Motobecane scooter spring and variator brake assembly

Made a compact version of my variator brake. Utilizes the scooter contra moby mod as well.

Have to remove the original spring mount, but the advantage is amazing.

Steel shaft coupler clamp with brazed bronze bushing. Pulled by cable to left hand lever.

Might work better with a different material for the bushing, maybe lined with cork or friction material.

But works good so far, just need a longer lever.

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Re: Motobecane scooter spring and variator brake assembly

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Re: Motobecane scooter spring and variator brake assembly

Wow this is pretty awesome.

Re: Motobecane scooter spring and variator brake assembly

Decided to forgo the leather friction bushing because I'd like to see how the bronze bushing wears in to the steel shaft.

Might spread some lapping compound on the shaft and then try to get them to seat to each other perfectly over time. If they grind against each other enough the assembly should become grippy af over time once the fit is perfect

Re: Motobecane scooter spring and variator brake assembly

yeah the chrome shaft is probably more of the problem than the bronze. either way this is a rad idea, you could make one out of just about any shitty old stock moped shock

Re: Motobecane scooter spring and variator brake assembly

Well, went on a long ride and it needs work. Not easy enough to lock the shift with the left hand even with a longer lever. It's the kinda thing you have to have an easy grip or it gets annoying fast.

That's why I prefer a hydraulic caliper so far.. 2 bikes have mechanical calipers, one has hydraulic and the hydro is sooo easy. I love it.

Think I'm going to try a few things.

First I'm going to add sipes or notches to the shaft like a brake rotor. Those do help the grabbing action.

I'll glued a leather strip on both sides after redrilling the bushing to 3/8 to accommodate the leather thickness.

Now to let it dry and see if it's better

Re: Motobecane scooter spring and variator brake assembly

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Re: Motobecane scooter spring and variator brake assembly

Maybe if the clamp arms were longer ...

But , I see there isn't much room for that .

Re: Motobecane scooter spring and variator brake assembly

It works much better now,

Can do what it's supposed to do without too much hand effort.....,but...

I'm competing against a diff braking system with very different square inchs of clamping force.

With a bike caliper, you have maybe 2 square inches of clamping area.

On this I have 1 inch max, maybe less.

So yeah, gotta do special things to improve the leverage. Already using a fat 2mm+ cable, so.....to do:

1. Extend the clamping cable side of clamp for more leverage.

2. Make a custom lever, very overbuilt with a long arm.

I guess I could get a hydraulic piston and run it to a hydro brake calipers but that seems kinda insane. I do have an old hydro motocross rear foot brake. Ohhhh no that would be super fucking nuts

Re: Motobecane scooter spring and variator brake assembly

Why not just make a second one and bolt the arms together laterally while pulling from the middle of the two? Seems like that would be the easiest and most "made of junk lying around" way to increase the grabby coefficient

Re: Motobecane scooter spring and variator brake assembly

I might go up in shaft size.

Larger shaft, more square inches of brake clamping area.

Re: Motobecane scooter spring and variator brake assembly

Think I found the answer.

Hydraulic clutch cable.

Joe xmb63 posted on my other duel variation thread with this pic,

I bet I can make it work.

It would be so much stronger and easier to use than using a manual lever omg

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(edited)

Re: Motobecane scooter spring and variator brake assembly

Megasaurass wRexckses /

That looks like it’ll work with an exhaust header too.

The ad pic is stupid tho, that cheesedick needs to wipe the Jiz off his lens and set the part up so it’s not all mangled into itself. Ya know. Cool part!(edited)

Re: Motobecane scooter spring and variator brake assembly

Megasaurass wRexckses /

It’s a moped power valve actuator fuxtik!

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Gougle pics of Yamaha jet ski. Order 2 or 3 more of them levers for later. :)

Re: Motobecane scooter spring and variator brake assembly

I realized that I should go with an aluminum shaft due to it being much more grabby than steel. All the other vari brakes I've made I use aluminum as the clamped piece.

Now to find some aluminum tube to attach over this steel shaft.

Re: Motobecane scooter spring and variator brake assembly

What about brass tube? Brass on brass?

Or grove the bolt for more grip?(edited)

Re: Motobecane scooter spring and variator brake assembly

Aluminum grabs really well with friction material. I don't know why.

It's perfect for this due to its slow linear feed and need to lock it in.

I think leather and aluminum will be perfect

Re: Motobecane scooter spring and variator brake assembly

Yup. Way better.

Basically the same as my other cable brake setups now.

Aluminum and leather or any friction material for the variator brake just performs so well. Idk why.

Very grippy

Welded a drilled shaft collar to a nut, then screwed it onto a 8mm bolt welded to the shock eyelet I used previously. I happened to have a 5/16 (8mm) aluminum rod here in the junkpile.

I'll still mount the hydraulic lever and cable when it comes just to try them. Pretty cool lil thing. I'm learning things that are totally bitchin bro seriously bro

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Re: Motobecane scooter spring and variator brake assembly

Jonathan Feldman /

I know this isn't variator brake related.. But god I love that engine spring. I always felt like polini spring on peugeot had just a bit too many coils in it per inch and it wouldnt variate all the way through the range smoothly. Im not sure I typed that too well but I think you know what I mean. I feel like that engine spring must have very linear variation with how much space there is between the coils.

Hmmmm. Crazy shit.

Re: Motobecane scooter spring and variator brake assembly

Zuma and jog Scooter contra springs are great on French bikes.

But these days I do so much manual shifting with the brake the spring doesn't matter much, just a little

Re: Motobecane scooter spring and variator brake assembly

Dirty30 Dillon /

Yeah, someone should produce a swung engine spring setup that uses standard contra springs.

Re: Motobecane scooter spring and variator brake assembly

Thats the whole point of this.

I hope to produce this, but wanted a locking mechanism included because it's amazingly fun to run

Re: Motobecane scooter spring and variator brake assembly

I wonder if this design would work.

Would be getting away from the "brake" idea and more to a spung ball bearing shift point lock concept.

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Re: Motobecane scooter spring and variator brake assembly

For whatever reason my Peugeot hangs out in the low gear a little too long and shifts almost like a 2 speed. I think I would like to have more of those in my shift range. Holding a foot brake seems like it might be more enjoyable than shoving on a launch lever. I like how much tighter and clean this version looks than the previous iterations.

Re: Motobecane scooter spring and variator brake assembly

One needs to prove a concept first which I did. It's amazing.

Then designs can change to accomplish the same thing in varying ways.

Re: Motobecane scooter spring and variator brake assembly

Are you using a gas spring? I hear they do that.

Daniel '' Wrote:

> -------------------------------------------------------

> For whatever reason my Peugeot hangs out in the low gear a little too

> long and shifts almost like a 2 speed. I think I would like to have more

> of those in my shift range. Holding a foot brake seems like it might be

> more enjoyable than shoving on a launch lever. I like how much tighter

> and clean this version looks than the previous iterations.

Re: Motobecane scooter spring and variator brake assembly

Megasaurass wRexckses /

Sounds neat, I found a piece with a similar ideaR

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Re: Motobecane scooter spring and variator brake assembly

Josiah Radebaugh /

My Pug does that aswell with a new variator. I just figured it was light variator weights. Maybe not.

Re: Motobecane scooter spring and variator brake assembly

Made a square notch shifter today on the bike. It's awesome. Very different but equally as fun. Less arm work for sure

Chunk of HDPE, drilled hole in center, cut a slot across the back to hold the gear retainer notch arm, then gave it a pivot and cable to pull it up and a strong spring to hold it in.

And....cut the notches in the center shaft.

And and and and and and it's really kinda nifty

Last pic is the notched shaft under the bike thru the frame, notches filled with grease

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Re: Motobecane scooter spring and variator brake assembly

Nice work . ;)

This stuff really makes me miss my shop .

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