Frame Geometries - what makes a bike a bike?

[KneesUp]

I have a stripped down frame that I reckon is getting on for 20 years old here, that's got me thinking about what makes a frame of a particular description?

The frame I have stripped is all steel and has a downtube that is thicker than the one on my steel, fully rigid moutain bike from 1989, which means it has a strong (albeit heavy) frame, which will make an ideal commuter, It came with 700x38c wheels and tyres, but it will take a 2 inch tyre.

But given that the frame looks as tough as that of my mountain bike, and that it will take 2 inch tyres - what makes it a hybrid and not a 29er?

 

[raleighnut]

29ers didn't exist when your frame was built but it sounds like you could build it into one if you wanted, but its probable that the clearance was for mudguards.

 

[ufkacbln]

29ers didn't exist when your frame was built but it sounds like you could build it into one if you wanted, but its probable that the clearance was for mudguards.

Actually a 29er is exactly what the OP has!

It is all down to fashion and marketing!

Fit the 700c wheel size that has been used for touring, hybrids aetc for years on a mountain bike and tehre would be a massive outcry about how 700c wheels were unsuitable.

However call the 700C wheel a "29er" and market as the best innovation to hit mountain biking in years ..... people will not realise it is in fact a 700C wheel, and the buyers will lap it up.

 

[raleighnut]

Actually a 29er is exactly what the OP has!

It is all down to fashion and marketing!

Fit the 700c wheel size that has been used for touring, hybrids aetc for years on a mountain bike and tehre would be a massive outcry about how 700c wheels were unsuitable.

However call the 700C wheel a "29er" and market as the best innovation to hit mountain biking in years ..... people will not realise it is in fact a 700C wheel, and the buyers will lap it up.

That's exactly what I meant as 29er tyres weren't made then the closest you could get was a CC tyre'

 

[User6179]

I can remember 29ers in the 80s , they looked very strange compared with what was around at the time .

 

[ufkacbln]

I remember the advent of the RTB, the Road Touring Bike.

Basically take a mountain bike, fit it with road components and tyres

IIRC Richard Griggs from Avon Valley Cyclery used to sell these under the "Caribou" trade name

Edited - I was correct

From 2009:

I'm selling my faithfull RTB -one of the Caribou range I designed back in the 90s. This is a 'Vamoose' which means that it's very fast when needs be and can weigh as little as 22lbs. This is a genuine all-rounder as proved by lots of owners. It can be time trialled, triathlon'd, road raced, toured commuted or just ridden as a bullet-proof road bike.
The spec is mid-range - Campag Veloce/Chorus (I think) with 18 speed coming from a double chainset up front. The gearing is good for general use i.e. will get up most really steep hills and can still be pedalled at 40 mph.
There's rack mounts and mudguards are fitted. It uses V-brakes with Travel Agents which are 100% reliable and bomb-proof. This is done to get away from the dangerous practice of trying to squeeze mudguards under race-clearance brakes. The mudguard clearance is about 3/4inch. Tyres fitted are 1.3in but 1.75s can be fitted with necessary wider mudguards. Knobblied NOT recommended - buy a crosser if you're that way inclined...
Ride-wise - this is a very solid bike. Handling has been designed to mimick the classic road bike despite having lower inertia 26in wheels. For those who are interested this is done by having less fork offset to increase the stabilising trail.
The frame is made from Deda tubing, filet brazed by Lee Cooper. Paint job is standard Vamoose - midnight blue with gold forks. Top tube falls away towards the rear in classic KONA style. Rear triangle is long to give heel clearance to panniers.
Size-wise this bike would suit any one between 5' 10" and 6' 3" who likes a long reach - the virtual top tube is 58cms.

.. and I found some pics!

 

[KneesUp]

The Caribou is all kinds of lovely, and is the sort of thing I want to build out of the frame I have.I'd have to go some to get it down to 22lb though!

 

[TheDoctor]

So the latest thing of a 29" MTB is just a hybrid with slightly wider tyres then?
And the even-newer-than-that 650B is hardly different to 26 by 1 3/8"?
I was riding those off-road when I was 12!