Spree 44mm bore kits?

[ScooterTweaks]

Granted I have not worked on a Spree particularly just yet, but I have tuned multiple Honda and Yamaha direct drive/cen clutch mopeds and gopeds and found that even a stock motor with a tuned pipe will give good acceleration performance. Different pipes make power at different areas, IE: high end power, low end power.

Higher rpm clutch springs and a tuned pipe with a little re jetting of the carb and maybe oped the air box a bit, will yield amazing results! Mild porting of the stock cylinder will only add to that work. I have to tell you that the mopeds I have tuned were very impressive and all with stock cylinders. We were shooting for cheap HP. I really like using high end goped pipes not the stock pipes because they are designed to work through a wide range of rpm starting very very low. This makes them very ideal for mopeds or the spree that starts off at a low rpm under load at WOT. I have not actually tried any pocket bike pipes but that was because each one I have I got for free, was a stock 2 stroke pocket bike pipe, and is full of crap inside!!! Cut them in half and looked at the insides only to find it is full of packing, baffles, chambers, and not worth the time to cut, chop, gut, and re weld to fit.

A little tuning with what you have has been proven time and time again. Don't get too caught up in "I have to buy this, and have to buy that" bigger is better stuff. I am not saying that bigger isn't more power but am saying that sometimes better flow overcomes bigger cc. I decided after searching for upgrades for my personal Elite SE50 and finding next to nothing I would put this tuning theory to work. Custom pipe, 15mm carb, custom intake manifold, custom reed cage/block, pre-mix fuel, and milled the head for higher compression with a good amount of cylinder porting. Bike does a solid 48mph with a 237lb rider, but does it quick!

BTW, I am not comparing an elite with cvt to a spree with direct drive. Just an example.
I say tune what you have. Pick up a goped pipe for $35-$50 shipped on ebay, a few carb jets to play with (4 sizes or so) and maybe look into a little cylinder porting and spend a few $$$ at the local brake turning shop to see if they would mill down 10-20 thousandths off the head for higher compression.

Good luck tuners!!!