Push Bike question - from Dérailleur changer

BillN

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Has anyone seen one of those front Dérailleur rod changers - the manual one where you put your hand down and twisted a rod to change front chainrings

I had one on my Uppadine Bike years ago, (early 1960's) - made by campag - but they were quite common at the time

could one be easily made plus a clip on 43mm in diameter? - it's quite a simple thing - just for two front Chainrings

I'm trying to figure out how to put two chainrings on a Brompton - the two chainring part is easy - it's the changer that will be difficult - the tubes on the Brompton are 45mm, or is it 43mm in diameter and there is no room

Bromee_1ab.jpg
 
Why two chainrings?
It feels like you are overcomplicating the whole thing. What you really need is an Alfine (like Rohloff but way cheaper) 8 or 11 speed hub gear. Simple, wide gear range. Effective
 
Why two chainrings?
It feels like you are overcomplicating the whole thing. What you really need is an Alfine (like Rohloff but way cheaper) 8 or 11 speed hub gear. Simple, wide gear range. Effective

Not really as I am after the "lightest" 6 speed set up

The rear end of the Brompton with not take a normal Dérailleur - you have to modify the Brompton "Chain pusher" which is only built for a two sprocket rear set up

There is only room for 3 "10 Speed" type sprockets on the rear, (just about take up the same space as two SA sprockets) - I just need a Shimano 10 speed Cassette and then use the 13t 15t and 17t - 17 is the biggest that the back will take without affecting the fold

I have the Alfine spyder/cranks/BB - and the (Outer) Chainring is Middleburn

I have spend hours looking thru the web for options

(the Brompton alternative is a 3 speed rear SA type Hub and two SA sprockets, plus their "chain pusher = about £350)

Thanks - was aware of Rohloff, as you say very expensive ..............was not aware of the Shimano 8 speed Hub - presumably it can be built into a 16" wheel - is it the same width as a SA Hub
 
Why two chainrings?
It feels like you are overcomplicating the whole thing. What you really need is an Alfine (like Rohloff but way cheaper) 8 or 11 speed hub gear. Simple, wide gear range. Effective

Just checked it out Davey

for the Afine hub you need a rear frame spacing width of 135mm ....... the Brompton is 115mm so a new "rear triangle" is needed - Kinetics do them at £400 or £725 for a new triangle, Alfine Hub and changer.

The easiest way to get 6 speeds is the Brompton SA way = about £350 - Rear Hub and two sprockets

my way, if it works should be cheaper and lighter
 
Just checked it out Davey

for the Afine hub you need a rear frame spacing width of 135mm ....... the Brompton is 115mm so a new "rear triangle" is needed - Kinetics do them at £400 or £725 for a new triangle, Alfine Hub and changer.

The easiest way to get 6 speeds is the Brompton SA way = about £350 - Rear Hub and two sprockets

my way, if it works should be cheaper and lighter

Blimey, know nothing about Bromptons and at prices like that (and no need for a small wheeled folder) I'll stick with 'bigger' bikes. Good luck
 
Just waiting for my second Brompton to arrive - being shipped from the UK to France - TNT - £70 - hope it doesn't explode

Black Edition M6L
 
Just waiting for my second Brompton to arrive - being shipped from the UK to France - TNT - £70 - hope it doesn't explode

Black Edition M6L

I DO NOT want a second Brompton...My Brirish racing green M6L is a beaut'

BUT...That orange S3L..(only done ten miles)...for sale elsewhere on here is so so tempting......Wish I had gone with the S bars in the first place...:blast

Enjoy the M6L BillN.....:thumb2
 
I DO NOT want a second Brompton...My Brirish racing green M6L is a beaut'

BUT...That orange S3L..(only done ten miles)...for sale elsewhere on here is so so tempting......Wish I had gone with the S bars in the first place...:blast

Enjoy the M6L BillN.....:thumb2

The Orange S3L is a good buy, (I would have had a go had it been nearer and I think Gerry wants it collected rather than shipping it) ....... go for it and try the nano electric assist kit for £800 - runs on Bosch 36v power tool batteries, (£100) - probably 10 miles per battery - but they are not heavy so you can carry 2 - I may have a go with a kit in a couple of months time
 
I remember the rod operated front mechs, and my dodgy memory tells me the rod was quite long as needed for a rider to reach it from the seat. Your pic of the Brompton suggests there’s not a lot of room for a rod long enough for a rider to reach it without interfering with the folding mechanism.
 
I remember the rod operated front mechs, and my dodgy memory tells me the rod was quite long as needed for a rider to reach it from the seat. Your pic of the Brompton suggests there’s not a lot of room for a rod long enough for a rider to reach it without interfering with the folding mechanism.

There are "conversions" around that use a conventional cable front Dérailleur - I have a list of the bits and pieces needed and some people, not many, just use their right foot

In the end I gave up and just bought a regular 6 speed Brompton
 
There's a three speed hub so when you take into account the six speed X 3 speed hub gives 18 speed, Nexis do one that's the cheapest start from £400 then upto £1200
 


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