[Closed] 650B - dead already

Didn't say they were common necessarily, but FS Isn't universal in the same was as disc brakes, as per the original example.

Hard tails I feel are undergoing a resurgence in the UK as people either move from a FS back to HT or more likely buy one as a second, third bike, or build a single speed. Probably the majority of people I ride with have a hard tail, even if they ride a full sus also. Though I know a few who only have hard tails and talk of full sus as some kind of dark evil.

Then there's the whole field of All Mountain hard tails. Seen a lot of those about, and several I ride with have such a bike. I have one that would be an AM hard tail if it wasn't for the old rubbish fork I have on it.

And on the subject of AM Hard Tails *and* 650b... I give you the Bird 😀

[url= http://www.birdmtb.co.uk ]birdmtb.co.uk[/url] (especially the Zero.AM)

Reviews coming out in magazines now and coming out pretty good.

There are loads of HTs about here in the UK Mike, and for our indigenous brands (think On One, Singular, Cotic, Genesis etc) it's their bread and butter. (OK, Orange is an exception!)

futon river crossing - Member

The OP knows at least 2 650b riders on a Thursday night at Stanmer anyway - so his powers of observation pretty hopeless anyway ;)) !!!

Think that says a lot about the enormous difference between 26 and 650b doesn't it? I think the enormous logos they plastered 650b parts with are pretty telling.

iamroughrider - Member

was browsing at giant bikes and picked up a giant catalogue in a newish bikeshop, which list the pros and cons. Something like 6 small/medium disadvantages iirc over 26 inch.. then one largeish advantage considerably more contact area in theory...iirc mmmmm At least their honest I guess

(I am not a scientist but) I've heard it said that contact patch is dependent on weight/pressure and tyre carcass rather than tyre size- the shape changes but the size remains constant if all other variables are the same/equivalent.)

(I am not a scientist but) I've heard it said that contact patch is dependent on weight/pressure and tyre carcass rather than tyre size- the shape changes but the size remains constant if all other variables are the same/equivalent

For a a perfect circle touching a perfect plane, the contact patch will the same regardless of circle diameter. Other variables may make a difference but it's not directly down to the wheel size.

yeah i thought it was interesting at the time.

Think it was the contact patch though. Have a look yourself if you can. I think there was two or three pages with this information in the catologue.
It may well have been the contact patch whilst rolling obstacles .I think there was information about the angle of attack or something if i remember.

i guess for a given tyre pressure a larger diameter tyre will flatten more than a smaller tyre and therefore provide more grip. This was considerably more than a 26 inch and very close to a 29 inch without many of the 29 inch trade off's. The angle of attack was described as also much better than a 26 inch and not far off of the 29 inch. All the stat's on these and other factors are listed iirc.

For a a perfect circle touching a perfect plane, the contact patch will the same regardless of circle diameter. Other variables may make a difference but it's not directly down to the wheel size.

 

a tyre flattens though when load is placed upon it, so a larger tyre has a larger contact area. simples.

iamroughrider - Member

a tyre flattens though when load is placed upon it, so a larger tyre has a larger contact area.

Nah, because the larger tyre will deform less for the same weight. I think 😉

that's another feline friend just gone 😈

There is a reason why pressure is measured in pounds per square inch. Weight on the wheel divided by tyre pressure gives you the area of the contact patch in square inches. Tyre diameter doesn't enter into it. Ok, there are subtle differences in the shape of the contact patch and the way the pressure changes as the tyre deforms (which is linked to air volume) but these are second order effects.

I've got a 28er and a 26 and I can't say I've ever managed to detect this supposed difference in traction. There may be a small difference but it is irrelevant in practice. If you want more grip just fit stickier tyres.

i guess they roll better.

It is all fanny,

I was reading an old article about choosing wheels (not wheel size as this was before the new standard and surrounding guff but a buyers guide to what to look for when buying new wheels).

And it said the lighter the better,for all the obvious reasons, one being easier steering due to reduced gyroscopic effect blah blah.

And have read newer articles about the 650b saying it is better due to heavier/larger wheels mean more stability in a straight line due to gyroscopic effect blah.

Then lighter was better more acceleration, now a larger/ heavier wheel carries more momentum.

People have previously said that short chainstays are better easier to get the front wheel off the ground, more agile blah blah.
Now 650 are better as bike is longer, stability blah blah.

If you want a larger contact patch buy bigger tyres, or let your tyres down. greater contact patch means more grip,
horah, means more friction, boo.

Correct tyres. And you're golden, I have never suffered with a lack of grip an thought balls if only my wheels were a little bit bigger. No I though maybe a more appropriate tyre selection was needed.

The whole wheel debate and surrounding arguments are like Nostradamus,
Interpret as best serves your view point.
If you have a new bike, and it's great, I am happy for you.
But it's just a wheel that's a little bit bigger.