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Old 03-15-2015, 06:28 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?

I've already done all that as well as a quick port cleanup, widened both intake and exhaust ports by 2mm, then I ramped the piston at the exhaust and transfers down 1mm and in 10mm to aim the transfer flow toad the intake side and help prevent short circuiting. This port job is by far not a hot setup for winning races but for typical street use on a 60lb bike and a 275lb rider I wanted to be sure this engine makes really good torque and still has the ability to Rev to around 7500 rim for a top speed over 30 but not past 35 or so... we definitely want more torque for this setup.
For the acorn nuts I kept them but used 2 washers and checked that there was more than enough clearance before torque the head down... I'll most likely put a Fred head and an expansion chamber on this one before he takes his bike back so this engine will be nice once those 2 upgrades are done. I just gotta remember how much this bike and it's rider weigh to keep it from being too sluggish at low speed. The option is also open for a reed valve which would give even more torque and I'll do the piston mods so it don't lose rim if I do reed valve it.
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