Frame mounted CY460R SHIFTER!!!

D

dchevygod

Member
OK guys I've got big plans to take a new Motobecane 500ht along with a 46cc 2stroke goped engine, mount it to a 4 stroke engine plate and attach to a sbp freewheel crank via a 5:1 gear reduction for a quality 2-stroke shifter. Anyone seen anything like that before?

I think this could be epic because that motor/5:1 trans/20:1 final drive on an axle mount I built would touch 50mph with a completely stock motor ;) http://www.davesmotors.com/chung-yang-146224460-gp460-engine-4-2hp-cy.html

I built the axle mount when I lived in AZ, I now live in CO Springs and the terrain is really bad here. So a shifter to utilize the power from a stop or up a big hill is needed. The roads here gave My axle mount mount a terrible demise :(

I'm making a big purchase of parts when my taxes come back.
1) Motobecane 500ht
2) CY460R/mount
3) SBP freewheel crankset/sprockets
4) 1gal fuel tank/line
5) a couple 5:1 redux transmissions " one to use and a spare to upgrade the bearings on "

That will get me rolling after figuring out the chain line and modifying the mount plate for my 460, I think lol. But I am looking to find a 3 or 5 SPD Sturmey Archer IGH at a decent price with a usable shifter as soon as possible. Any thoughts or comments are appreciated.

Any one have a good 1 gallon peanut tank for sale let me know.

All I'm really worried about is space and flow for the brake levers f-r for disc/shifter & twist throttle. Everything else is pretty straightforward.
 
I think I may have thought out a way to keep my handle bars almost unchanged. My plan is to take both shifter/brake controls apart and see if I can swap parts over from the 8speed into the 3speed shifter body, for a 8spd shifter on the left, then modify the right side 8speed shifter/brake lever to be a thumb throttle! I think that it'll work but I need to open them up to make sure. If I can get it working like I want I won't need all new controls. And the bars will be very clean :) just an added mirror for safety.
 
I saw a 460 driving a 5 speed cassette. small diameter tire and a single 5/1 tranny, he used a derailer. no peddels on that thing. hit high 40s i think
 
is this similar to what you have in mind?

This one works well with a stock 49cc making 2hp. Tops at 35 and cruises nicely at 30. With nearly 5hp I would think 50 just might happen.

Amazingly the Nexus IGH is holding up well with kind treatment. Have a build under way on a similar bike using a Briggs 3hp that should put the Nexus to the ultimate test!

http://motorbicycling.com/showpost.php?p=627136&postcount=14
 
cannonball2 said:
is this similar to what you have in mind?

This one works well with a stock 49cc making 2hp. Tops at 35 and cruises nicely at 30. With nearly 5hp I would think 50 just might happen.

Amazingly the Nexus IGH is holding up well with kind treatment. Have a build under way on a similar bike using a Briggs 3hp that should put the Nexus to the ultimate test!

http://motorbicycling.com/showpost.php?p=627136&postcount=14
Click to expand...


I had seen that one before, nice bike. Yours is a jackshafted motorcycle ;) and mine will be a pedal assist shifter. But yes very similar in theory, but what's your opinion on my ratio at the moment. My trans is a 5:1, the primary reduction after that is 4.9:1 for 24.54:1 then a 23 primary to the 8 SPD cassette first is 32t for .72:1 and a first gear final drive of 34.24:1 right?
 
Don't know why last post didn't go thru.

Thanks for the welcome mat man.

Bjm also thanks for commenting, I've done small tire stuff all my life on gopeds and also converted a Schwinn CD-500 to a gasser, while yes the gearing is easier to get right on a small tire, the ride quality suffers.

I've got my head set on the sturmey 5spd . the %25 gear spread thru 5 gears will be awesome on a correct ratio sprocket. I'm capable of figuring out the sprocket sizes needed, but I need a starting point.

So I'll throw what I ordered together and let the testing begin. The cassette gear isnt as low as it could be though, its the 32t they make a 36t shimano for 8spd. That may be how I do it on the cassette. Take apart 2 cassettes and Use the larger gears. So its a custom low ratio 34t 1st, 32t 2nd, 30t 3rd, 28t 4th, 24t 5th, 21t 6th, 18t 7th, 16T 8th. I haven't worked thru all the #s but it seems good to me. I'll need a 34t and 30t cassette to dismantle, and cobble them together with the 32t that's on the bike. All just for a temporary solution ;)
 
cannonball2 said:
is this similar to what you have in mind?

This one works well with a stock 49cc making 2hp. Tops at 35 and cruises nicely at 30. With nearly 5hp I would think 50 just might happen.

Amazingly the Nexus IGH is holding up well with kind treatment. Have a build under way on a similar bike using a Briggs 3hp that should put the Nexus to the ultimate test!

http://motorbicycling.com/showpost.php?p=627136&postcount=14
Click to expand...

I'm sure I'll hit 50 on the flat ;) that looks really nice actually! I just have to have pedals. So a bit different route was needed for me. I'm not the innovator of these things and am glad for it, there are so many different kinds, variations of the same style MB the inspiration is everywhere. I've just got the bug that's all!
 
dchevygod said:
I had seen that one before, nice bike. Yours is a jackshafted motorcycle ;) and mine will be a pedal assist shifter. But yes very similar in theory, but what's your opinion on my ratio at the moment. My trans is a 5:1, the primary reduction after that is 4.9:1 for 24.54:1 then a 23 primary to the 8 SPD cassette first is 32t for .72:1 and a first gear final drive of 34.24:1 right?
Click to expand...

My ratios work out to 29:1 in 1st...22:1 in 2nd and 16:1 in 3rd. The Nexus has the direct drive in second gear. Under driving 1st at .733 and over driving 3rd at 1.364.
My engine is pretty torquey and pulls the 1st ratio from a dead stop well not having pedals. My state quit requiring pedals on MBs and I guess I got tired or lazy and stopped building certain builds around them.

Entering the specs of the motor you are using with my ratios yields a top speed of 56mph@11k rpms I think my 16:1 final might be a bit tall for your higher reving engine.

I built a similar bike using a CAG motor and a derailleur shifter and its low gear was around 31:1 as I remember. It pulled nicely from stop and the gaps in the ratios were perfect. It hit the sweet spot on the power band with each shift. The cogs were the standard starting with a 28t and dropping in 4t drops to a 14t The CAG was much faster overall than this 49cc, but this engine is light years ahead in usability.

I would calculate for the top gear at the max speed you want(that is reasonable for the engine to pull) and the lower gearing should fall in to place. You may be a bit low overall, but that just might work out better for the 46cc engine as it will probably unload at the top near your 50mph mark. If not juggle the ratios a bit.
 
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56mph at 11k! This motor winds out at over 13k stock! Yeah. I may be over geared, I'll see when I get it together.

Thanks for chiming in CB.
 
The mount plate arrived. But its narrower than the engine bosses :( I'll have to get a little more inginuitive with the mount design.
 
dchevygod said:
I'm sure I'll hit 50 on the flat ;) that looks really nice actually! I just have to have pedals. So a bit different route was needed for me. I'm not the innovator of these things and am glad for it, there are so many different kinds, variations of the same style MB the inspiration is everywhere. I've just got the bug that's all!
Click to expand...
Hi Chevy, we have talked in e-mail.

Predicting top speed with gear ratio math after ~30mph is a joke.
That is when wind resistance starts becoming a real drag, literally.

You need more power to overcome it, or get aerodynamic to lesson the drag to even get close to the math speeds.




http://motorbicycling.com//www.pinterest.com/pin/create/extension/
 
This power plant has gone 50+ for me on an axle mount 26" wheel at 20:1. As long as I can get the parasitic chain drag to a minimum and the ratio where i want. I have over come the wind drag before. But thank you for your insight. If I get the thing together and it won't do what I think now I won't be too disappointed.
me draggin a modified goped with my axle mount 460 link below
https://youtu.be/BmCA7LUVMuk

Oh and I only weigh 170lbs. That bike was geared really high as well but I pedal hard to get going anyway. It balanced out. It took a while to get there but it would do 50. 40 all day no problem.
 
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Lol yes KC we definitely are.

Well after some headaches acquiring appropriate hardware. I think I have sorted out the freewheel assembly. The 24t is spaced over an inch away from the 54t with some long m5 bolts and #10 spacers. It looks good.

But now that I'm this far I can see that the plate itself needs to come up a few mm's " handy adjustable mount " or just use some washers to take up the chain slack. The angle on the seat stay tube side of the HD mount needs a little work but the main downtube matches well. This is all coming together.

img_20160229_174940654-jpg.71234


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This one is with the sbp hardware installed and its not gonna jive.
img_20160301_203947268-jpg.71246


I decided to use the left side 3spd shifter as a thumb throttle and leave the right as a is, since no one makes an 8spd triggershift for the left :,(

I hope the mounting of the motor goes well in the morning. I don't have the straight edge I'd like too, and my eye is only soo accurate lol.

I need to make the chain and mount the fuel tank, then I can run the new cable housing over the repurposed 3spd shifter/throttle cable and adjust it.

After that its fuel time, and I'll need some old school bean oil for the break-in period .shft.
 
dchevygod said:
Lol yes KC we definitely are.

Well after some headaches acquiring appropriate hardware. I think I have sorted out the freewheel assembly. The 24t is spaced over an inch away from the 54t with some long m5 bolts and #10 spacers. It looks good.
Click to expand...
The 4-stroke SBP shift has an extra part to attach the freewheel to the crank shaft so it is not attached to the pedal crank arm so you can move it on shaft and align it with the back wheel.


img_20160301_203947268-jpg.71246


vs.

2_BigRedTensioner700.jpg


I decided to use the left side 3spd shifter as a thumb throttle and leave the right as a is, since no one makes an 8spd triggershift for the left :,(
Click to expand...

Oh man, really REALLY bad idea bud.
Never EVER use a fixed click setting for the throttle, you need absolute full range throttle control that returns to idle when released.

There are thumb actuated throttles for ATV's, try one of them if you insist on a left side throttle.
Personally, when it comes to handlebar controls I am down right anal about them being right, especially on a shifter.

2 pull levers, 2 twist levers is it.
One of each on both sides.
That's all your 2 hands can deal with and still pay attention to the road.

For a 2-stroke with a clutch lever and dual hand brakes you use a dual pull brake lever on the right.

A 4-stroke is easier, no clutch lever, so just use a rotary twist shifter on the left and still have dual independent brake levers and a proper full function throttle on the right.

RedGT2done2bars.jpg


Just get yourself an 8-speed rotary shifter and put it on the left.
The readout is upside down but that don't matter.
In short, ditch both the thumb shifters, they have no place on a motorized bike anyway, ever.

Just a fair warning tip not a slam, take it or leave it bud, but I hope you follow my advice if you want to enjoy your ride ;-}




http://motorbicycling.com//www.pinterest.com/pin/create/extension/
 
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Thanks for your advise KC. I totally agree that it can't ratchet or lock. So I removed the latch and trigger completely, its now just a left side thumb throttle. I really can't believe how well it works and was so frickin easy! I also maintain the exact same look of the handlebars so I got that goin for me and that's nice.
 
This is better

img_20160303_133759085-jpg.71261


img_20160303_133708604-jpg.71260


Now it functions thru all the gears but first, and I'll make a chain stay to keep the chain from falling off so 1st works.
 
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Cool!
What you want for the seat post bar above the pedal sprockets is called a 'Jump Stop', it keeps the chain from jumping off the front sprocket when you are in 1st.
 
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