Brompton owners

Just got another email from ridelondon telling me I have a place in the Brompton World Championship again. I don't know what to believe anymore...

Haha, there's an idea! Situation at the moment is that I got an email saying I had a place, then got an email two days later saying the first email was a mistake and that I don't have a place. Now I've had a 3rd email telling me I do have a place again...

Just followed the link to try to pay for my place, and it's saying it can't find my details on the system.

I'm assuming I don't actually have a place after all...

So it begins. Colour flip titanium Brompton.

I know Brompton suggest replacing the sprockets when fitting a new chain, but after just 1100 miles over 6 months? Seriously? Went back to the 50T chainring yesterday, and rather than refit the links that I took off when downsizing to the 44T I decided to buy a new chain. The 16T was "Ok", but the 13T jumped like buggery under any strain.

Must be made of cheese.

Really need to investigate more into converting SRAM sprockets.

Still haven't put my 58t on, but hadn't even considered having to replace the sprockets (think I've done about 1k miles so far). Will bear that in mind... Will also look into sram sprockets...

Just paid for my BWC entry. I think/hope that means I'm officially in. Any other forumengers got a place?

I put mine in for a service at Brompton Junction yesterday and apparently they are replacing sprockets, chain, brake pads, seat sleeve etc. - I've done around 1k miles if that helps.

I've been having a look around, is there any reason these two sprockets wouldn't work?

https://www.sjscycles.co.uk/sprockets/sturmey-archer-14t-sprocket-332-flat-9-spline-hsl912/

and

https://www.sjscycles.co.uk/sprockets/sturmey-archer-12t-sprocket-332-flat-hsl893/

I think I want the gears closer together and both a bit higher, more of a headwind/tailwind setup, rather than too easy for a headwind/too easy for a tailwind, that I've got at the mo'.

So with the 58t and a new chain, would the above do the trick?

Chain and sprocket wear out faster on a Brompton, especially considering how close the chain and cassette is to the Tarmac and the small sprocket also a major contributing factor.
what you described is sound very normal.

If you want it to last longer, a 3 speed or single speed will do this.

Are you not running a 12t sprocket already?

I'm on standard 2-speed gearing, so 12 and 16 I think?

But I've done around 1000 dirty winter miles so far and am looking to replace the chainring (for a 58t) and therefore new longer chain as well. From what @Evell and the poster on the last page said, it sounds likely that the sprockets will require replacing as well, so I may as well go for new everything and change the ratios a bit, right?

So do you think those sprockets will work?

Looking at it, the 14t is flat, there's no guide for the chain to jump on/off like your 16t sprocket;

With this in mind, I cannot comment on whether it will work or not.

If you're fitting a bigger chainring, so maybe stick with it? (with new sprocket obviously).

Ah fair enough, hadn't considered that...

I think I'll buy a replacement set of standard sprockets plus try to source a 14t that'd fit and see how I get on with the standard ones.

I just rarely find myself using the easy gear and would prefer a bit more of a slog setting off if I had two usable gears the rest of the time.

Do you know if there are any other 14t options out there with the ramps to shift?

Making progress. After much hassle with HRMC I received my Gumwalls.

You're getting a chainring with an extra 4t, that would be enough noticeable change as it is.

If you ridden a single speed before, then you'd remember how much of a difference a 1t sprocket make (with chainring, 2-3t difference give similar result).

Yeah I think I worked out previously that I'd end up with 60" and 80" with the 58t.

Commuted around London on 84" fixed for a few years with no problems, so I think that'd be ok, but I think I'd prefer there to be a bit less of a jump between the gears.

I'll give it a try with the standard ones anyway. Do I need the whole sprocket 'kit' with the black plate thing and spacers (I think, can't tell from the pics online), or do I just need to buy the sprockets themselves and can re-use the rest?

You can do either. I'd replace the spring clip after a couple of goes though as it starts to look a bit second hand with corrosion.

The 13t from a 6 speed can be used instead of the 12t on a 2 speed if that helps. That lowers standard gearing to 69 inches.
For other sizes you'd need to dismantle a 9 spline Shimano cassette.

anyone got any silver risers 25.4mm with 2-5cm of rise, looking to swap the bars out on my brompton, not worried about length, as I'll cut them down anyway..
thanks

All good info @edscoble, @spj7 and @BQ, cheers!

Think I'll buy the full replacement set and fit them along with the 58t, see how I get on.

Oh and I've bought 2 folding kojaks for £30ish off ebay for the BWC. Marginal gains etc. :)

I'll give it a try with the standard ones anyway. Do I need the whole sprocket 'kit'.

Short answer, no.

Oddly isn't more expensive than 2x cog.

You may have commuted on 84" fixed Ok, but bear in mind that the Brompton will almost certainly be heavier and less aerodynamic than whatever bike you were using.

Yep, you're right regarding both weight and aeros, but I'm spending a lot of time spinning wildly on 74" at the moment and barely ever using the 54" gear. Def need them bigger.

New sprockets ordered, anyway. Will stick the 58t on at the weekend if I find a minute...

After wanting one for years I've finally ordered a Brompton rear rack!

My life is so rock'n roll!