Choosing a Motor...HELP!



I need to buy a motorized bike to me get to school, I've been on many sites eg: ebay, bikemoters ect ect, and all I get is a mass of competing claims, and statements that seem to be greatly exaggerated.

My needs are very simple: I need a bike kit preferably a 50cc (maybe 70cc) because it's very hilly where I live, 4 stoked, rear mounted- i don't want a running motor between my leg's because it feels not very nice, and i have a mountain bike with full suspension. And Chain or belt driven.

After scouring the internet for many hours and after long and tedious debates with me myself and i I have found 3 reasonable engine kits, I have listed them below with my comments/questions for each of them. They are in no particular order.

Any comments, suggestions, answers and/or constructive criticisms are welcome.

1) It has a Reliable Honda Motor as opposed to some shady Chinese motor, but the cost is WAY over the top. I mean the engine itself should cost no more than $300. So subtract that from the total cost and I'm paying $450 for some shingles, nuts, and bolts??!!

2) No 2 is the grubee Skyhawk WS stage II 4 cycle kit rear mt. The motor is Chinese but the price should be MUCH cheaper. The only thing is grubee only does wholsale, and i have yet to find a seller that sells the grubee skyhawk rear mount engine kit. Any who knows were i can find a seller that sells the above mentioned engine kit please tell me.

3) I don't even know if this thing what stroke, or is it even rear mountable, I've already written the vendor an e-mail asking him clarify the specs on the motor. BTW the website also sells the same motor but this time with a dry clutch. What's the diffrence between a dry clutch and a oil bath clutch? A simple answer of pros and cons will do, I'm no mechanical guru.

There you have it my 3 choices, I'm hoping to get the motor before Halloween, and Christmas shopping season.

Please help decide for I'am very Confus-ed

1) Also included with this kit is the gearbox, and don't forget you also pay for research and development! This kit is expensive, but from what I have READ in Rack'Em up. This is the Cadillac of motored bikes!
2) ?????
3) this one is a happy times frame mount, 2 stroke and will not go on a rack without serious mods.

Again for the ??? time. If you want a rack mount your answers will come from Rack'Em up! but please do not repeat this as a new post in that forum. Read what looks like it might work for you and post your questions in that thread.
pay attention to the moderators, they're trying to help it's time for you to help yourself a bit.

read the forums, everything you're asking is answered.
I agree with 5-7. Unless you're carrying a Lot of heavy books, and quite a bit of weight yourself, and going up some steep hills (like the Rockies), you probably don't need the big Honda.
Yeah, I thought the 49cc 4 stroke Grubee rear mount would be quite suitable, possibly smaller and A LOT cheaper, the only problem is i can't find a distributor that sells it.

Anyone know where i can find one?

BTW I checked ALL the posts with "Grubee" in them and non of them carry the response that i want.


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That GX motor is....

The GX motor is good for sure. Placing it over the rear tire is never a good idea. Putting such weight so high and to the rear and over the tire will make handling very poor indeed. Also.. The bike in your picture is a rear suspension bike. That means, the motor is sprung weight. This is really really bad news. This will make the rear suspension worth less shake the motor constantly. To reciprocate such a mass is a bad idea. The best bet for a rear mounted engine is for a bike with no rear suspension and a bike where the motor can NOT be mounted between your legs, such as a recumbent. The only thing worse than putting an engine over the rear wheel is putting a motor over the front wheel. The best place for a motor on a bike is always low and center. Laws of physics applies. Enjoy the ride...