potsy
Rambler
- Location
- My Armchair
mmmmm, there's always one
you still up for waddington?
Sorry, couldn't resist
I'm up for Waddy, not sure about my aching legs
Brompton Gearing
- Thread starter Brommie77
- Start date
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Sorry, couldn't resist
I'm up for Waddy, not sure about my aching legs
mickle
innit
- Location
- 53.933606, -1.076131
Trolling?
mickle
innit
- Location
- 53.933606, -1.076131
not that simple on a brompton, the rear triangle only takes up to 16 toothed sprocket unless you start grinding the rear triangle away (& voiding your 5 year frame warranty).
The front ring is a maximum of 54 (iirc), or it interferes with the fold.
so unfortunately your not a brompton rider & have given duff advice
I've owned several Bromptons over the years - we have one in the garage right now. But wait, there's more: My first industry job was as a Saturday assistant in the Victoria Bicycle company - C1983 when it was the one and only shop which sold Bromptons and before they had alloy rims. Since then I've served 23 years in cycle retail, twenty of which were in Brompton dealerships. I once held the unofficial speed record for folding a Brompton. I've written articles on them. I've given talks and I've demonstrated them to audiences of up to fifty people on cycling holidays. Worked on them, adapted them and hot-rodded them. Until recently I was responsible for the servicing and upkeep of a fleet of 400 bikes which included twenty assorted Bromptons. I've done the Brompton factory tour and shaken the hand of Andrew Ritchey. I even know Steve Parry.
(iirc)
GrumpyGregry
Here for rides.
^ now that is a great comeback.
So...... would adding the three speed gear give me faster movement for the same pedal speed, or would I just have the same limits with more choice in between?
Rohloff_Brompton_Rider
Formerly just_fixed
not really, all that pontification and he still didn't answer the question.
also i forgot earlier, the rear derailleur will only take up to a 18 toothed sprocket.
the lowest being 14 i believe, due to the chain snagging the rear triangle.
so personally, in your situation, i would go for the schlumpf speed drive or high speed drive. just a bit more cash for a perfect solution. the bwr is an option but i'd prefer not having an extra cable to play with. i have a schlumpf and it is so reliable and simple and no cables to foul and lose gears.
GrumpyGregry
Here for rides.
As well as the various gear ratios, would the cadence be limited by the wheel size? I have a M3 which I use in town for work purposes from time to time, and even in top gear I find that I am pushing and spinning the top gear, yet not going nearly as fast as a large wheeled bike. Surely a 16 inch wheel, no matter what gearing will never be that fast?
GrumpyGregry
Here for rides.
Pull a big enough/right gear and in theory no reason why 16" wheels can't make a bike go as fast as a 700c wheeled one surely?
Is such a gear available for, and within the constraints of, a Brompton? ( I have visions of a huge chainwheel gouging the tarmac). That I don't know
Rohloff_Brompton_Rider
Formerly just_fixed
there are theories that smaller wheels are faster, eg, less aero drag, less rotational mass etc etc. not sure on that theory myself. but, didn't some world speed record get set by a 16 inch wheeled moulton? and didn't moultons do really well in racing until they got banned?
RecordAceFromNew
Swinging Member
- Location
- West London
According to their spec the 2 speed's highest gear ratio (which I figure is 12T x 54T on something like a 16 x1 3/8 tyre) is 74 gear inches, which is roughly equivalent to a 15T x 42T on 700c. Requiring 100 rpm at the pedal to hit 22mph, I can appreciate that it can be a little too busy for some.
However if the OP hasn't already he might want to check if he has 12T (and 16T) x 54T at the moment - it seems some come with a 13T at the back and 44T or 50T up front.
However if the OP hasn't already he might want to check if he has 12T (and 16T) x 54T at the moment - it seems some come with a 13T at the back and 44T or 50T up front.
Cheers for the comments people, I will have to make a tooth count later - it was a standard spec when I bought it, but goodness knows what that actually was. I am contemplating upgrading as I want more speed 
but just trying to make sure I don't spend loads to get no improvement.
Paulus - pedal faster! I frequently leave other bikes behind (although not the really serious ones) its great fun to see their reaction when they realise I'm on 'one of those folding shopper bikes'
Will have to do some more persuading of Mrs B that the money is well spent upgrading!
but just trying to make sure I don't spend loads to get no improvement. Paulus - pedal faster! I frequently leave other bikes behind (although not the really serious ones) its great fun to see their reaction when they realise I'm on 'one of those folding shopper bikes'
Will have to do some more persuading of Mrs B that the money is well spent upgrading!
suecsi
Active Member
- Location
- Feltham, Middlesex
Glad I'm not the only one that gets that - apparently I am going at a fair clip according to my hubby as he sees me ride down the road from home to the station, but I am just at a pace that is comfy for me, I'm not actually trying to go particularly fast. I had to do my first overtake last week which was interesting.
I have found that my balance on the Brommie is a little better when at a higher speed, although my slow balance is getting better through experience (I have to go pretty slow, or sometimes get off and walk the bike, at night as the shared ped/cycle path is chaos when the shops are open).
I have found that my balance on the Brommie is a little better when at a higher speed, although my slow balance is getting better through experience (I have to go pretty slow, or sometimes get off and walk the bike, at night as the shared ped/cycle path is chaos when the shops are open).
Hi Brommie 77.
I was in exactly the same position a while ago having bought the same 2 speed version as you. I bought it as I only intended to use it around W1 instead of taxis at work.
Of course, I got hooked and it's sheer versatility meant I was using it for up to 20mile+ commutes etc and twiddling away in top(2nd) gear started getting very frustrating very quickly....in fact I never even used 1st!
I did a load of calculations ....even considered getting a custom larger front ring but in the end settled for upgrading to a 6 speed as I was using it regularly for my 26mile per day commute and could justify the expense.
The 3 speed hub alone would have given a little more speed for the cadence, but I really wanted something that would keep up with , ahem, 'proper' bikes so went for broke and got the 6 speed. This meant a new hub and changer, but because I already had the rear deraillieur, I didn't have to fork out for it.
It weighs a bit more(I feel that I do notice the difference) but this is more than compensated for by the extra vroom.
I put the slimmer, lighter slick tyres on it and it really flies.....tho I was puncturing at least once/twice a week
BTW I put mini bar ends that really make a difference when on the rivet. £20 well invested.
Not sure if I've answered your question but good luck with your choice.
Cheers.
I was in exactly the same position a while ago having bought the same 2 speed version as you. I bought it as I only intended to use it around W1 instead of taxis at work.
Of course, I got hooked and it's sheer versatility meant I was using it for up to 20mile+ commutes etc and twiddling away in top(2nd) gear started getting very frustrating very quickly....in fact I never even used 1st!
I did a load of calculations ....even considered getting a custom larger front ring but in the end settled for upgrading to a 6 speed as I was using it regularly for my 26mile per day commute and could justify the expense.
The 3 speed hub alone would have given a little more speed for the cadence, but I really wanted something that would keep up with , ahem, 'proper' bikes so went for broke and got the 6 speed. This meant a new hub and changer, but because I already had the rear deraillieur, I didn't have to fork out for it.
It weighs a bit more(I feel that I do notice the difference) but this is more than compensated for by the extra vroom.
I put the slimmer, lighter slick tyres on it and it really flies.....tho I was puncturing at least once/twice a week
BTW I put mini bar ends that really make a difference when on the rivet. £20 well invested.
Not sure if I've answered your question but good luck with your choice.
Cheers.
Thanks wobbles, sorry for the delay, I've been away for a day or two.
You have given me the answer that I wanted - so cheers. Bromptons are very nippy, but as you say, sometimes you just want that bit more. I was concerned that the 3 speed would not be enough, so its nice to know that you have had success with the 6 speed.
I've also added some bar ends (a while ago now, and really notice the difference, my other bike is a tourer, and I was missing the drops, but the ends give a change of grip now and again)
Now I definately need to butter Mrs B up!!
You have given me the answer that I wanted - so cheers. Bromptons are very nippy, but as you say, sometimes you just want that bit more. I was concerned that the 3 speed would not be enough, so its nice to know that you have had success with the 6 speed.
I've also added some bar ends (a while ago now, and really notice the difference, my other bike is a tourer, and I was missing the drops, but the ends give a change of grip now and again)
Now I definately need to butter Mrs B up!!