expansion muffler

aarcher30

New Member
Sep 18, 2014
44
0
0
masontown, pa
Hello everyone, I live in pa and have a 2015 gt80 port matched and with reed valve, speed carb, high compression head, lightning cdi, 41t sprocket, stock muffler with no baffling on a Clair mount schwinn cruiser.

I was wondering what the best expansion pipe would give me my top speed? banana or poo poo? or is there something else?

what's the best carb for this engine, I only have 1/4 throttle
 

mike carter 2

Member
Nov 23, 2011
253
13
18
west virgina
i also have a gt 80 on my bike .i made a 1979 suziki rm 60 x chamber fit on mine.it made all the differance in thewourld in my bike. it went from about 25 mph to about 40.other than that ,sick bike parts sells a very good pipe.i realy think you should go to the high proformance thread in this fourm and research,and or ask the fine members questions that realy know what they are talking about
 

mike carter 2

Member
Nov 23, 2011
253
13
18
west virgina
HEY AARCHER,you realey just made the rite dishion. you asked the rite question.all the answers are here on this forum.there are people on here with a vast amount of info all for the askimg.ive riddin my bike well over a 1000 miles in just over a year.it gets better every day thanks to what i learn here. i check this site weekly to see what people are talking about.see what mods they do and what works and what doesnt .i realy have read most of the posts on this forum going back years to find out how to make my bike run as well as it does .all the info os here,you just have to find it .
 

sbest

Member
Nov 3, 2015
343
2
18
Nova Scotia
I experimented with the some of the available "Poo-Poo" pipes:




And found they offered little advantage over the stock pipe:


Most of any gain was in low rpm torque, pulling away from a stop or up a steep hill, but at a loss of top speed rpm power.

This bike is capable of over 40mph with the stock pipe (and a modified stock head!) and 44t sprocket.
The head pictured is a billet head that does reduce top speed slightly but improves torque at all speeds.
Front right is the best head I have for top speed:

Stock head is at the back.
 
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