Planning a MotoredCommuter - Any Ideas?

[Yoda Bob]

Continuation of a discussion I began in my intro, here:

http://www.motoredbikes.com/showthread.php?t=27151

Thanks to SimpleSimon, Happy Valley, give me vtec, professor, and Alaskavan for your prompt and well-thought advice. After soaking on your comments a couple days, I believe I've come up with something that makes a lot more sense.

Instead of the powered long-tail concept I started out with, I'm thinking of putting the stock GEBE setup on an back-end of my old Giant mountain bike and installing a large cargo rack on the front. This solution provides a number of benefits:

Strength: I've found over the years that a shorter, stiffer rear triangle better copes with the torque loads imposed by the drive train.

Weight Distribution: Heavy loads on the back of the bike stress the rear wheel and create wierd handling characteristics.

Handling: The old Giant is by far the most comfortable of my potential donors. Moving the cargo weight forward will only improve its stability.

Cost: Adopting this "minimalist" approach creates potential cost savings in many component selections.

Here's how I see it so far:

Stock Giant Rincon frame
Stock cantilever brakes at both ends
Stock 36-spoke front wheel
GEBE Eagle / Velocity 36-spoke 14-GA rear wheel
Tires - Schwalbe Speed Cruiser HS 321 26 X 1.50 street slicks
Front cargo rack w/basket or milk crate
Fork leg "low-rider" pannier mounts and water-proof panniers
Planet Bike fenders
Dual-headlamps (incandescent) forward, hi-intensity LED flasher/tail light

Motor: No longer sold on contructing a two-wheeled freight truck, I'm re-thinking the 35cc power unit specification I submitted in my initial posting. Maybe I can make do with less.

Would a smaller motor (such as the 25cc Robin/Subaru) have enough grunt to propel me, the bike, and my gear (approximately 300 lbs.) up the mile-or-so 10% grade at the end of my commute? What if I helped?

With gearing suitable for my worst-case climb, could I hope to maintain average speeds of 15-20 MPH over the flat to rolling terrain found on the rest of my route?

Would appreciate your feedback on any and all design considerations, but particularly with the powertrain (as I have zero experience with them).

Thanks!

Yoda

PS - Almost forgot: I've got my heart set on the front rack pictured below, but have not been able to identify the manufacturer nor locate a U.S. domestic source. Is anyone familiar with this piece?

 

[Alaskavan]

I have no idea about that rack. And, I haven't heard anything about the R/S 25. I hear the R/S 35 is bullet-proof. How much $ would you save going to the 25? I'm not sure about carrying the weight on the front. I prefer a trailer.

 

[give me vtec]

excellent choice.... the good thing about the gebe setup is you can put it on almost any bike and it will last for years. So if you do decide to go with another bike you can swap it straight on the new bike as long as it has the correct # of spokes. I suggest buying a couple of different gears from golden eagle and experiment with them. They are pretty cheap and VERY easy to swap out. The smaller gears are ideal for towing.

The rs eho35 is bulletproof... I have three. I wouldn't go with anything less than the 35 because of lack of torque.

 

[Yoda Bob]

Thanks, Alaskavan-

According to GEBE web-site, pricing is a wash between the R/S 25 and 35. The 25cc is a couple pounds lighter, it's quieter (?), and gets better mileage. Might be easier to camoflage.

I'll be carrying only about 20 lbs. of gear on a regular basis. Hanging it over the front wheel may improve cornering grip and dampen twitch. I'm interested to find out!

 

[Yoda Bob]

And. thank you - gmv

There's no substitute for cubic inches!

There's a lot to be said for bullet-proof, as well. R/S 35 it is.

 

[SimpleSimon]

I've been out of pocket most of the last couple of days, so I'm late. I concur as regards the R/S 35 over the 25 - the power differential is not large, but the low end torque differential ought to be. Which is what you need for that long climb.

The Giant Rincon is a great frame, sturdy and well designed. Good choice - just get a "Big Man's Saddle" for it for regular commuting. A suspension seat post might be a good addition as well.

As regards the pictured front rack, I can't find it either (and I'm kinda infamous in some circles for my Google-fu). I'd just go to Home Depot, buy some 1/2 inch electrical conduit, a hacksaw, and a sacrificial 1/4 inch steel drilling bit, plus some stove bolts, washers, and lock washers, and make my own. Hint: once the two primary U's are bent to size and the ends flattened/drilled, cut your crossbars to length, flatten the ends,and don't worry about welding them. Just use a cut-off wheel in a Dremel tool to slot the frame tube appropriately, insert the flattened tabs of the crosspieces, J-B weld them and bolt it together. Even the mounting tabs could be L brackets done the same way.

If you have a welder or a good brazing torch, use it instead.

 

[Yoda Bob]

Excellent advice about the saddle and rack, SS. I may have already found the industrial-duty rack of my dreams, an "ambush" ebay bid might find it on my doorstep cheaper than I could build it for. A cushy saddle is definitely on the list.

Like you, I've nothing but praise for the Rincon and am looking forward to riding it again. I logged several thousand miles on the bike way back when. It's smooth and stable: no surprises. No MTB I've ever ridden fits me better.

I recently got back in the saddle after a very lo-o-ong break. I went out to the shed to dust off the Rincon, and it was gone. I was very sad.

Determined to ride, I turned to craigslist and found another bike. It's a very good bike: a much more modern and sophisticated machine. Unfortunately, it's twitchy, unyielding, and mean spirited; unforgiving in every conceiveable way. It requires constant attention to point straight and the stiff frame beats me to death.

I was telling my daughter about the new bike and how much I missed the Rincon, when she reminded me I'd loaned it her husband a while back... duh! I was overjoyed and rushed to their house to retrieve it.

Looks like it spent a good deal of time outside. Everything steel is rusted. The spokes, cables, saddle, and tires are all shot. It'll require a good deal of time and effort to restore.

I'll tear it down next weekend to begin the restoration. Parts of the frame will need taking down to bare metal to get rid of the rust. After rust treatment and prime coating: a stove-black rattle can paint job, a couple of MBc frame stickers, and a satin clearcoat ought to give it the classy look it deserves.

This build is gonna take a little time. I'm presently enjoying the life of an unemployed college student. Money is often scarce.

The entire build will be financed using money I'd otherwise spend on gasoline, having committed to commuting using the bike and bus routine.

I project a completion date in mid-October. I'll post again as the project begins to move forward.

Thanks, again, to all!

Yoda

 

[Happy Valley]

Yeah just catching up here with the thread too yoda. How ya doing?
Hmmm, dang I thought we'd be going on about cargo bikes and longtails.
Kinda my special interest. http://alttransbikes.blogspot.com/

Your plan sounds good, since you already have the Giant. Lawd knows I like EHO35s, got a bunch. One thing though that caught my attention was that mile long 10% grade!!! Toting 300# I would think you will need to be doing some pretty good pedaling on that. Maybe you expect to so no biggie, lots of guys though think their getting a trail bike something.....we're talking 35 ccs.

Racks: looks like something this guy does maybe--
http://cetmacargo.com/index.html

pricey though???
then there's always DIY:
http://www.instructables.com/id/CETMA-Style-Bolt-Together-Front-Bike-Rack/

 

[Yoda Bob]

Glad you chimed in, Happy!

I must admit to being intrigued by the longtail cargo bike concept. I'm not sure how practical they actually are, but they look so cool! I hope there's one in my future and will do all I can to justify owning one once I get back on my feet.

Biggest apparent advantages include the conventional cockpit layout (okay, I'm a bit of a purist), heel clearance (w/panniers), stability, visibility, and weight distribution.

I have reservations about the length of the pedal-driven drive train, flex, and the potential for metal fatigue in the long, whippy frames.

Given the sheer mass of these machines and the loads they are intended to bear, I feel they're perfect candidates for motorization. Having recently stumbled upon the Surly Big Dummy, I thought of it immediately when introduced to motored bikes. It seems a natural.

I viewed the Alt.Trans link in your post. Great Stuff! A couple of frames there appear to have openings within (the Xtravois) or above (Surly) ideal for placement of a power unit attaching to a GEBE-style toothed-belt drive. In both cases, the power plant could be installed below the plane of the cargo deck, very close to the bikes' centerline, and forward of side-mounted luggage, racks. or baskets.

Added Bonus: The motor might also, in some jurisdictions, be easily concealed by fairing-in or hiding beneath the luggage.

It's all good stuff that I hope, some day, to revisit.

Meanwhile, my budget build...

Thanks also for the links for the CETMA racks. I've studied these quite a bit and will figure out how to get one. Period.

I'll buy American as much as possible. Buying local is even better. These racks are currently being built in the Pacific NW. Can't get much more local than that!

Lights out for Yoda... sweet MB dreams!

 

[Happy Valley]

Alrighty then, good stuff.

Missed your reply to SS the first time around. The Rincon frames IIRC from about 2000 went to Alum, prior they were Chromoly. Not sure what year ya got but if it's steel, a good idea is treat the inside tubing with rust inhibitor. Boiled linseed and 30 wt. motor oil mixed 1:1 is as good as any of the spendy pre-mades.

I've seen, ridden and worked on a lot of longtails. Also, though I personally am not crazy about Xtracycles, I do know a number of folks doing some serious touring and can't think of anyone complained about them being soft.

You might know these but food for thought in the very DIY mode:
http://worldbike.org/our-work-two

best