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Old 12-31-2013, 10:08 AM
rogergendron1's Avatar
rogergendron1 rogergendron1 is offline
Motorized Bicycle Elite Member
Join Date: Sep 2013
Location: woburn ma
Posts: 882
Default Re: what did you do to your motorized bicycle today?

i have pleanty of micro drills .......................... they are in new hampshire 75 miles away at my fathers machine shop though ! i took my vernier caliper and went around the house measuring a bunch of paper clips and saftey pins til i found a pin that was exactly .74mm just about 2 jet sizes larger, right where i wanted it to be, so i reamed it out with that and its around a .72 or .73mm jet now as the pin still fits a little snug so its a lil smaller. if i need more i will go back and ream it out some more with the same pin till it slides through easyer

something to think of if your in a pinch and are running lean and you dont have any micro bits around, just use a small saftey pin ! be shure to measure it with a micrometer or vernier first !

here are the other 2 filters i used,
the large white brigs and straton one ran the best it flowed quite well and there was only minor 4 stroking when not under any load top end was good but plug showed a little lean at high rpms
the orange brigs and straton one caused a lot of 4 stroking, especialy at the midrange and off idle but was useable in a pinch and the top end was perfect
the new SBP 90 deg filter flows with no restriction i can feel by blowing through it in and out unlike the other 2 where i can feel the restriction with my breath.

i didnt think changing to a high flow filter could warrent sutch a major change in jetting like this but but hey when i cleanned out the carb i found nothing blocking anything and the whole inside was spotless that i could tell. also removed the gasket and though it is over compressed and sort of flat from use, it does not seem to be leaking and i forgot that i used gell lock tight type super glue to seal all around the carb flange and plastic spacer ring so there was no leak there. if there are no leaks and there was nothing in the carb than the main jet must be too small right ?

just incase it was leaking, i am making a new intake gasket anyway out of thick 1.6mm gasket paper, this one will be a lot better port matched to the jug and manifold
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here to stay and compleatly insane ! deal with it lol

Last edited by rogergendron1; 12-31-2013 at 10:12 AM.
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