New bike build, hub gears & brakes, belt drive

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Brucey
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Re: New bike build, hub gears & brakes, belt drive

Post by Brucey »

I think you are on the right track there, and I shall watch developments with interest!

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~
bobc
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Joined: 5 Apr 2012, 11:59am

Re: New bike build, hub gears & brakes, belt drive

Post by bobc »

Shifter design, made from bits of scrap ally. This is designed to go next to the stem clamp on the drop bars where the diameter is 1.25". Novelty aspect of this one is that the twisty bit runs on a needle roller bearing to make it feel nice....
Image
design goals were to "not bind", not be too huge & clunky, and yet still be usable with cold, gloved hands....
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squeaker
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Location: Sussex

Re: New bike build, hub gears & brakes, belt drive

Post by squeaker »

bobc wrote:...the twisty bit runs on a needle roller bearing to make it feel nice...
Ah, you've used the standard Rohloff shifter then :lol:
"42"
bobc
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Joined: 5 Apr 2012, 11:59am

Re: New bike build, hub gears & brakes, belt drive

Post by bobc »

No, never used any rohloff stuff, I was just going off reports about other "aftermarket" shifters which garnered complaints about graunchy feel & being hard to hold (e.g. giles bertauld & another....) - they also didn't have the bigger (1.25") diameter to go round the bends on the drop bars & clamp to the stem clamp area. And the "an-other" looked clunky to my eyes......
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squeaker
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Re: New bike build, hub gears & brakes, belt drive

Post by squeaker »

bobc wrote:No, never used any rohloff stuff...
As a happy SRAM and Shimano gripshift user over many years on 'bents (but disliked them on upwrongs due to the sloppy feel when one pulls on the bars) I've found the shift feel of the standard Rohloff to be mediocre at best (mostly due to the inherent slack in a twin cable system) in comparison with a spring tensioned single shift cable. Probably worth putting up with for the system's many other virtues, though.
I can also appreciate the pleasure you will get from something effective "made from bits of scrap ally" in comparison to the expensive 3rd party efforts (but then I suppose the 'bobc twister' wouldn't exactly be cheap once all the overheads, your labour, the marketing budget and profit is factored in :lol: ).
Cheers.
"42"
bobc
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Re: New bike build, hub gears & brakes, belt drive

Post by bobc »

mmmmmm - new speedhub here in a (slightly battered) box c/w shifter cables nuts & oil.
It is rather nice.............
The buildup is going to take months......
cycle tramp
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Re: New bike build, hub gears & brakes, belt drive

Post by cycle tramp »

bobc wrote:Shifter design, made from bits of scrap ally. This is designed to go next to the stem clamp on the drop bars where the diameter is 1.25". Novelty aspect of this one is that the twisty bit runs on a needle roller bearing to make it feel nice....
Image
design goals were to "not bind", not be too huge & clunky, and yet still be usable with cold, gloved hands....


Definately a thing of beauty~ will you be taking orders to build any more? (surprisingly, or not, you can use a rohloff shifter with a nu-vinci n360 hub)
Motorhead: god was never on your sidehttps://www.google.com/search?ie=UTF-8&client=m ... +your+side
bobc
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Re: New bike build, hub gears & brakes, belt drive

Post by bobc »

"a thing of beauty~ will you be taking orders"
hell no!!! But you're welcome to a set of drawings :)
The "bits of scrap ally" plan isn't working either, I thought I had a 42mm diameter chunk for the main handle - turns out I don't.....
nil desperandum something will turn up, it always does :)
As it happens a standard shifter appeared in the box (contrary to expectations) so I can mount that on the side of the stem if my home-made effort turns out badly, or more hopefully, ebay it if it doesn't!
The hub is seriously bling - started buying rims & brake levers tonight....
bobc
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Re: New bike build, hub gears & brakes, belt drive

Post by bobc »

Just waiting for spokes now to build up new wheels.
The rohloff hub is pictured below, I laser cut a brake disc for it and belt sprocket laminations. The belt sprocket is for 14mm pitch HTD belt 10mm wide and has 18teeth. it is clamped around a standard rohloff 13T sprocket (the hub came with a 16T but that went very quickly on ebay) I have still to modify the "axle plate" then it's ready to roll.
Image
PS - in the background there is my home- made rohloff sprocket removal tool, took about an hour to rustle up & worked perfectly on the unused sprocket - I'd want to harden it before trying to undo one that had been used though :)
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squeaker
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Re: New bike build, hub gears & brakes, belt drive

Post by squeaker »

Nice: no wonder 'your' Greenpower team does well ;)

At Goodwood next weekend?
"42"
bobc
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Re: New bike build, hub gears & brakes, belt drive

Post by bobc »

Goodwood - yeah, fingers crossed for a podium finish....
For those who don't know http://www.greenpower.co.uk/
it's to teach kids that engineering can actually be pretty good fun :)
Should be an interesting day trip for anyone local - free entry but you pay to park a car. Dunno about bikes... I guess you can lock one to a tree or railing somewhere - as a motorsports venue I don't think it's well supplied with bike racks!
bobc
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Re: New bike build, hub gears & brakes, belt drive

Post by bobc »

shifter part 1 done... The roller bearing in the background
Image
co- motion does something like but theirs is major clunky & costs $250 !!!
Brucey
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Re: New bike build, hub gears & brakes, belt drive

Post by Brucey »

if the rollers in the bearing are in contact with the aluminium parts directly, might I suggest a little Keronite?

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~
bobc
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Re: New bike build, hub gears & brakes, belt drive

Post by bobc »

Thanks Bruce, yeah the rollers will be running on the handlebar material.
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