Happy Saturday Afternoon!

svejkovat

Member
Local time
5:44 PM
Joined
May 16, 2009
Messages
30
Thanks for the forum!

I live in Michigan and have a couple of Puch mopeds that I love. I've spent 20 years riding BMW motorcycles and about five years ago a family friend gave me his Puch when he turned 70. It sat in my garage for a year before I got the nerve to ride it in public. I was amazed at how many more positive comments I got than negative (no negatives at all).

I got a second Puch (first was a two speed and second was single) and since then have ridden them far more often than my BMW 650. It just makes two wheels more fun again, like when we were kids. And the fun never seems to get stale for some reason.

Anyway, I've often looked at my 26cc Ryobi four cycle trimmer hanging in the garage next to my mountain bike and gotten dangerous ideas. The Puchs have never really been 'mopeds' in any honest sense. Out of gas, you quickly discover that it's easier to push the **** things than to pedal home. The pedals are there to start the engine and, more importantly since they might just as well have hung a kickstart off the side of the motor, to legally qualify as a 'moped' for road use. Hmm.

With that in mind, I'd like to aim at the 'best of both worlds'. Pedaling as primary power, 26cc 4 stroke as supplement to add comfort, speed, and range.

So I have a shop in the basement with a tig welder and lathe. I have a little 4 cycle engine. I just never got up the nerve to hack into my nice mountain bike, and that's a good excuse not to get "into" it. So last week I find myself at the local scrap metals yard looking for some perforated steel for a project and a truck pulls up with about three dozen bicycles tagged from the sheriffs dept - "stolen/unclaimed". Wow. Most were junk, but one was a dark gray Specialized Hardrock HRXC in great shape with enormous diameter aluminum tubing and way oversized tig welded joinery and lugs. The front shocks are actually twice as rigid and beefy as my Puch's. The entire bike weighs less than 1/4 of the Puch.

I sauntered over the booth and as casually as possible asked how much for any of the bike frames "over in that pile". The too busy scale operator, without even looking at me yelled 10 bucks each.. cash! ****! I have no more excuses. Into the pickup bed it went. Sorry Ryobi.. yer weed trimmin' days are thru.

After a day of websearch for small gear reduction boxes of appropriate size for this project, I found this webpage
http://www.electricycle.com/
and decided that this might be the most appropriate means of getting this motor to the back wheel. I don't know. I'm pretty new at this, but am really going to research it before I begin. The Ryobi puts out considerably less torque than this guys electric so I imagine I could use a less robust belt and jackshaft. I'd also like to see about using the original drivetrain and gear shifting!

Among the videos on youtube is one where a guy connected a honda trimmer (but a huge one) to his bike via the original drivetrain. He used the standard handlebar shiftset. Very cool. But his motor hangs off the side of the pedal crank! I want to use the pedals along with the motor.

First off, I'll stress that the motor need not be powerful.... and this one clearly is not. An extra two inches of 'string' spooled out will bog it down. But it does qualify as extremely lightweight, efficient, and quiet! I really don't anticipate using it alone, without pedaling. Being low powered, I don't believe that injecting it into the original drivetrain would pose a problem; my legs probably produce a bit more torque than this is capable of.

I tried a couple of searches but did not find a good way to locate any discussion here in the direction of using the original drivetrain. At first glance, I imagine it driving a sproket on the left hand side of the pedal crank, ideally a 'freewheel' sproket that engages in an opposite direction of a standard freewheel. From there, it's "simply" a matter of very compactly reducing the ratios from the 26cc motor to this sproket.

I looked through most of the photo section and did not see this arragement. Has it been discussed?
 
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Whew! Your intro wore me out. :D
You sure you're 87 or is that a typo?

Welcome to MBc!

Short answer: Yes, a lot, on all the topics you mentioned. Spend a little time reading and you'll begin to sort through to key words that produce search results you're looking for.

BTW, I remember seeing that Ebike project page awhile back, very impressive.
Sounds like you'll fit in here very well. Formulate all your questions and post'em up in the appropriate forums, I'm sure you'll get a lot of detailed feedback.
 
Ah, no. I'm hoping my nick might suggest that I approach authority with a protective sense of absurdity. When asked any person information at all, I perfer to lie.

Otherwise I'm perfectly honest!
 
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