Devil's Advocate
New Member
Hi all, I found this place when looking for ways to improve performance on a 48cc motor. I have not ridden a bicycle since I was a kid but recently picked up a pre-fab motorized bike from a guy who builds them. It's a $90 supermarket mountain bike with a 48cc 2 stroke motor that has been de-tuned to 200w to comply with Australian laws.
It's been a learning curve for me just getting used to riding a bike again, let alone a motor powered one. I find the cars very daunting and can never hear them coming up behind me because of the exhaust noise. I've realized that becoming traffic savvy on a bike is an art in itself, motor or no motor. Fortunately in my area there are several miles of trails and tracks that cut through to all of the major parts of the region, i'm utilizing them almost 100% of the time, and only venturing into traffic when I have no other option. I've done about 30 miles in total so far, and really like it as a mode of transport, I just wish there were more bike lanes on the roads.
The bike itself is okay for it's limited 200 watts I suppose, but it really struggles up hills and requires pedal assistance big time. I weigh 110kg (230lbs), so i'm really up against it. The manual says that the engine will increase in torque as it is run in, but I feel that I'm going to want more. The company that builds the engine can provide an upgrade kit which de-restricts the engine and gives it the power of a regular 48cc, but this would make it illegal to use.
Rather than buy the upgrade kit (which appeared to be just an exhaust pipe and a carburetor) I was wondering what I could try on the existing combination to improve the torque and a little bit of top speed? The guy I purchased the bike from showed me a 200w inlet manifold gasket and it had a hole in it about a half or even maybe a third of the size of the carby and manifold throat, if I replace this with a gasket with a larger opening, will I gain power? I suspect that the exhaust might also just have a restrictor plate in it, and if I removed that as well, would I theoretically see an increase in torque or power, and is it likely that could I adjust my existing carby to work with the better breathing capability?
Sorry to bombard you with so many questions, and I hope i'm posting in the correct forum.
It's been a learning curve for me just getting used to riding a bike again, let alone a motor powered one. I find the cars very daunting and can never hear them coming up behind me because of the exhaust noise. I've realized that becoming traffic savvy on a bike is an art in itself, motor or no motor. Fortunately in my area there are several miles of trails and tracks that cut through to all of the major parts of the region, i'm utilizing them almost 100% of the time, and only venturing into traffic when I have no other option. I've done about 30 miles in total so far, and really like it as a mode of transport, I just wish there were more bike lanes on the roads.
The bike itself is okay for it's limited 200 watts I suppose, but it really struggles up hills and requires pedal assistance big time. I weigh 110kg (230lbs), so i'm really up against it. The manual says that the engine will increase in torque as it is run in, but I feel that I'm going to want more. The company that builds the engine can provide an upgrade kit which de-restricts the engine and gives it the power of a regular 48cc, but this would make it illegal to use.
Rather than buy the upgrade kit (which appeared to be just an exhaust pipe and a carburetor) I was wondering what I could try on the existing combination to improve the torque and a little bit of top speed? The guy I purchased the bike from showed me a 200w inlet manifold gasket and it had a hole in it about a half or even maybe a third of the size of the carby and manifold throat, if I replace this with a gasket with a larger opening, will I gain power? I suspect that the exhaust might also just have a restrictor plate in it, and if I removed that as well, would I theoretically see an increase in torque or power, and is it likely that could I adjust my existing carby to work with the better breathing capability?
Sorry to bombard you with so many questions, and I hope i'm posting in the correct forum.