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Old 10-30-2013, 11:05 PM
CycleTyrant's Avatar
CycleTyrant CycleTyrant is offline
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Join Date: Aug 2013
Location: Tampa, FL
Posts: 27
Default Need help with muffler.

so a couple weeks ago my muffler fell off while i was riding, and i couldn't find it anywhere on my backtrack. the motor wouldnt start without one to i ordered the stock muffler from, i used two screws and washers to screw the muffler into the motor , but the screws come loose after 10 minutes of riding because my pedals hit it while im trying to ride and start up. any ideas? is the stock muffler too big? this didn't happen with the other one.

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Old 10-30-2013, 11:50 PM
Intrepid Wheelwoman's Avatar
Intrepid Wheelwoman Intrepid Wheelwoman is offline
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Join Date: Oct 2011
Location: Hauraki District, New Zealand
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Default Re: Need help with muffler.

Assuming that it is the same size muffler the flange might be welded on a few degrees off which is why you're striking it with your pedals. Is it possible to tuck the muffler in more closely to the frame? If not you might need to get someone who has welding gear to reset the flange angle for you.
To stop the securing screws from coming undone drill the heads through with a 1/16th drill and tie them together with a short length of safety wire.
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Last edited by Intrepid Wheelwoman; 10-30-2013 at 11:51 PM. Reason: spelling
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Old 10-31-2013, 10:54 AM
crassius crassius is offline
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Default Re: Need help with muffler.

get a round file, file the hole on the motor chain side at the top to make it about 1/8 inch higher, file the hole on the pedal chain side to make it about 1/8 inch lower, tuck the muffler closer to the frame, then tighten

make sure you use the hanger that comes with the kit to hold up the weight of the bottom of the muffler
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Old 11-01-2013, 12:36 PM
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mapbike mapbike is offline
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Join Date: Mar 2010
Location: Central Texas
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Default Re: Need help with muffler.

I bend the tubing so the muffler is farther from pedals in the past when I ran a stock muffler, usually only has to be bent a slight amount, very simple and works everytime in my experience.

just chuck the pipe up in a well mounted bench vise and pull until it moves about a 1/4-1/2" in the right direction and you have problem solved.

this sounds very crude and it is but I have also put tubing if fork of tree and pulled on muffler end to slightly bend pipe for clearance.

as for the bolts coming out, use lock washers under them and put a healthy does of Blue loctite or similar thread locker on before screwing them in.

personally I like using studs on the exhaust and then double nutting them with loctite on threads and they never come loose.
I dont always ride WOT, but when I do..I do my best to keep the rubber side down..Ride safely my friends!
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