KCvale
In memory of KCvale 1959 - 2019
After testing it didn't seem to make that much if any difference other than the exhaust was less restricted compared to most other exhaust types..
Lets all review what an expansion chamber actually does...
The way 2-cycle motors work is to try and do the exhaust and intake in the same up/down/up cycle of the motor so it can fire on each top visit, and because of that a lot of unburned (green) fuel goes out the tailpipe.
An Expansion Chamber (on the right of that animation), named for its peculiar looking fat section, is tuned to push that un-burned fuel back into the cylinder, thus giving each cycle an extra Boost of fuel.
You tune the pipe by the length of the header pipe.
If that pipe is tuned right you are set.
If you are not sure, get a SickBikeParts X-chamber.
http://sickbikeparts.com/expansion-chamber-black-exhaust-pipe/
It is tuned with the short straight copper tube.
It is already tuned for a 48cc, for a 66cc cut the copper tube in half, in essence just butting the 2 copper angle pieces together.
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