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[jefrs]

Well that seems to have sorted it. Took it for a blast up Combe Gibbet trying to make it step-out (not recommended), wouldn't do it, it didn't want to do it, couldn't make it do it even on loose stuff. Hurrah! It would seem that correct torque on the swinging arm bolt is critical; it took so little to tighten it that it must be very fussy. However I had also torqued the large front engine mount and the large rear engine/subframe mount from which the swinging arm pivots; although not loose they did need to be a smidgen tighter. The frame feels a lot tauter and the handling tighter so it feels like the bike can be chucked about without it doing anything silly now. So lesson learnt, periodically check the torque on mounting bolts. Sorted. Thanks, Jeff.

[papasmurf]

Anyone who can get a spoked motorcycle wheel to flex just using muscle power either eats three Shredded wheat for breakfast or there is something badly wrong with the wheel.

[jefrs]

Dennis, and you've never found you can flex the wheel rim on the the hub? I'm surprised. There's a lot of stuff on wheel building out there in lala land but it never beats first-hand experience.

[PeteF]

Very strange Jefrs. I check spokes by tapping them. A ting means they are tight, a clunk means they need nipping up. Never noticed any difference top and bottom.

[jefrs]

Four shredded wheat Papasmurf I'm built something like a gorilla, more like an overweight one these days. I used to do a lot of thoroughly daft sports, which probably accounts for why all my joints are shot now.

[papasmurf]

PeteF, I agree, I really do not understand what Jefrs is on about. (But then I am only 68 years old and stripped down my first motorcycle engine when I was aged about 10.)

[jefrs]

So do I Peter, in fact the note emitted, like a guitar string, is proportional to the tension they're under. If they emit the same pitch ping, they're at the same tension. I rattle a spanner around them, no dead notes

[Dennis C]

There's a lot of stuff on wheel building out there in lala land but it never beats first-hand experience. That's true jefrs, and I think that having been building wheels for over fifty years I may just have that first hand experience?. So far this year I have only done 10 so possibly I am beginning to loose that experiance but the people I have built them for are all very happy with my work so maybe not.

[PeteF]

Jefrs, as a musician and singer of some 20 years I do know about the relationship between string tension and pitch (and string gauge, but we won't get into that)
My point is, if spoked wheel flexed in the way you describe, then the weight of the machine would increase the tension on the top spokes while decreasing the tension at the bottom. I can discern no trend towards that in the pitch obtained by tapping the spokes. This is despite being blessed with very good relative pitch.

[Bet]

Tried my hardest to get 'flex' on my rear wheel, oops, bike fell over.If I had any play I would get it seen to fairly pronto.