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Old 01-21-2015, 06:50 PM
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Davezilla Davezilla is offline
Motorized Bicycle Elite Member
Join Date: Mar 2014
Location: San Antonio Texas
Posts: 2,710
Default Re: what did you do to your motorized bicycle today?

That's the same exact reason I originally tore into my first engine... it had about 1/8" of crank walk and I just happened to notice it one day when I had the mag cover off, the crank moved really freely then felt like it was locked up, then next time I tried to move the crank I noticed it was moving side to side a lot.
I took that one all the way apart to get the crank out and everything looked just fine, the crank was sliding side to side on the bearings, they were ok too, just felt a little rough due to being so cheap. After I trued the crank I put the bottom end back together temporarily to see what things were like and saw where the play was. I was going to make a few washers to keep the crank centered but at the time i had a lot of other stuff going on so I bought a new Dax lower and put my top half onto, bought a new jug but decided the old jug had better looking ports, the new one was one with smaller transfers that were slanted across the top instead of straight, and the old one already had the transfers cleaned as well as everything else opened up really nice so it would take less time to just make the old jug work on the Dax lower, the old jug only had about 30 minutes of run time on it anyway so it was practically new anyway...

What I think was going on with that setup was maybe they were relying on the crank being a tight fit on the bearings to keep it centered or they machined the steps off the crank or it was missing the spacers or washers... or who knows what they were thinking, and I was surprised it ran so well like that...
Hopefully yours is the same way and you find nothing wrong but the crank walk and can make or get some spacers for it, and also, when I temp installed it again with the crank straight and true it slid side to side even more freely...
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