With modern tyres better, like Bigger Apple: 305 on Brompton acceptable/useful?

[SA_SA_SA_SA]

Now that modern fat tyres,  like Bigger Apples, have much better rolling resistance than in the past.... do  305 rims have a place on some  Bromptons?
( standard  Brompton rims are the larger 349mm size)

For more suspension or also (like in a past AtoB magazine experiment) knobblys for 'off-road'  muddy rough tracks etc.

Presumably brakes would need to become V-brakes or hub brakes* (a pity as avoids quick wheel comparisons / swaps ).... Nevertheless, some people have fitted V brakes neatly.



*cos very long reach  calipers would be rubbish.

[Arellcat]

305s on a Brompton has been done at least a couple of times.  Ben Kinetics did it with disc brakes.

http://www.kinetics-online.co.uk/folding-bikes/brompton/herberts-big-apple-brompton/

While Bromming around London I never felt the need for anything fatter than ye olde Kojak, but in more northerly places, with our frost shattered, lunar landscapes of so-called tarmac, Big Apples onna Brompton is not a bad idea at all.

[rogerzilla]

Marathon Pluses only just fit on a Brompton - there's not much width between the seatstays.  How wide are Big Apples?

[SA_SA_SA_SA]

Thanks, very interesting, Arellcat.

I think I would choose  the Greenspeed hub for front and either a V on the rear or want Ben at Kinetics to modify his rear frame to protect the rear disc when folded.

But all hypothetical for me.

Rogerzilla:  I think that Kinetics has a custom rear frame.
EDIT but it seems almost unnecessary for 305 wheels according to
http://www.atob.org.uk/folding-bikes/off-road-brompton/
(some rear tube crushing required )

[SA_SA_SA_SA]

Also, a 2in 305 rear tyre would allow a more robust(?) Marathon Plus(5mm thick puncture defence) or Marathon Green (3m puncture defence) whilst leaving a reasonable amount of air in the tyre for suspension (unlike modern skinny 349 pluses/greens)....

Front tyre could of course remain a nice faster 2in 305 diameter  big apple.....

[SA_SA_SA_SA]

Given that modern UK rail companies don't seem very fussed about folder size anymore (ie anything with 20in wheels goes) even though the Brompton is one of the few that would satisfy the stricter National rules of carriage :

I wonder if (an official) modifying of the Brompton frame so that it could accommodate  fat 47-349 (or even 55-349) big apple style tyres would be worth it: would simplify production while keeping the benefit of the larger 16in wheel size.
A front hub brake or V brake would be required though....

[Kim]

Given that modern UK rail companies don't seem very fussed about folder size anymore (ie anything with 20in wheels goes) even though the Brompton is one of the few that would satisfy the stricter National rules of carriage

I'm not sure that's true.  Some of them (eg. London Overground) talk about "compact folding bikes", which is a de-facto euphemism for 'Bromptons'.

[SA_SA_SA_SA]

... Some of them (eg. London Overground) talk about "compact folding bikes", which is a de-facto euphemism for 'Bromptons'....

Wouldn't they need to specify the folded size (like National rail doc) to avoid unnecessary arguments? Specifying a 20in wheel or less is at least a little bit more definite.

[Kim]

... Some of them (eg. London Overground) talk about "compact folding bikes", which is a de-facto euphemism for 'Bromptons'....

Wouldn't they need to specify the folded size (like National rail doc) to avoid arguments?

I think they're more interesting in avoiding bicycles than avoiding arguments.

[SA_SA_SA_SA]

Nevertheless, I wonder what effect on folded Brompton size the ability to take fat 349 tyres would have: if it still fitted the national rail guidelines then it might be worth it..

[Kim]

Nevertheless, I wonder what effect on folded Brompton size the ability to take fat 349 tyres would have: if it still fitted the national rail guidelines then it might be worth it..

Absolutely.  And there must be plenty of Brompton owners who never go near a train, but would value a fatter tyre.