BrommiePlus 3 speed derailleur upgrade

[ExBrit]

Has anyone installed a BrommiePlus 3 speed derailleur? How happy with it are you?
They offer 17 and 18 big sprocket options. I've heard 18 tooth sprockets don't always work with unmodified rear triangles. Any input would be appreciated.
Apologies if someone has posted this before.
Thanks

 

[steveindenmark]

I think James Houston is riding one in the Transcontinental Race at the moment.

 

[tinywheels]

this beastie is of interest to me
surely someone has done the swap
more information please

 

[twentysix by twentyfive]

I don't know the answer so if it was me I'd get in touch with Brompton Bikes and ask

 

[berlinonaut]

I don't know the answer so if it was me I'd get in touch with Brompton Bikes and ask

As we are talking about a 3rd party mod by a Taiwanese company I do have my doubts that Brompton Bikes could and would be able or wanting to help...

 

[rualexander]

Not the BrommiePlus version, but I've got the MiniMods 3 sprocket kit (12/14/17t) fitted to my BWR hub, with a simple friction shifter set up.
Works ok, although the shifting has to be fairly precise. An indexed shifter might work better.
The BWR hub already has the correct driver fitted so didn't need to change that.

https://www.sjscycles.co.uk/gear-spares/minimods-brompton-3-cog-upgrade-kit-12-15-17t/

 

[404 Not Found Anywhere]

Not the BrommiePlus version, but I've got the MiniMods 3 sprocket kit (12/14/17t) fitted to my BWR hub, with a simple friction shifter set up.
Works ok, although the shifting has to be fairly precise. An indexed shifter might work better.
The BWR hub already has the correct driver fitted so didn't need to change that.

https://www.sjscycles.co.uk/gear-spares/minimods-brompton-3-cog-upgrade-kit-12-15-17t/

How does the MiniMods kit work with the 6 speed BWR gearing? I like the even steps between successive gears but one higher and one lower would be nice… does this help or is the spacing all messed up?

 

[rualexander]

How does the MiniMods kit work with the 6 speed BWR gearing? I like the even steps between successive gears but one higher and one lower would be nice… does this help or is the spacing all messed up?

This is the gear inches chart I get from Sheldon Brown gear calculator wit 34t chainring. I have a triple chainset on my Bropmton so also have 26t and 48t chainrings.

 

[twentysix by twentyfive]

As we are talking about a 3rd party mod by a Taiwanese company I do have my doubts that Brompton Bikes could and would be able or wanting to help...

Apols. Thought it was Brompton.

 

[ExBrit]

Apols. Thought it was Brompton.

This is an upgrade Brompton really needs to offer.

 

[tinywheels]

This is an upgrade Brompton really needs to offer.

I have been advocating for this type of thing for years However elsewhere on here I am derided for suggesting brompton need to get with the beat with regards to decent upgrades.