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Old 02-20-2015, 08:30 AM
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mapbike mapbike is offline
Motorized Bicycle Elite Member
Join Date: Mar 2010
Location: Central Texas
Posts: 5,379
Default Re: what did you do to your motorized bicycle today?

did some changing on the newest green used to be a fixie bike, drive sprocket needed to be flipped over so offset would give more clearance between chain and tire, the 700c fixie frame is narrower than other frames Im accustom to dealing with and chain started making contact with frame now and then when chain was going through it initial stretching stage, that problem is solved now.

while I had rear wheel off, I decided to remove the single speed 24T freewheel because the one I used was one of the "Great Wall" branded ones and after only about 20 miles of use it was show signs of trouble, the Dicta Brand thats made in Taiwan is a good brand but stay away from the china made Great Wall brand, they're junk as I quickly found out, by the way "Sunlite" bicycle parts brand uses the better Dicta freewheel sprockets.

I replaced the single freewheel with a 5 gear multi speed freewheel, the chain aligned perfectly with second to largest sprocket and time it was all buckled up I didn't need to use the pedal side tensioner I had made for it either so that was nice, bothchains tighten equally now with no indler/tensioner on either chain.

I also drilled two 5/16" holes in exhaust end cap to help flow a bit, I took bike out to do a top speed on the flat test run and I guessed just right on what I kinda thought it was doing, that little mildly built GT5 is pushing that bike dead on 40mph with a 41T rear sprocket, NT carb and kit exhaust pipe that's had the flange ID reshaped to limit restriction by matching the port better.

I didn't use one of my better jugs on this engine that has much nicer ports than the one I did use, it has one of the medium sized port jugs with the slanted/cat eye transfers, I did spend some time cleaning the ports up and getting all the castinghumps and bumps out of all the ports, it has a "Fred Piston" in it with shallow ramps at transfers and I shaved the jug deck to give better compression and it has .025" squish clearance with the square Pedal Chopper type head.

This engine doesn't have the grunt power that my GenIV dax engines have, but its every bit as smooth running and considering how its set up, Im really impressed with it, each time I take it out its running a little better, Im not sure what vendor this engine lower originally came from but its a good one, mg coil was stamped 2012 so its not a new model like the ones dax is selling now and I hope those lowers run as smooth as this one does, this GT5 engine is the smoothest running engine Ive had outside of the dax GenIV lowers.

I've decided Im not selling the Green bike at least for!
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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