Originally Posted by
AL NZ
At 240 lbs, I gave my 1960s 3 speed Sturmey-geared BSA a proper mountain biking for 3 hours the other weekend. Downhill, rocks, tree roots, the works. It had 26 x 1 3/8 tyres, only slightly fatter than the old "10 speed" tyres at 27 x 1 1/4.
And it is still in one piece
So I would say, Yes, Do it.
The SA axle is not robust enough to handle repeated abuse like that... Raleigh did make a BMX version with a stronger axle but these are rare.
I took my '73 Gran Sport for a little ride last spring that saw everything from gravel to pavement to snow...
