Shifting???

Bikewithamotor

Bikewithamotor

New Member
Hi, I have a stock 44t rear sprocket which maxes out on the road pretty quick. So...I mounted a 24t right next to it. The engine doesnt have enough power to start going in this gear, so I was wodering...

Does anyone know of a good way of shifting gears? (Please not the 250 dollar shift kit!)

Homemade designs are sweet if you have one!!!

Thanks
 
The standard kit is only $180, but I hear what you are saying. My initial attempt at a shift kit was to use a derailleur on the left side to try to make a three speed. Didn't work out very well because when you try and bump start the engine the derailleur would unwind, loosen your chain and it would fall off. I am sure others will have some ideas for you though.
 
Bikewithamotor said:
Hi, I have a stock 44t rear sprocket which maxes out on the road pretty quick. So...I mounted a 24t right next to it. The engine doesnt have enough power to start going in this gear, so I was wodering...

Does anyone know of a good way of shifting gears? (Please not the 250 dollar shift kit!)

Homemade designs are sweet if you have one!!!

Thanks
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I would like to see your set-up with the 24T mounted right next to the 44T. Do you have pics?

Jim
 
Search google for "Jackshaft / Shiftkit / Freewheel"

I have a thread out there that might give you some ideas.

It's not completed totally.

Someday i'll finish it.

I don't know about cheaper though.
 
A Sbp Shift Kit Or A Cvt Belt Box Is The Best Thing You Can Do For Any Motor. I Weight 0ver 300 And My Titan 49cc With Shifter (sbp Shifter Pieces) Amaze`s Me Every Time I Ride. Motor Developes Awsum Torque With Out A Lot Of Rpm`s. If You Could Test Ride A Shifter Bike, That Would Be It!! A Shifter Build Is Better Than Any Mods. Ron
 
Pablo said:
You could wait for our dead of winter sale!
Click to expand...

orly? o.O

oops Pablo - you may have just postponed a purchase lol :D


Bikewithamotor - not to dissuade any DIYers, but after a buncha research I've found the SBP's shift kit isn't as expensive as it seems - when you add up all the costs of the various parts (the freewheel sprocket on the crank being one of the biggest) and all the effort in R&D... it's actually quite reasonable and you know it'll perform.
 
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I'd save my pennies and go with SBP's shift kit. Just put one on a bike for a customer and it's sweet as can be. With his 3 speed nexus hub he can start in first gear without pedaling and in third, with a good flat road and a back wind he can hit close to 50 mph.

Be safe when you ride at those speeds. All we're going to need is a few dumbasses killing themselves (or someone else) then bingo, new laws will no doubt be passed.
 
Bikeguy Joe said:
I don't think the stock engine will pull a 24T on a 26" bike anyway.
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Absolutley true. Even a 28t is close to worthless, even on a slant with expansion pipe. If 24t did work the difference between 24 and 44 is too much for any deraileur anyway.
 
I'm not sure how the math works. It seems that any two sprockets next to each other on a hub, must be sized so that they match the pitch of the chain for proper shifting.

I have no idea how great the difference in tooth count in two ajoining sprockets, could be.
If I were able to figure all that out I would fab a two or three max cluster.
 
When I Looked Carefully At The 7 Speed Cassette Off A Regular Pedal Shifter Bike, There Is Much More To It Than I First Thought. There Are Ramps To Move The Chain Up And Other Mods. It Is Not A Simple System. Ron
 
Yeah...i'm kinda tight on cash right now so I'm wondering if for now I should just have the 24t sprocket mounted...use the 44t normally, and when I come to a flat stretch just hop off and manually shift the chain over. (I could have a little pouch behind the seat of tools I would need to take the slack out of the chain) Its a pretty foolproof idea and what I'm doing is just taking that extra power from my engine and putting it to use. I recomend that you do this yourself because as you can see in the attachment, there is plenty of room for a smaller sprocket on the average bike. :)

What do you think?
 

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It took a fair amount of R and D but I'm pleased with how my transmission turned out. I'm going to take the motor off and put a 4 stroke on it just as soon as spooky tooth gets them in stock. I'm having reservations about the grubee 4g box but I know Roland is a stand up guy and will replace it if its crap. He said his kit is going to cost 250-300 dollars. As far as shifting is concerned, I'll never go back to single speed. can't wait to see SBP 4 cycle shift kit. peace.
 

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Lets build it right here in the kitchen! LOL! I ordered my jackshaft a couple of days ago. I'm like a kid at christmas. Just two more days. I'll keep ya'll posted.
 
MaxPower said:
It took a fair amount of R and D but I'm pleased with how my transmission turned out. I'm going to take the motor off and put a 4 stroke on it just as soon as spooky tooth gets them in stock. I'm having reservations about the grubee 4g box but I know Roland is a stand up guy and will replace it if its crap. He said his kit is going to cost 250-300 dollars. As far as shifting is concerned, I'll never go back to single speed. can't wait to see SBP 4 cycle shift kit. peace.
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First Tandem I've seen with a motor on it MaxPower. I bought an old rusty tandem last summer with plans to put 2 motors on it. You've re-inspired me to do a little more planning on it...Thanks

Dug out my photoshop prototype. .weld.

tandem2.jpg
 
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