Ported my 48cc BBR little to no difference in power

[joecass]

So I ported my 48cc BBR engine and I did not noticed much power increase. I was wondering if I have to modify the exhaust and intake because there’s not enough air flow? This is what I did to my cylinder. This is not my cylinder I didn’t take a picture of it but that’s what I did to the transfer ports and I opened up the exhaust port and raised the exhaust port a little also opened up the intake port. Dose anyone know if the carb. And intake and muffler are the same as the 80cc BBR motor? because then I would think that it should have enough air flow to feed a modified 48cc engine if the same intake, carb., exhaust feeds the 66cc engine.

 

[JerboaJohn]

old post I know, but nobody answered ya...
any updates?
I fiddle with my 48cc a bit. if you lose any oomph or see no gain top end, you might've went too far in porting. after you ported it, it needs a richer fuel mix since it's flowing more air, and probably won't have any low end acceleration, but you might get some more top speed and in that thinking, a good expansion pipe like MZ65 will help too, because the stock exhaust & air filter will be restrictive to any gains you made for airflow.
intake for about 1/2 of the 66cc's is wider than our 48's (40mm vs. 32)

 

[LewieBike]

Before you take any advice further, has this bike been ridden the required 300 miles to break in the rings? Secondly my 48 cc engine came with a restriction of the intake manifold gasket between it and the cylinder. Lookd about like a 10mm opening in the gasket, to reduce the fuel air flow, this would hold the engine's power down considerably. I'd pull the carb and intake and take a look at the gasket between the manifold and cylinder before going further

 

[Will'smotobikes19]

Slap an expansion chamber on or a tuned scooter pipe more power for sure.