Don't suppose anyone could give their views on this - have a 1968 B40 which I use for green laning and LDTs - I believe the frame is a WD (the engine is 1965). A friend came round the other day and reckons my frame is bent because the downtube bows in slightly towards the engine. I've looked at photos of other similar B40s and some of the frames seem to be bowed like mine (although some don't). Any views on whether my frame is actually bent? May be largely academic as even if it's a bit bent it rides ok and may not matter that much to me (although if it's bent that could give me the excuse to invest in the Faber Otter frame I've been hankering after!). If anyone's interested the forks are R.E.H. and have totally transformed the bike. Front hub is Gerry Minshall alloy, rear hub is original crinkle QD. Photo attached.. apologies for state of bike - am planning to clean it later - honest!
I have a similar B40 and the gap between the 21x275 tyre and the front engine mount is 167mm, in a straight line towards the front wheel spindle. It is not beyond the bounds of probability that any bike of that age has hit a wall at some time, and maybe pushed the forks backwards. If it has only changed the fork angle by one degree, I don't think that will affect the steering, it might actually increase its cornering response.
You could measure the wheel spindle wheelbase, but as the rear is adjustable, that might not give meaningful results.
Thanks scifi much appreciated - I'll measure the gap on mine later. As you say if it's taken a bit of a hit in the past and steepened the head angle slightly that will quicken the steering response and help me out in the trials sections!
Hi,
I suspect that this is either not a WD/B25 frame of has been modified. The rails from the shocks to the swing arm pivot and a cross piece above the SA indicate this. It could be that the curve in the front tube is deliberate to alter the geometry. Is the top tube bent? Looking a bit closer, the seat loop/subframe could be Tiger Cub.
Dave.
Thanks for your comments Dave and apologies for the delay - I've been away for a while. Top tube is fine & beginning to think curve in front tube is intentional as you say. Does appear frame may have been modified. Bike is something of a Bitsa & engine is from a 1965 b40 Star (engine no. beginning with F). Have new Faber frame on order anyway & will rebuild engine when it's out the frame. Can't resist fiddling about with this bike but it's all good fun. Thanks again for your feedback. Regards, Andy