What surprises me is that - on the face of it - the geometry isn't so very far from my '92 Stumpjumper in many ways. The frame angles, wheelbase, and chainstay length are almost identical. The bottom bracket is higher, but the big difference is in the handlebar position. The Cleland's fork is longer, and the head tube is nearly twice as long. It's the handlebar position that's chiefly responsible for the weight shift up and back, not the frame angles.
It's important to remember that this bike has 650B wheels and 2inch tyres giving an overall wheel diameter of about 27.5 inches. For this wheel size, the wheelbase is short.
You are correct in saying that the high handlebars are the key factor in moving the weight backwards. They are also the key factor in allowing BMX style, rapid shifts in body weight. Another key difference is the large wheel/frame clearances and lack of rim-brakes, which allow the bike to cope in the worst of muddy conditions.
For those not used to riding a Cleland, the high bottom-bracket and resulting inability to touch the ground whilst in the saddle, can be scary. However, the extra height is one of the delights of Cleland riding. You soon learn new ways to adapt and to dismount safely in an emergency. Cleland riders tend to be good at track stands, moving slowly over obstacles, and prefer to jump off, than fall off.
Hi Old Ned.
The tubes came from David Wrath-Sharman's furtive imagination & garden shed. The choice of tubes is down to an analysis of the forces each should withstand. The forks, for instance, are intended to bend without damaging the frame. The Allen key removable freewheel is from the same source and is very straightforward. The treaded portion of the hub can simply be detached from the rest of the hub by undoing three Allen key bolts located on the inside of the hub flange. This is best done with a ratcheted Allen key.
The bottom bracket axle is also Allen key removable and adjustable and the cranks have self-extracting Allen key bolts. I believe that this was the last Cleland that David Wrath-Sharman ever made and its design is the culmination of 20 years of evolution from both Geoff Apps and David Wrath-Sharman. Of course, both were helped by all those who tested earlier bikes and components, to destruction in many cases.
The list of Geoff and David's innovations found on this bike is long. Many have since been taken up by the mainstream. Others have not. Some still remain unique and novel, 20 years after the bike was made.