Don't let this thread die :)
I have a long history of working on cars, so have a background of sorts.carb, points, no problem.
i was given a 75 eureka flex basket case, 880 miles total rust from sitting, nothing to lose.
6 kids so budget is first priority.
research: tons of stuff to read and digest
http://www.mopedriders.org/html/manuals/garelli/csm/garellicsm.htm is a good starting point. should be everything to get you cruising down the road
http://www.mopedarmy.com/resources/articles/fredsguide/ was useful to me for the plug chop, one of the only ways i know of besides general feel to gauge performance. no dyno, forget the 4 gas.
without 6 carbs to swap out, or even a mixture needle on the sha, i'm going to shim the head with a smaller head gasket to increase the compression ratio from the stock 7:1, should increase torque without pooching the air fuel mix.
2mm gasket, i'm going to try a .5mm if there is plug clearance (plastigage helps)
not badmouthing online stores, but finding a good shop in the area and paying the little bit extra for the 1 on 1 service sounds worth the money.
my wish plan:
adjustable carb, 15mm throttle (brand suggestions for adjustability?)
gears, the tool for pulling the flywheel is req. for the front.
ehaust, no idea what is going on there, factory restriction, carbon buildup?
between each mod i plan to ride ALOT to see what i've done
not a lot of intial outlay of cash, plenty of time for feedback/research, hopefully no damage to the motor.
truth, post back if you find a mid size carb. and i might find the money and we can compare notes.
the flywheel puller tool :
http://www.themopedjunkyard.com/supplypage.html
on a side note: i removed the stock airbox (yours is on in the pix) removed the wire screens in the throttle bore, and installed some gauze with k&n filter oil between the layers
neutral rev. proves top rpm is restricted by installing the box.