Frame Fitting for Engine Mount

[brujahboy2004]

Hey my name is Brandon, I just joined the forum today, and though I don't have a motorized bike just yet, I am going to be purchasing a kit very soon.
I felt it would be a smart move to be able to bounce ideas around with a group of people who have experience with the field. I don't think I'm too ignorant when it comes to basic mechanics, but I'm not exactly "savvy" either.

I guess my first inquiry would be about the frame I'll be using. I own a 26" Schwinn Sidewinder mountain bike (S2600WMG) that I will be using as a donor bike. It has a pretty robust frame for a dept. store bike, which was the second factor in my purchase (after budget). I heard horror stories about frames coming apart and people getting seriously injured, so I made sure to check all of the joints and welds for bubbles, gaps, evenness, etc. The dimensions on the inside edge of the tubes measures out:

Seat Tube - 13 1/2"

Top Tube - 19"

Down Tube - 22 1/2"

I've printed out a template to make sure that it would fit in the frame, and though it's a bit snug, it should fit.
The only thing that concerns me is that the down tube is a very thick (55mm or 2 3/16") and is an oval type shape. I'm sure there would be a way to modify it, although I'm leaning more toward a build that doesn't require altering the frame (drilling, cutting etc.) I've seen people use muffler clamps to secure the engine, and was wondering if something similar would work for me even if the tube is over twice the size intended for the engine (it's a fat boy! lol.) Please let me know what you think would be the best plan in transforming my bike into my new toy! Thanks.

Also, I've been seeing a whole lot of debate on which motor kit is the best to go with. I'm not so much concerned with speed as I am reliability and a quality product (there are plenty of upgrades to heighten my performance if need be). I just want to see if I can obtain a well made kit "out of the box", so to speak (all machines need maintenance and tuning) so that it makes it a bit less difficult, and frustrating ,to maintain in the first place.

 

[Lunardog]

Let me forewarn you on the sidewinder. Check my profile and picture album. The sidewinder does seem to be a well constructed bike. Steel frame and shimano gearing but it presents some semi-serious mods to get a 2 stroke to fit. If you decide to go this route anyhow I may be able to assist you in some of the roadblocks you may encounter. Good luck and motor safely.

 

[brujahboy2004]

Thank you very much! I was worried that it would be a major pain to get the engine to fit in the frame. Looks like one heck of a project. Kudos on a great job! I actually ended up opting to go for a rear mount anyway. I was thinking along the lines of something I could easily disassemble and adapt for another bike, without much modification, if I were to encounter any difficulties. I'm trying to steer away from Grubee, but budget is also a concern. I'm seriously looking at the 49cc 4 stroke available on livefastmotors.com. Thank you for your input! I'll be getting my kit and putting it together in approximately a month. I'll post pictures and let everyone know how it went! Thanks again!