As a general rule of thumb when buying/building a bike I size them partly by making sure that when I’m in a normal riding position the front hub is hidden by the handlebars. This comes from road riding days and has served me well (at least as a starting point) for many years. But recently I’ve ridden a few MTBs where I can clearly see the front hub (and half way up the forks in some cases) in front of the bars. I’d take that to mean that they are too small, but they actually felt fine to ride. So, just wondering if anybody else uses the hub behind the handlebars “rule” for mountain bikes.

I’m thinking that, since it was based in road bikes, it probably assumes a 72 degree head angle, so isn’t going to apply to something with a slacker HA.

Cheers,

Andy

WTF are you on about?

is this some dusty old roadys method for sizing a bike?

Its a roadie meausring method.Though Ive found it a resonable ballpark to work from.

I used to be able to see my hub behind the bars. Then it was obscured. Now I can see it in front of the bars. I don’t think it has any meaning off road.

it’s a good starting point to fine tune from

To answer the question though, I dunno, I’ll go look

I use it on my Retro rides, but not on my newer ones. My C456 I can see all of the fork lowers on aswell as the hub.

No – my tyre is too wide

I can’t see mine, it’s way too dirty

(and my belly gets in the way.. 😳 )

It is an interesting thought imo.

I’ve always used it and found it to be about right for road bikes, but never really thought about it for mtbs.

However, on recent mtb rides I’ve felt a little too stretched and nervous down rocky hills (CYB for instance) and noticed that the bars are a fair way past the front hub when looking down.

Quite the opposite of most new slack angle short stem frames, but I might just drop the 110mm stem down to 90mm and see how it feels.

I can see mine. It’s on that spare set of wheels over there ->

cookeaa – Member

WTF are you on about?

is this some dusty old roadys method for sizing a bike?

Nice reply…

The tyre obscures it…

It’s still a good reference point for top tube/ stem length on a road bike, but totally irrelevant on today’s slack angle freeride contraptions. 🙂

A ‘chance’ thing from road bikes – a guide at best. if of any use at all on MTBs, it’s a sign that it’s too steep, long in the stem, or somehow wrong imo. I reckon on most of my MTBs I can see much of the fork, the hub is well ahead of the bar and should be…

It is something I have heard about but never practised. Interestingly whilst trying out a few bikes recently, I’ve noticed I can see the hub behind the bar. Is that a good thing?

I can’t see my hub as my belly obscures it, haven’t seen my cock either for 7 years….

How slack are some of your bikes and how short are the stems?!

I can see my hub and most of my forks BEHIND the bars!

loddrik – Member
haven’t seen my cock either for 7 years….

We had it for xmas dinner in 2005 😳

Errm, it depends where I put my head.

I’ve always used it and found it works well

I can see my hub through my rim if that counts for anything. 😉

2010_1129cheesewheel0024 by singlespeedstu, on Flickr

Thanks all.

So a fair bit of humour, but nothing close to a consensus. We’ve got everything from well behind to well in front and “yes it’s a good rule of thumb” to “totally useless off road”. I think I tend to agree with the latter. It probably works fine on a 72/72 road bike, so can’t really work on, say, a 73/66 mountain bike. Not sure I can see how a proper fit would have the hub behind the bars when riding along the flat, but it takes all sorts.

Cheers

Andy

My god that Rim! ^^ *speachless*

road bikes are generally similar in geometery.

comparing a rigid xc bike to a DH rig is nonsense.

Hub = knob
Handlebars = gut

A. no

My god that Rim! ^^ *speachless*

Why’s that then.

Safer to look where you are going than down at the front hub 😉

Janesy – Member
My god that Rim! ^^ *speachless*

Its a wheel, wide for wide tyres, drilled for lightness…

where you been the last few years? 😆

That rim reminds me of the old Mongoose Pro Class bmx wheels.

I once had a pair of them, on a Supergoose 🙂

I was waiting for Janesy to tell me how it would explode if i rode down a curb on it. 🙄

I was told that by other “experts” on here. Well it’s had a right good thrashing and it’s still going strong almost two years later. 8)