Hi,
I have an A55 Tomos Streetmate, 2005 and would like to get a little more power out of it by dremeling the transfer ports.
Has anyone done this with an A-55? Suggestions?
Thanks,
Hi,
I have an A55 Tomos Streetmate, 2005 and would like to get a little more power out of it by dremeling the transfer ports.
Has anyone done this with an A-55? Suggestions?
Thanks,
Hah, DON'T start by dremeling transfers. They're plenty big for 50cc, and it's easy to ruin stuff that way.
Widen the exhaust and intake before you do anything else, you'll see bigger gains. You could probably also get away with raising your exhaust 1mm or so, and lowering your intake 1mm or so. Be careful, and take it slow.
Have you done any other tuning already? If its all stock the cylinder isn't where your lack of power is coming from. Do you still have the stock pipe?
Looking at his profile, I figured he was talking about his Streetmate with the A55, and that's at least got a pipe on it.. Even with the stock carb, it'd probably respond pretty well to porting
Cut the exhaust up 2.7mm, widen it to 24mm and in an oval shape. Cut the intake down 3.7mm and widen to 26.4mm and you can do it in more of a square shape. Leave the opening round for the intake though, and make it smooth from the opening to the square part on the piston side. Cut the top of the piston dome down 1.8mm on each side, this opens the transfers up earlier. Buy a 50cc hi hi comp Puch head and bolt it on. This sets your timings up to around 155 exhaust, 140 intake, 115 transfers. Run the stock carb with a UNI pod filter, 72-76 main, 35 idle, 210 diffuser and set the needle second from top. You'll be good then.
For comparison, stock timing on an A55 is 140 exhaust, 100 transfers, and 120 intake. Also it might be hard to cut 3.7 mm down on the intake side, so you can also just cut the piston skirt up on the intake side. Cut the intake port down as low as you can manage to do, then cut the difference out of the piston skirt. You can do all of this pretty easy with dremel bits and some time. Nothing crazy, just measure and you will be fine. But measure often, going to far makes it hard to come back.
Oh also you will notice the cases are ported larger than the bottom of the cylinder, so make them match of course. This setup will be better than buying the Airsal kit, and way less vibration.
Jesses,
You've just made a friend for life!
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