Built my first motored bike! And man, did I learn a lot. I don't have any in-progress pictures, and I built it for my dad's friend. But I basically took a cheap (extremely cheap) cantilever bike he supplied me and put a cheap 48cc 2-stroke kit on it.
I learned a few things: Primarily, nothing on these kits is "plug-n-play" and almost every piece of the kit needed to be modified in some way, as did the actual bicycle.
This particular setup took quite a bit of modifying on my part, as the guy didn't know what kind of bike would work best with the kit (and I didn't either) so I learned as I went.
The bike only had a coaster brake... bad choice, it wouldn't fit through the rear sprocket. I removed it and added a front caliper brake. It also didn't have a straight downtube or top tube, so the gas tank didn't sit flat, and the front motor mount had to be mounted by drilling a hole through the downtube, something I wasn't thrilled to do. The gas tank's outlet hit the frame's cantilever tube, eventually splitting the fuel tubing, and the only way to make it not hit the cantilever was to lean the gas tank to the left of center. Doesn't look bad from a distance, but it looks funny when riding it. I also had to bend the exhaust header to make the muffler fit around the downtube.
After I got it running and driving okay, my only real complaint is the cheap throttle setup. It was all plastic, and the ham-fisted Joe Public who rides it will wind up breaking the twist mechanism, and jamming the actual throttle pin in the carb wide open, making it impossible to start. The throttle also used a plastic pin to keep the whole thing from rotating on the handlebar (using a hole you have to drill) but that lasted about 10 minutes... I wound up having to use a large wood screw through the throttle mount to keep it from twisting.
The owner eventually wanted to install some Wald rear metal baskets to carry stuff in... and I'll say it now, Wald's "universal" baskets SUCK when you try to mount two drive chains, fenders, and baskets all on one set of dropouts. I will never use them again. I had to reassemble the rear axle a half dozen times to make everything fit, and I'm still not happy with it.
The "rag mount" sprocket is very hard to get perfectly centered, I'd highly recommend an ISO disk-brake mounted sprocket instead, by far. It would be worth the $40 they're asking for them on Ebay, in my opinion... it would make the kit quality and smoothness much better, I think.
The ignition module's spark plug wire is very short, making it only mountable on the bike's downtube... and as I mentioned, this bike has a large, curved downtube, so I had to fab a mount for that. Well, okay, I used zip ties... but you get the idea.
My overall thoughts on the Grubee 48cc motor kit:
I learned a few things: Primarily, nothing on these kits is "plug-n-play" and almost every piece of the kit needed to be modified in some way, as did the actual bicycle.
This particular setup took quite a bit of modifying on my part, as the guy didn't know what kind of bike would work best with the kit (and I didn't either) so I learned as I went.
The bike only had a coaster brake... bad choice, it wouldn't fit through the rear sprocket. I removed it and added a front caliper brake. It also didn't have a straight downtube or top tube, so the gas tank didn't sit flat, and the front motor mount had to be mounted by drilling a hole through the downtube, something I wasn't thrilled to do. The gas tank's outlet hit the frame's cantilever tube, eventually splitting the fuel tubing, and the only way to make it not hit the cantilever was to lean the gas tank to the left of center. Doesn't look bad from a distance, but it looks funny when riding it. I also had to bend the exhaust header to make the muffler fit around the downtube.
After I got it running and driving okay, my only real complaint is the cheap throttle setup. It was all plastic, and the ham-fisted Joe Public who rides it will wind up breaking the twist mechanism, and jamming the actual throttle pin in the carb wide open, making it impossible to start. The throttle also used a plastic pin to keep the whole thing from rotating on the handlebar (using a hole you have to drill) but that lasted about 10 minutes... I wound up having to use a large wood screw through the throttle mount to keep it from twisting.
The owner eventually wanted to install some Wald rear metal baskets to carry stuff in... and I'll say it now, Wald's "universal" baskets SUCK when you try to mount two drive chains, fenders, and baskets all on one set of dropouts. I will never use them again. I had to reassemble the rear axle a half dozen times to make everything fit, and I'm still not happy with it.
The "rag mount" sprocket is very hard to get perfectly centered, I'd highly recommend an ISO disk-brake mounted sprocket instead, by far. It would be worth the $40 they're asking for them on Ebay, in my opinion... it would make the kit quality and smoothness much better, I think.
The ignition module's spark plug wire is very short, making it only mountable on the bike's downtube... and as I mentioned, this bike has a large, curved downtube, so I had to fab a mount for that. Well, okay, I used zip ties... but you get the idea.
My overall thoughts on the Grubee 48cc motor kit:
- The throttle setup is horrible. It's 100% plastic, and will not hold up under actual use.
- The engine is very heavy, but runs like a clock... has good power, sounds good, clutch works flawlessly, and is relatively quiet.
- The motor mounts (and indeed the whole kit) is designed for 10-year-old straight-steel-tube diamond frames only, anything else will require fabrication. How many bikes do you see with frames like that nowdays?
- The biscuit sprocket mount works in a bind, but it needs a really solid way to mount the rear sprocket. I'd highly recommend finding a way to do this... the left side drive chain won't run smoothly with the biscuit mount.
- Research ALL the accessories you want on the bike to make sure they fit with the engine kit mounting. Don't guess.
8) Gary
