DIY Shift Kit Project--'The Shifty Beast'
- Thread starter lowracer
- Start date
No matter how you do it, mounting an engine with a shift kit on this bike will be one heck of challenge.
For a soft tail shifter it really helps to start with a bike with the rear suspension behind the seat post like this one.
I look forward to seeing how you do it as I have had move than one person ask about motorizing that style of soft tail.
For a soft tail shifter it really helps to start with a bike with the rear suspension behind the seat post like this one.
I look forward to seeing how you do it as I have had move than one person ask about motorizing that style of soft tail.
KCvale,
The transmission will be mounted directly within the frame tubes, but the engine will hang out to the left a bit (like the scooterguy kit no longer available). Fortunately the bottom bracket I bought from SickBikeParts is extended on the left side to allow room for my left foot to pedal a circle should I need to.
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The transmission will be mounted directly within the frame tubes, but the engine will hang out to the left a bit (like the scooterguy kit no longer available). Fortunately the bottom bracket I bought from SickBikeParts is extended on the left side to allow room for my left foot to pedal a circle should I need to.
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I got one of my Mitsubishi engines mounted up today to test for clearances. Its definitely not for pedalling much but possible in a weird kinda way.
I haven't hooked up chain yet and may explore mounting the engine out back behind me and running the chain to the front chainring?
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I haven't hooked up chain yet and may explore mounting the engine out back behind me and running the chain to the front chainring?
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Attachments
Maybe one of your cags would be better? You could probably hang it from the bottom tube between the front wheel? Or at the front of the top tube just behind the handlebars?
Wont fit down there (crankarm strike), That's as far forward it can go without the transmission making contact with the frame tubes. I was going to throw a chain on it & test it out before trying a rear mounted engine setup...but I like to incorporate a rear derailleur (upside down) for engine chain management.
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Would be much harder to do that on a suspension bike though! Nowhere to bolt anything! That looks like a good serup tho how did it work out?
I'd have to mount it solid to the frame up higher than the seat, unless I use a rear derailleur chain tensioner which would eat up the chain slack as the suspension moves up and down (probably use this method).
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I got the project completed today & got to take it for a test drive.
It was cool being able to start out in 1st gear with no pedalling and then shift down through some gears. I am a bit cramped with the seat and engine so very close but it is kinda cool.
Here are the pics.
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It was cool being able to start out in 1st gear with no pedalling and then shift down through some gears. I am a bit cramped with the seat and engine so very close but it is kinda cool.
Here are the pics.
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Uber cool and looks great, LR. (Would a lay back seat post help?)
I just caught your gear shifting concept. (wut? I are slow, ride the short bus and sleep wearing a helmet)
ARHHGGG, very, very cool!
I just caught your gear shifting concept. (wut? I are slow, ride the short bus and sleep wearing a helmet)
ARHHGGG, very, very cool!
Dan,
Yeah I think a lay back seatpost is just what this bike needs to fit better.
Thanks for the great input!
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Yeah I think a lay back seatpost is just what this bike needs to fit better.
Thanks for the great input!
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I took it for a 2nd longer test drive to get it up to speed & through most of the gears (the highest few (smallest on the rear cassette) are way too tall for a small engine to pull).
Glad to see that my method of aligning the engine sprocket & big chainring worked like a charm. Its not the most advanced, high tech method, but it works. I simply use two vice-grips & a piece of metal bar. Clamp one end of the bar to a flat spot on the big chainring and the other end to the sprocket on the transmission. Then take a good visual from both sides to see if it looks parallel. The rear derailleur on the non-drive side section of chain allows for both taking up the slack and fine tune chain alignment.
I didn't have any issues with the chain flying off at high rpm's or when going over bumps.
For my next project, I'm seriously considering building a front wheel pedal drive MBB recumbent (moving bottom bracket). Then motorizing the rear wheel with 8-9 gears to shift thru under engine power & being able to pedal, powering the front wheel.
I've already got the 'Hugh Jass' super-cushy saddle for the seat bottom & another long saddle for the seat back-rest.
Now gotta find a good donor bike being thrown away to pillage the rear triangle. I'll probably also brace it with a tube connected above the headset.
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Glad to see that my method of aligning the engine sprocket & big chainring worked like a charm. Its not the most advanced, high tech method, but it works. I simply use two vice-grips & a piece of metal bar. Clamp one end of the bar to a flat spot on the big chainring and the other end to the sprocket on the transmission. Then take a good visual from both sides to see if it looks parallel. The rear derailleur on the non-drive side section of chain allows for both taking up the slack and fine tune chain alignment.
I didn't have any issues with the chain flying off at high rpm's or when going over bumps.
For my next project, I'm seriously considering building a front wheel pedal drive MBB recumbent (moving bottom bracket). Then motorizing the rear wheel with 8-9 gears to shift thru under engine power & being able to pedal, powering the front wheel.
I've already got the 'Hugh Jass' super-cushy saddle for the seat bottom & another long saddle for the seat back-rest.
Now gotta find a good donor bike being thrown away to pillage the rear triangle. I'll probably also brace it with a tube connected above the headset.
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the beast looks good! but can you really pedal? that front wheel drive thing looks like great fun!
Pedalling 'The Shifty Beast' is a joke. My left leg needs to move at an obtuse angle. I guess with a shift-kit, you dont need to pedal much unless the engine quits. I think Dan's idea of a lay back seatpost would add the necessary space to pedal more naturally. I'm still not completely sold on having the engine directly in front of my leg and may find a better placement for the engine. Maybe I'll turn this full suspension beast into the recumbent??? Hmmmm
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Looks like you have the perfect set up to mount the Sachs KM48 rotary motor I've been seeing lately, elsewhere on the 'net. He reckons it hangs out the right hand side only 5 and a half inches or so. Would have to use a jackshaft of course as it mounts on the right and this comment doesn't help if you haven't got/ can't get a Sachs KM48 rotary motor lol. 
Anyway, cool bike! Love what you're doing. It's giving me ideas and daydreams.. as you can tell
Anyway, cool bike! Love what you're doing. It's giving me ideas and daydreams.. as you can tell yeah a layback would at least help if not cure the problem. what kind of speed did you get out of it BTW? "the shifty recumbant" now that i'd like to see!