Thinking Outside The Box- I mean Frame

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cannonball2

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Oct 28, 2010
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Colonial Coast USA.
I'm for sure not the first person to do this. I needed a home for the new Grubee I just got and this bike was sitting waiting on an E conversion kit I have. So it got tapped to run the Grubee. May be an E bike later.

Fabbed a set of bolt on mounts. Was going to weld to the frame but figured
the tubing was thin and would eventually fail.

Its roughed out now waiting on the rear sprocket to set the chain line before welding the mounts together. I will have to ditch the rear disc which I hate doing but its the only way to make this work that I can see. The front will stop it fine and the tire has enough bite to handle front only braking. This wont be a terribly fast bike anyway.
Carb just clears the frame. Pedal clears the engine just fine. I imagine it will take an idler on the wrong side of the chain to clear the frame.

So far so good.
 

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Ludwig II

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Jul 17, 2012
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You have brought to mind things like the French cyclemotor, the Vap 4, which were mounted close to the back wheel.





It would mean fitting a freewheel chainwheel if you mounted the Grubee on the r/h side like that. Just idle thoughts about how you could keep the brake on the back, it's always nice to have two of them.
 
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cannonball2

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Oct 28, 2010
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Colonial Coast USA.
You always find such great old things to look at. Makes me want to come over there and load a shipping container with all the cool stuff we never got.

I could jackshaft the build and make a shifter I guess but simplicity was the motive.

I bought this bike to have the discs for the E build. Would have been better off with the single speed version with a coaster in the rear for adding the Grubee. I could have added a disc to the front on the single speed pretty easily.
 

Ludwig II

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Jul 17, 2012
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The main reason that you can't use a sprocket as a disc is the contamination problem. I am surprised that with your history you haven't made a nice clean belt drive conversion.
 

MEASURE TWICE

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Jul 13, 2010
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A synchronous type belt (toothed-not cogged type), but not the regular V-belt I would liked to have chosen for my bike. The costs had me using 4L belt which is marginal on slippage.
 

MEASURE TWICE

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Those 2 stroke engines are easier to run backwards. Maybe a mirror image one of those contraptions on the right side to have a twin.
 

Ludwig II

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There's a concept. Retime the sparks, hang the engine facing backwards behind the back sprocket. Like this better view of a VAP 4

 

Ludwig II

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Jul 17, 2012
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I'm just musing about a job I wouldn't have to do, but is it possible to mount the final drive sprocket inboard of the bicycle sprockets on the r/h side, and mount the engine in the manner of mirror image of an FM38 Victoria or Fuchs?



In this additional picture, we have the twin of the Fuchs, the shcuF.
 

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sbest

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Nov 3, 2015
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This screams jackshaft and shifter kit...

My electric Schwinn Izip has an offset motor on the rear wheel and is no problem.
You know you can cut the rear mount down and carve (machine!) out a least 10mm from the front mount to set the motor in between those tubes? The intake would still need work and your sprocket problem not solved unless you went shifter kit...

Steve
 
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MEASURE TWICE

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Electric motors can be built into the hub, lets see a gas engine. Then figure inflight fueling!
 

cannonball2

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Oct 28, 2010
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Colonial Coast USA.
Was just about to sign on and say a family issue has arisen that will take me away from home and require my full attention for the next 4/6 weeks.

I spent the weekend organizing and packing away the parts for the three builds I have underway. Hopefully will remember what the heck I was doing/thinking when I get back.

This build is basically where it was at the last posting. Still haven't fully settled on its final configuration.
 

Ludwig II

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Jul 17, 2012
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Whatever the family issue is, we all wish you a happy and/or kindly resolution to it. Take care, stay safe.
 

KCvale

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Feb 28, 2010
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Phoenix,AZ
This screams jackshaft and shifter kit...
Steve
I agree.
My local bike shop had one for sale and just for giggle and grins I bought to see how it be motorized.

I ruled out gas right away so looked for other options.

This is how I made my Mongoose go as a dual disc 7-speed shifter.
Electric.







48V 1860W SBP electric mid mount kit.
48V 980W LI triangle Battery pack.

No muss no fuss sheer on demand geard power with good enough brakes to stop it, and it really needed them, the thing was a beast.

Those big tires take a lot of force to get them spinning fast.
It takes an equal braking force to stop their momentum.

NO motorized bike is safe without dual brakes, period.

To think that Mongose would be OK with just one brake best re-think that even with a disc, I am telling you this first hand, with the speeds mine would do it took all of the 2 discs stopping power to do it to the point of my thinking even lager rotors than the stock 160's for more braking power.

Just a heads up in time to give you some reflection until you are too far into your build.http://motorbicycling.com//www.pinterest.com/pin/create/extension/
 

cannonball2

Well-Known Member
Oct 28, 2010
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Colonial Coast USA.
Nice bike as always KC.

I have not decided if I am going to continue with this build or not. Its doable, but am thinking I will direct the time, money, and the engine to my GT2 frame collecting dust.

Besides I have a 500w hub kit for this bike that probably woudnt be used if I make it a gasser.

Just one of those passing ideas.

I brought my old Briggs 3hp flattie and a Schwinn Delmar frame with me on the trip to my sons to fool with and kill time.

It is progressing into my favorite build at this point. Should turn out well.

Some one build a fattie like this and finish out the thread. Heres the inspiration.

https://www.youtube.com/watch?v=okr3m3LY9N4