my new adventure

motothrills

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Apr 29, 2018
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Old guy here having years of experience with both bicycles and motorcycles but I am entirely new to motorized bicycles, as my new adventure. Basically, I am in the low speed camp, not interested in seeing how fast I could get a bicycle to go. In the region where I live there are smaller rivers running north to south with several miles of distance between the rivers and the roads following alongside those rivers tend to not have any notable hills but the east and west roads include some big hills in between those rivers and so a bicycle having a small engine needs to be geared down for the torque needed to climb those hills. Plus, I plan to include a pair of wire baskets on the back of the bike for grocery shopping trips, so the bicycle I am working on could be considered to be a two wheeled SUV. With the right gearing, a Honda GX35 engine seems just about right.
 

curtisfox

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Dec 29, 2008
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Welcome aboard !
Yes 4 stroke is the best for torque, and can gain some by a longer intake. What state are you in? Most states allow 50 cc motors. Study board tracker and DIY sections and learn more, good luck ..........Curt
 

motothrills

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Apr 29, 2018
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Hi and thanks for the welcome! I am in the state of Connecticut, New England, which allows bicycle engines of less than 50cc. At first I was looking at 48 and 49 cc 4-stroke engines but discovered that 35 cc engines could suffice provided they get connected to the right gearing and a rider is willing to contribute some pedaling effort. I can work with the lower gearing because I am not in any particular hurry to get anywhere and I look forward to the exercise gained by doing some pedaling. Anyway, a 35 cc engine seems like a challenging but good place to begin. Yes, I even considered a 25 cc engine but that seems just too extreme.

Another thought, smaller engines and slower speeds could amount to a safety factor. A car driver seeing a bicycle on the road might reflexively expect the bicycle to be traveling at, well, typical bicycle speeds and then could just as reflexively pass the bicycle accordingly. But if a motorized bicycle is actually traveling considerably faster than typical then a car driver might become momentarily confused, possibly resulting in an accident. Anyway, that is just a guess on my part.
 

curtisfox

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Dec 29, 2008
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motothrills

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Apr 29, 2018
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I could go either way, 35 cc or 49 cc. They both work. But I prefer to avoid "package" deals including all necessary components, for a few different reasons. Besides, part of the fun of this project is in designing it. Fortunately I am not in a hurry.
 

curtisfox

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Dec 29, 2008
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I am with you as i make all my own parts, and already have a bunch of parts stashed through the years. Also have a bunch of engines, old Briggs, Lauson. I built a bike back in the 50's when i was 15 back when there was no kits. LOL
I am working on and building the hole bike now, but is taking forever, sorta why i suggested a kit. You could sell it after you get yours built,
Best of luck with your build...........Curt
 

motothrills

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Apr 29, 2018
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Hehehe! Having a bike to ride, any bike, to ride along on with all of the adjustments, maintenance and repairs needed to keep one running, would not leave me with enough time and energy to design and construct a second bike, so while I do appreciate your suggestion of putting a "package" kit together as a proven way to save money and to get on the road sooner, I feel certain that I will eventually get more satisfaction by putting a bike together which looks and works just the way I would like it to. Yes, the kits do have their advantages, thank you, but the more I am now learning about the details of what it takes to make a motorized bicycle successful, the more reasons I can now find to do some things a bit differently, or at least to complete a bike which in ways would be unlike any bike currently available in kit form.

Then again, there is an old saying, that there comes a time to fire the engineer and to simply get the job done.
 

curtisfox

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Dec 29, 2008
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Fire the engineer. LOL. Having a bike to ride, i have pedal bike, will be 77 in Oct. so it keeps me going. I had a Monark twin when i was a kid, belt drive, a lot like a Whizzer but with twin engine. So i am kind of stuck on belt drive, my current build uses a 24" bike rim for belt drive pulley. Be what Mr. B did on his build. https://motorbicycling.com/threads/excalibur-09.37011/ it is easy to get good gear right from the start, about 6.6 to 1, easy to get the rest up front from the engine. Read Mr.B's build, may help you with some ideas.

Maybe i should fire my engineer...........Curt