Expansion Chamber

jak stoll · #91 (**permalink**) 09-10-2008, 05:15 PM

hey norman :-)
I also noticed when I had the cylinder off of mine that the transfer ports were sorta directional & may need to be re port matched if the cylinder was 180d like you did,,,, I just dident know if you looked at that,,,
way cool though I have to say :-)
take care
JAK

Ghost0 · #92 (**permalink**) 09-10-2008, 06:19 PM

To me this is the simplest solution there currently exists on the market. It requires the least amount of modification and works excellent. It is also mounted out of the way of burning anything except rubber.

jak stoll · #93 (**permalink**) 09-11-2008, 04:01 PM

I cant really tell any difference
I think its way too big & poorly executed :-) I was rushing
take care
JAK

jasonh · #94 (**permalink**) 09-11-2008, 04:45 PM

Quote:

Originally Posted by Ghost0

To me this is the simplest solution there currently exists on the market. It requires the least amount of modification and works excellent. It is also mounted out of the way of burning anything except rubber.

So when will it be for sale?

Ghost0 · #95 (**permalink**) 09-11-2008, 05:36 PM

It is in the works but not the first priority for SBP. Until then if you are interested I can point you in the right direction. The installation has been covered elsewhere on this site.

jak stoll · #96 (**permalink**) 09-11-2008, 09:14 PM

I went about 35 miles tonight & either I dident fill the tank enough (unlikekey) or the pipe has my milage way way down (overscavenging) I mean I ran out of gas 1/2 gallon in 35 miles its a wonder it even ran
it seems to run better in the upper mid range but off the line its a complete dog
Im going to make the chamber much smaller tomarrow
take care
JAK

jrbuerger@mac.com · #97 (**permalink**) 09-12-2008, 06:07 PM

Quote:

Originally Posted by Ghost0

The reason it is sputtering is because your pipe has been altered from how it was designed. The distance from the exhaust port to the beginning of the expansion chamber is a very critical dimension. If this distance is changed the pipe will not work properly. I am sure it works better than the stock pipe but unless tuned correctly it will not offer the performance advantage that it should. These engines have a powerband in the 4 to 6 thousand rpm range. To properly tune a scooter/pocket bike pipe for one of these engines, the recommended distance from exhaust port to the start of the expansion chamber is about 12 inches. This can be altered plus or minus an inch or so to correctly tune it to your gearing and riding style. The attached photo illustrates how to measure your header length.

where did u get ur expansion chamber from!? or did you make it?