Sturmey Archer Hub Brakes

[Brucey]

result! It just shows that it is always worth trying the most straightforward things first.

cheers

[iandusud]

Yes,I suppose the tube was acting as a spring. What are your thoughts on the wheel build. I like to keep the spokes as near to a tangent as poss with the drum brake but don't like the look of the bend near the nipples.

[Brucey]

I would probably build that wheel x2 but I have also seen this sort of wheel built x1. If necessary I might modify the rim so as to reduce the nipple kinks.

Maintaining tension in a wheel like this isn't always easy; the slightest settling of the spokes at either end leads to the spokes going almost completely slack. The difference between full tension and no tension can be as little as 1/2 turn.

cheers

[iandusud]

What did you have in mind re modifying the rim?

[9494arnold]

You can always use small washers at the hub end of the spokes, it won't make the exit angle any different but it can stop the hub abrading the spoke and bringing on spoke failure. With a hub brake the spokes are working a bit harder methinks, particularly if you have a load on.
The only way I can think of reducing the angle of the spoke is having offset spoke holes (if you don't already) , most reasonable quality rims have this and with a double wall the nipple bed in the rim is slightly angled too, or at least appears to be. In fact I have seen wheels built with washers under the nipple too.

[iandusud]

The spoke holes in the rim are offset and eyeleted but not angled.

[Brucey]

What did you have in mind re modifying the rim?

some eyeleted rims (eg sputniks) can have the eyelets 'tweaked' to a new angle and this reduces the nipple kinks. Other (non-eyeleted) rims can be angle-drilled oversize and then 'converter' nipples (13g body, 14g thread) or full size 13g nipples can be used, if necessary with washers under the nipple. So for example the standard front rim on some bakfiets models is a 20" Ryde Andra which has been angle-drilled for 13G spokes/nipples. [tbh I don't know if Ryde do this or it is done by a third party, but that is how they are when they are fitted to a bakfiets.]

For many years a standard tandem rear rim would be a super champion Mod58, drilled out to accept 13g or even 12g nipples, again seated on washers. In this case the original (single) eyelets are removed and the rim is only stopped from cracking in service by the use of the washer under the nipple.

Spoke washers at the head end are (for me anyway) SOP if the fit is in any way slack, which it very often is. In fact I think wheels normally end up being better wheels if the fit is a bit tight and you have to work a bit to seat the elbows in the flange.

cheers

[iandusud]

Will eyelets stand being drilled and can they be tweeked by putting a rod in and applying pressure?

[Brucey]

once you start drilling eyelets they are destroyed/removed.

The 'tweaking' is exactly as you infer; inserting a close-fitting tool and giving it a bit of persuasion can reset them to a better angle, provided they are a slack fit on diameter it works OK, but they are not all like this.

cheers

[iandusud]

Thanks Brucey, I'll give that a go.

Ian

[iandusud]

I've tweeked the eyelets using a torx wrench (don't remember what size off hand) that was a lovely tight fit in the eyelets. The nipples line up nicely now and I can keep the 3 cross pattern, which I prefer considering the torque of the drum brake and the fact that it makes for a longer spoke.

Cheers, Ian

[Brucey]

good work! Any photos?

cheers

[elPedro666]

What a great thread to stumble on, and a fantastic project [emoji41] 70mm SA drums will just about pull stoppies on my very short 80s mtb, but it's the fact that they basically never lock up which endears them to me so thoroughly. I imagine this makes them ideal for your application.

Thanks for the build pics and I look forward to more updates on your progress!

I'm a trendy consumer. Just look at my CLT-L09 using hovercraft full of eels.

[iandusud]

good work! Any photos?

cheers

Here you go, with the addition of a mudguard.

https://drive.google.com/open?id=1UBp6E ... cHac_eCHF8

I've also shortened the front steering link to make the steering less sensitive with good results.

https://drive.google.com/open?id=14u6s0 ... oa9XeH17qc

[Brucey]

for some reason I can't see your pictures; is this a computer problem at my end or are others in the same boat?

cheers