[alanm]

HHHEEELLLPPP

I've muffed up the calcs for the spoke lengths for lacing my Rohloff into my Clownshoe on my Moony. I used Freespoke, with a 2 cross lace, and the calculator came up with 238.7 and 240.7. I purchased 240 as that was the closest any of the local shops had. Turns out they're too long by 9mm, quite substantially in other words. Does anyone know the correct lengths before I toodle off to town and depart with more cash. It just so happens town is 300Km away as well!!!!

BTW, whats the best spoke calc tool on the web?

Thanks in advance.
Al.

 

[alanm]

Turns out I didn't muff it up. The LBS gave me 245mm spokes instead of 240mm I've ratted through my old wheels and have found some 237mm spokes so will use them in combo with the 245mm, which I'll probably have to file down once they're installed, and see how close the offset will be. I guess in reality, it doesn't matter if it's a couple of mm out, because by the time I allow for all the wobbling around on the track the tyres are rarely truly inline anyway....... !!!

Al

 

[Canoe]

As part of your wheel building, do you stress the wheel to set the spokes & nipples?

 

[blown240]

Lace it as a 3x and you will probably use the extra length, plus end up with a wheel that's slightly stronger.

 

[alanm]

Canoe, Mate, I just build it up, ride it for a while and then retension as required. Works for me.

blown240, is that a blown 240 cube on the pushbike???? That I'd like to see!!!! I think there is something not quite kosher about lacing a Rohloff 3 cross, don't quote me, but I seem to remember reading that somewhere. Something to do with loading the flange too much and cracking it if I remember correctly.

OK, what I did was rat around in my man cave, (old caravan I use to store my bike gear in) and found some 237mm (used on drive side) and some 239mm (used on non drive side) spokes, both Sapim, but not double butted, but with brass nipples, beggers can't be choosers!! I laced it 2 cross and low and behold it has turned out perfect, when I went for a ride the rear center line of the BFL is smack on line with the front, talk about pure luck......it's all ar*e no class in this workshop pal....

I've left the double chainring on the front and so have a chain tensioner to enable me to use the front rings. This is for when I'm towing my trailer. I used to have it set up as a manual on my other bikes (read, use hand to hoike chain over) but I'm getting lazy in my old age!!!

Pics of finished product. Only bodge is the worm drive hose clamp holding the torque arm in place. I have to order a torque arm like that used on a rim brake Rohloff. Due to how I've fitted my carrier, niether a monkey bone nor speed bone will fit on, I tried them....bugga.... I know I have the rim type torque arm somewhere but I'm buggered if I can find it..... :madman:

 

[2LO4U2C]

I think there is something not quite kosher about lacing a Rohloff 3 cross

You are correct, because the hub diameter is larger than average hub, with a 3 cross, the spoke is entering the rim at too steep of an angle.

From the Rohloff site:

Due to the increased diameter of the hub flanges and PCD of the Rohloff SPEEDHUB 500/14, the spokes need cross only two times but do so at roughly the same angle as a three cross lacing pattern on smaller flanged hubs. There is less load on the spokes because of the large flange PCD diameter and the hub flange is subjected to lower forces because these spokes pull further away from the axle center creating a better lever to pull the wheel around (torque = force x lever length).

 

[alanm]

2LO4U2C, thanks for that, I was sure I'd read that somewhere, didn't think of looking on the Rohloff site.... duh....

 

[blown240]

Good to know!

Alarm- my screen name came from an old supercharged Volvo I built.

 

[Canoe]

Canoe, Mate, I just build it up, ride it for a while and then retension as required. Works for me.

With a rohloff ($) in the mix, if your wheel build included a few cycles of stressing the spokes to set the spokes & nipples (also releasing any twist in the spokes) and retension/retrue, wouldn't that mean you don't have to revisit the wheel to retension/retrue, nor subject the spoke holes in the rohloff to avoidable stress or wear?

 

[alanm]

Canoe, Whilst I'm building the wheel up, I tend to grab the spokes and give them a bit of a reef and often I have to tighten and back off spokes as I'm no expert wheel builder, for instance, whist this rim is true laterally, it has a 'bump' of about 1mm over a 3 spoke section that I just can't knock out.....so I've done what any red blooded pushbike rider would do....put a tyre on it and gone for a ride....works great....will worry about it later....much later....because there is a dirty great fat tyre on the rim, it sucks up that sort of out of round.

I've laced this Rohloff into 4 different rims sofar and the spoke holes are still OK, surprisingly.... When I first started doing it I used to stress a bit about the whole thing, but I'm pretty relaxed about it now. I've done roughly 50 to 60,000 Km's on this hub, I don't keep precise records so let's say 55,000 K's. Based on a purchase price of 2K (I remember that bit....) It's cost me 0.363 cents / Km so this hub is now quite a cheap option, that's why I'm fairly relaxed about it. Mind you, having said that, I'd hate to wreck it, not only for the replacement cost but also, more importantly for me, for the sentimental value, this hub has taken me to some great places and enabled me to have some great adventures.....

Al

 

[Canoe]

wow
55K
Sure an example of why those are worth the investment.

Seeing an old hub and a casual 'throw it together', I thought you'd picked it up used and I was afraid you would be building a wobbly wheel that would be chewing away at the spoke holes on the flanges.

As your experience has given you such success, perhaps a bit more comprehensive "grab & reef" would mean you wouldn't have to revisit the tension, nor worry about the holes. I've only built one pair of wheels from scratch and rebuilt four or five more to save some bikes donated to a 'get them back out there' bicycle rescue program, but I found the "formal" procedure surprisingly easy to follow (but I still need a few pages in front of me to get it right), with surprisingly good results. I followed Musson's book.

55k
wow

 

[alanm]

Mate, funny you should mention 'formal' I've decided to purchase a spoke tension tool. Doing a bit of research into them at present. Just for kicks and giggles, I tried my tension wrench with this build....screaming failure.... I'll have a look for Musson's book, I've not heard of it.

Al.