brompton v tourer.....

[Rohloff_Brompton_Rider]

has anybody got a brompton and a touring bike with the same kit?

what i'm trying to find out is whether it's worth ditching the brompton for a tourer. my brompton has a very wide gear ratio (21" to 109") thanks to the schlumpf speed drive and 6 speed bwr system, it also has a shimano dynohub lighting system, the position on the p bars is quite comfy but upright.

on the brompton yahoo group someone made the very good point that i can't compare my commute times with my drop barred cx bike, due to aerodynamics (my commute is overall downhill one way and overall uphill coming home).

what i was trying to find out, is why the brompton feels like i'm riding thru treacle compared to my fixie and cx bike.

i'd put it down to the 2 internal geared hubs, but on paper and according to manufacturers info, i should only be losing 4% to 6% overall which is bugger all and worth the compromise on a folder, however, i can lose 20 minutes average one way (on a 20 mile one way commute) to my cx bike, but i couldn't go touring on my cx bike, where as my brommie is brilliant at touring and long distance rides (except when i didn't use the front luggage system with tubby and broke some spokes on the back).

so,

has anybody got a tourer with the shimano dynohub lighting system with flat bars, if so, is your average speed a lot lower (more than 3 or 4 mph) than your drop handled lightweight bike?

 

[TheDoctor]

I've not got dynahubs on any of my bikes, but my Brommie is markedly slower than my flat barred tourer.
On my recent trip to Epernay, I averaged 10 mph on the Brommie, where I'd expect more like 13 mph on the tourer.
Partly, it's that I never feel like hurrying on a tour, and the Brompton exacerbates that to some degree. That, and the fact that I just can't climb as well on it.

 

[Rohloff_Brompton_Rider]

I've not got dynahubs on any of my bikes, but my Brommie is markedly slower than my flat barred tourer.
On my recent trip to Epernay, I averaged 10 mph on the Brommie, where I'd expect more like 13 mph on the tourer.
Partly, it's that I never feel like hurrying on a tour, and the Brompton exacerbates that to some degree. That, and the fact that I just can't climb as well on it.

i know it's weird isn't it? the saddle and bars positions are almost identical when side by side. the tyres are pumped upto max pressure and both are slicks.

i'm glad that someone else finds the brommie markedly slower, on the yahoo group they say that the brommie is pretty much the same as other bikes. i thought something was wrong.

 

[StuAff]

A folder compared to a fixed frame bike (regardless of wheel size) is bound to flex more, so you lose efficiency there. Throw in aerodynamics (both of the bike itself and your riding position), weight difference (if any), and you've got a load of small but important factors. On my Dahon Jetstream XP, I was 10-15% slower on similar rides compared to my road bikes- and I bet the extra two or three kilos (11 kg for the Jetstream) accounted for most of that. I've just got a newer Dahon, a Speed Pro TT, and it's noticeably quicker- same drivetrain (9 speed derailleur plus SRAM DualDrive, though I have a smaller range cassette on the TT), but better riding position (bullhorn bars adjusted so it's like riding a roadie on the hoods), a bit lighter (maybe a kilo), and a noticeably stiffer frame. Still not as quick as the roadies, but not by much- I reckon 5%.

 

[Little yellow Brompton]

has anybody got a brompton and a touring bike with the same kit?

what i'm trying to find out is whether it's worth ditching the brompton for a tourer. my brompton has a very wide gear ratio (21" to 109") thanks to the schlumpf speed drive and 6 speed bwr system, it also has a shimano dynohub lighting system, the position on the p bars is quite comfy but upright.

on the brompton yahoo group someone made the very good point that i can't compare my commute times with my drop barred cx bike, due to aerodynamics (my commute is overall downhill one way and overall uphill coming home).

what i was trying to find out, is why the brompton feels like i'm riding thru treacle compared to my fixie and cx bike.

i'd put it down to the 2 internal geared hubs, but on paper and according to manufacturers info, i should only be losing 4% to 6% overall which is bugger all and worth the compromise on a folder, however, i can lose 20 minutes average one way (on a 20 mile one way commute) to my cx bike, but i couldn't go touring on my cx bike, where as my brommie is brilliant at touring and long distance rides (except when i didn't use the front luggage system with tubby and broke some spokes on the back).

so,

has anybody got a tourer with the shimano dynohub lighting system with flat bars, if so, is your average speed a lot lower (more than 3 or 4 mph) than your drop handled lightweight bike?

I have a P6L and a Voyage tourer ( drop bars) both with dynohubs , the Voyage is MUCH quicker than the Brompton.

 

[Rohloff_Brompton_Rider]

I have a P6L and a Voyage tourer ( drop bars) both with dynohubs , the Voyage is MUCH quicker than the Brompton.

assuming you spend more time on top of the drops....exactly the info i'm after.......cheers.

 

[mickle]

I reckon the biggest factor is riding position aerodynamics, and then all the other little things add up to become significant - rolling resistance, dynamo drag, Schlumpf + internal hub drag. And those Brompton 2spd jockeys can get sticky too.

 

[Red Light]

There is some real life measurements of the efficiency, rather than manufacturer's claims, of different gearing systems here. I wouldn't be surprised it the combination of the losses of the rear hub and the speed drive makes up a large chunk of the difference.

 

[Rohloff_Brompton_Rider]

I reckon the biggest factor is riding position aerodynamics, and then all the other little things add up to become significant - rolling resistance, dynamo drag, Schlumpf + internal hub drag. And those Brompton 2spd jockeys can get sticky too.

my thoughts too, but on yahoo brommie group, the figures given (from manufacturers) are in imho a bit conservative. but i don't have a full wheeled flat bar tourer to compare.
the above post is near enough to confirm my experience.

cheers guys

shaun

 

[Arch]

I have no idea how my Brom compares speedwise with my other bikes, I just know it feels as fast, or faster, because it's nippy!

I'd think about more than speed though, in a decision whether to ditch the Brom for a tourer. After all, the reason you have a Brom is the fold. Your range is much increased, if you can bung the bike easily on a train or bus.

Now that I have one, I think if it came down to being forced to have one bike only, the Brom would be it for sheer convenience, and fun!

Also, if you lose 20 mins on a 20 mile ride, that's an extra hour to do a 60 mile day (my ideal daily touring distance would be 50-60 miles). That doesn't seem to bad, over a whole day, if you're out to enjoy yourself as opposed to munch miles.

 

[david1701]

talk to this guy a bit on twitter, he's a legend, tours on a folder with a baby trailer because he can carry everything on a variety of public transport options http://www.mikemcfarlane.co.uk/photography-tips-and-articles/view/the-cycling-photographer/

 

[Rohloff_Brompton_Rider]

talk to this guy a bit on twitter, he's a legend, tours on a folder with a baby trailer because he can carry everything on a variety of public transport options http://www.mikemcfarlane.co.uk/photography-tips-and-articles/view/the-cycling-photographer/

good site thanks, but kinda enforces my point. i think i'll use the brommie this week. the wind is nasty for fixie-ing uphill. i hope it'll be like getting back on an old friend.