that I was worried about it.....maybe some teflon tape around the threads?
Oil around the spark plug means you either need to tighten the plug, or the plug doesn't have the crush gasket on it.
 

Genisisonyx29

New Member
Jul 8, 2011
207
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0
Merced California
so did you ever get ur x pipe put on? id like to know how it performed. im considering buying one, i like the the one you got has longer pipe so theres room to tune it lol. hows the low end torque with this thing? wheres its powerband at?
 

Genisisonyx29

New Member
Jul 8, 2011
207
0
0
Merced California
thats a cool bike there. u have a nice frame that would look great with tank in it. the bar under the top bar reminds me of a sportsman flyer. i like the sbp x pipe but i want to try and see if make the bananA pipe better by doing some custom stuff.
 

mew905

New Member
Sep 24, 2012
647
9
0
Moose Jaw
Remove the carb. Remove the float bowl. Remove the fuel jet. Be mindful of fuel in the carb. It does not make for a good cologne.
Also, tighten the jet up with a pair of pliers, both the actual jet and the long nozzle it seats into. I thought I could just do it hand tight, and after only a few meters of running the motor, the jet vibrated loose and fell into the float bowl, where going anything more than 1/2 throttle would make it bog down significantly (it almost literally sounds like the motor is running under water)

Header length (the distance between the jug's exhaust port and the actual expanded part of the exhaust pipe) is what sets where the powerband is. Shape and diameter determine how long or potent the boost is. The SBP pipe is fully tunable, allowing you to get either mid, low, OR high end power, but not all 3 (though I dont doubt it would help all around). The banana pipe because it is not adjustable, only allows high end power (to be honest, the 48cc would see the biggest gains I would think, being at top RPM would set the pressure wave right around the middle) unless you add headers or a custom pipe to set the banana pipe further from the port. There are those with much longer expansion chambers (usually custom made or off of dirt bikes) that get far more power all throughout the powerband than any expansion pipe you can buy for these motors. If you want to learn a LOT about these motors, . If you're new, alot wont make sense to you at first, just work little by little. I found myself saying "THAT's what he was talking about!" alot as I worked on the motor, and I progressed, now alot more of the site makes sense to me.
 
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