Here are two reviews of the small and the medium sized GEBE engines, note that the Popular Mechanics is 2004, so there have been about 4 or 5 changes in the belt, belt strength, gears, drive shafts. But all and all, what Pop Mechanics has described is about the same as I have experienced.
THERE IS ONE BIG CAUTION with GEBE systems, and really it might be a theft deterrent.
I have found, with the smaller engines especially, that sometime during the breaking in, the engine/bike and belt accustom themselves to the riding habits of a single rider, who knows what the noises/hiccups mean, and reacts accordingly.
If the spokering was not installed centered (which holds the tension arm steady) AND a stranger gets on board without experience or an accompaning rider, there is a high probability he/she may damage the belt.
I have had belts in perfect shape, with a thousand miles on them, and a novice can shred it on a medium incline.
I will add that between the two systems, I think the GEBE is the easier to deal with, however.
Easier to install, lighter, and easy to adjust, but as noted above, some might not be for those who think they can just get on and gun. That is not what they were intended to do, even though with the larger motors, they fly around quite well.
Well, I don't gun because it's understood the clutch shoes will wear out faster, just like riding the breaks. I take it easy starting out but acceleration is crisp anyway if I want that. It's superior to a friction drive or some gear reduction system that loses 20-30 percent energy before it gets to the hub. Even a chain drive is heavier and creates more friction than a belt, correct me if I am wrong.
If you are a heavy person, expect a lot of spoke breakage from either kit, (although it is not uncommon for lighter personnel to have the same problem). It is often necessary to order a rear wheel with at least 12 guage spokes, (which can't be replaced if they break), or get a good rim, and hub, and have the wheel custom built with 10 guage spokes by "The Wheelmaster" in Auburn, WA, (if one breaks the wheel is guaranteed for life, and the broken spoke will be replaced). I did the latter of the two, and haven't regretted it even slightly, because I haven't had any problem with spokes since. Also you might read about using epoxy cement to keep your drive ring centered, (GEBE), or wrapping wire with solder, or plastic tie wraps where your spokes cross to make the wheel stronger. In my opinion if such drastic measures are necessary to keep the integrity of the wheel/drivering, then much thicker spokes are needed. Needless to say, I don't need to use "field expediency" measures to hold my rear end together...lmao. Love those big 'ol 10 guage spokes!! he he.
Here is my take on this. I only have 820 miles on my GEBE R/S35 Belt drive though I did have a whizzer in 1949. First, because I read this web site and checked many bikes before I bought anything, I ended up with an easy, quick install. So far absolutely no problems. There is no sign of wear at all. I ordered the solid axle and am still using the original belt, nobby tires and original wheels. I expect this system will go a very many more miles and this is the reason. I change oil often, I keep things tight, I pedal to 5/10 mph, then advance the throttle easy. I pedal on hills that I could go up without pedaling. I weigh 200 lbs and have a heavy bike (Schwinn Aerostar). You must realize that no matter what you do to your bike that you are still riding a BIKE. The engine is only to assist YOU. I will not ride faster than road conditions allow and obey all traffic laws. If you ride with respect toward others you will ride and live longer. You ask which kit is better. They are all good if you pay attention to the installation, treat the bike and engine good and use common sense while riding. Do that and you will no doubt have many enjoyable hours and miles ahead of you. You will see on this site many people that want to push everything to the limit. They are having fun, love to work on their bikes and know they will wear them out quicker and replace parts more often than a cream puff like me. I'll be 72 next month. Can you guess why I'm still riding and enjoying myself on the streets and back roads? That said, I may get a larger engine! Why? For more power on the mountains when I want to carry a heavier load. NOT for speed! I will still pedal to start out and will pedal as much as my tired old bones will allow on the hills. If you want to ride off of ski jumps and do double flips over a row of cars with a 200cc engine disguised as a milk crate, thats great! Enjoy yourself to the utmost! If you want to enjoy the scenery, old age and keep your bike awhile, then do it my way. Treat your wife, girlfriends and bikes (not necessarily in that order) with respect and see if it won't pay off! KenSpice
For weight and simplicity the GEBE looks good provided you stay about 35cc.
For power the Staton chain drive is the way to go, as they offer you up to 50cc / 2.5 HP. Staton will handle the power, I'm running 4.2 HP, however, it cost more and is heaver.
I would not rule out a quality friction drive. Your power would be limited to about 2 - 2.2 HP but they are less costly and very light and simple. The biggest limitation is wet roads. I don't mean riding in the rain, I mean any moisture on the road. If you can see moisture on the tire your gonna slip under load.
They all have their good and weak points, no one size fits all solution. The more research you do, the more you're gonna be grin'n while go'n down the road.