I have a 70's Sears Free Spirit. i've been contemplating putting a 65cc motor on it and putting around. my only worry is that the wheels and brakes won't be able to handle the speed. (35-40 mph tops) Has anyone done this before, and does anyone have any recomendations? I plan on ordering the motor from www.thatsdax.com . a guy a my work ( a bike shop no less) has this engine but it's mounted on an older Trek 820 so it's a little more sturdy and has a front suspension.

Any recomendations would be lovely.

Eric.


p.s. this is the free spirit.

I think that a little more than a Free Spirit would work for you too. They generally have the cheapest of everything, and (unless this is a German 531) then you should get a better platform, with better brakes. An '80's lightweight from Japan will provide the quality you need to keep your head outta the back of the car in front of you...

cool project, though. Put us up some pics, huh?

my problem is I don't have the money for a motor and a bike... just a motor.. and with the bike already in hand Its hard not to just try it. I really like the idea of using an older cruiser / touring style bike for my platform rather than a mountain bike... even if it means sacraficing a suspension.

If anyone has any ideas where to get a decent, but cheap/ free bike I'll gladly listen.

Those brakes look like alloy parts. probably ok. the pressed steel ones are less good. repack all your bearings and lube all your cables and inspect things thuroughly. are those the origional tires? look really closely at them too.

You got the bike, then you're the motor. Pedaling is cheap, what it burns up in food will be paid back in lower medical bills.

If you put a 65cc engine in a Free Spirt I see some big medical bills in your future. Those bikes are barley capable of their intended use.

Enjoy your wobbles.

4 stroke is nice for emissions.

way cool. I want to put one on a westcoast chopper or an orange county stingray.

They are the original tires, but they're dry rotted. Since I work at a bike shop, I plan to use my employee discount to get some tires on the cheap.

also, I'm hoping I can find a bike/ components there so I don't have to break my ass with the engine on the free spirit. lol

Again, if anyone knows of someone getting rid of a mountan style bike or frame in south east michigan, please let me know.

that may work out, as an experiment. Does that bike have a rear coaster brake? If not get a back one before you try to go fast with the motor. And post some pictures. Emergency room pics get extra credit.

That bike is a Murray and built fairly strong.65cc is a lot of motor---35cc would do a bit better on a no front suspension.and speeds about 20mph.Bicycle wheels tend to collaspse all of a sudden not a little at a time.Your only shock is the tire on that bike.Why go 35-40 on a bicycle when you can do 70-80 on a motorcycle.

Bike engine = legs

That it isn't. It's a Westfield/Columbia, without any doubt. L-shaped dropouts, characteristic fork crown, typical seatstay joint at the seattube, unique headset races, etc.

Wouldn't suggest this guy for motorization. Never had a Columbia BB or headset that fit quite perfectly here - races commonly too loose in the frame. Enough that the vibration of the motor may cause some odd loosening of components now and then. Columbia frames themselves are whippy in the first place, even men's diamond-framed models - she'll start wobbling out from under you by the time you hit 19mph.

Dig up a Raleigh Sports - although Raleigh did some absolutely lousy lugged-frame brazing by the late '60s, most of them will be far superior to this little number. Leave the Free Spirit for leisurely rides around the neighborhood...

-Kurt

Yup. The best two-stroker ever made.