.....I built this years ago; these days I expect I'd just buy an XT disc hub, much easier
Just what I thought when I saw the first photo,though it wouldn't work for the front.............
........but I nice Suzue one would
.....I built this years ago; these days I expect I'd just buy an XT disc hub, much easier
531colin wrote:Brucey wrote:531colin wrote: Yes, its 8mm less dish....-4mm left, +4mm right.....and the brake is 4mm off if you fit a "normal" wheel.....think about it!!
it does rather depend on how you define dish; I have always used the definition of the rim plane distance from the midpoint between the flanges, in which case it is surely 4mm less dish, not 8mm?...........
Nobody could argue with that!......I guess I must think of it as the difference in spoke angle/tension.....which relates to the difference in the flange to centreline distance.....doesn't it? getting late for me!
Ambler wrote:Does rim width make any difference to all these factors?
(apologies for novice question)
moonsafari wrote:http://www.chainreactioncycles.com/Models.aspx?ModelID=86123
moonsafari wrote:http://www.chainreactioncycles.com/Models.aspx?ModelID=86123
531colin wrote:Very interesting book. My copy is currently out on loan, so I can't refer to it just now, but I don't remember him actually quoting numbers for the extent to which Hi-Lo hubs reduced the tension difference?
Tony Oliver made his own roughstuff tourer with an offset back end and dishless wheel, which is what triggered me to get one built maybe twenty years ago.
I also used his preferred head angle/fork offset combination on that bike....it is the sweetest handling bike, and those numbers are still used for a certain titanium tourer.
However, there are some anomalies in the book....a whole chapter on steering geometry that doesn't mention the word "trail" ....?
531colin wrote:Jobst Brandt says that Hi-Lo hubs can reduce the tension difference by about 5%, but only if the spokes are fully radial. Edit....I think that should be radial driveside, left side tangential
teh wrote:My bike has a Shimano XT tandem hub, 40 spokes, and a FiR tandem rim. The hub was originally 145mm spacing, but it was a simple job to remove some washers and saw off some axle.
I weigh a lot, and my touring kit is heavy. This wheel gives me no problems.
Ribblehead wrote:
It would appear that 'trail' is labelled in Figure 3 on page 13. I don't think he actually discusses 'trail' in the text, but trail is a function of head angle and fork offset, so I think Figure 5 on page 15 more than makes up for the fact that he doesn't discuss 'trail'. For those who haven't read this excellent book, Figure 5 is a plot of Fork Offset versus Head Angle, on which the author plots the 'trail' of various different types of bikes (time trial, road racing, touring, tandem) and offers his opinion on the range of combinations which will result in a stable front end.
Ribblehead wrote:Although the Tony Oliver book includes a picture of a radially laced drive-side on a hi-lo hub (Figure 104 on page 115), the only tension values he includes are for a combination of 2-cross and 4-cross on drive-side and non-drive-side respectively. The tension values also show there is a benefit in differential lacing even when a hi-lo hub is not used. I have an old screw-on hub (not a hi-lo design) I intend to build into a wheel soon, so I may do some calculations to see if differential lacing would be advantageous.
531colin wrote: Hardly a ringing endorsement of Hi-los, unless I mis-understand.
531colin wrote:I struggle with figure 5.(got my book back).71 deg. 2 1/4 inch offset for touring....spot on, I think. But then he has less than about 1 1/2 inch offset 71 deg as "steering too quick", whereas his own fig 3 shows reducing offset gives more trail, (therefore more stability?). Same on page 16 in the text "If the rake is too short, the steering will be so sensitive...."
531colin wrote:You may have to help me here......my maths. is crap...... Page 114, fig 103(b)
Lots of examples, I'm going to take the 130mm OLN, as its the most up to date.
lacing 4x both sides, tension ratio 1: 0.879, whatever hub flanges.
Lacing 2x drive side, 4x left side. tension ratio 1:0.931 for small flange, 1:0.955 for large flange, 1: 0.962 for Hi-Lo
I make that about 6% better for the differential crossings on small flange.....about 2.5% extra benefit of L/F over small flange, and Hi-Lo offer less than 1% advantage over L/F.
Hardly a ringing endorsement of Hi-los, unless I mis-understand.
reohn2 wrote:With huge gaps and dodgy reliability issues.
reohn2 wrote:Deraileurs can more often than not be rigged for SS if necessaryin any gear until it can be repaired.
reohn2 wrote:Hub failure can = stranded.