Calculating Spoke Length for HED Rims - Advice please

[fluroforks]

Well done that man!!! If ever i'm in Santa Monica I owe you one.

The M952 hubs measure the same so that's good news. Assuming the ERD's of both our rims are the same I think i'm good to go. Do you happen to know what it is on yours. If not I don't think it matters as I should be able to take some measurements of what I have here and alter the lengths accordingly.

Thanks again.

 

[syncrosfan]

I think the ERD on both should be the same. As far as I know the HED's use a SUN CR17 rim as their core. I did the research and the ERD of those rims is 545mm. Another member posted the same ERD in a previous post which leads me to believe that that ERD is correct. Now just to be sure I went to the spoke length calculator and checked the spoke length I would get for my front wheel and I got 267mm which is kind of what I measured (it looked like 266.5mm when measuring, so I said 266). based on those findings I would say you should be solid using the lengths I sent you. I didn't check the rear spokes because the front one checked out. I just calculated the spoke lengths for my Nuke Proof hubs and I was looking online what spokes I should use. I did find some DT titanium ones in gold that would be pretty cool, at a decent price too, but then again DT Revolutions are almost as light and still cheaper... decisions, decisions. Btw, DT do make some hex drive nipples (you'll need a 5.5 low profile hex driver to get in those holes though).

 

[fluroforks]

That is fantastically detailed information, its almost as if you've built them for me.

The only question I have now is what guage spokes are you using? I cant see anything on Sheldon Brown that advises what guage to use for this type of build.

 

[syncrosfan]

The spokes I have now are 15 gauge (1,8mm) straight (not butted, cheapo ones). Now I think you should be OK using any kind of gauge you want. I'm planning to use either DT revolutions for the re-lace (those are butted 2.0 to 1.5 to 2.0 mm) or the DT titanium ones (those are 2.0mm straight gauge). I don't know how much money you want to spend but since I assume you're not going to abuse those wheels you could definitively go for butted spokes, you could save some weight and the rims are not exactly light. Dt revos or Sapim CX rays are reasonably priced and light. (they come in black too).

 

[fluroforks]

Is there a reason that you haven't mentioned double butted spokes? I was reading elsewhere that some people prefer the double butted and others the single but some don't notice the difference. There is so much conflicting information on the web hat a novice like me gets very confused.

Assuming you've still got yours stripped could you tell me the length of the nipple?

I had no idea there was so much to consider when building wheels, i've laced a couple of pairs together in the passed but I always had the parts in front of me. That made it a lot easier.

 

[syncrosfan]

All the spokes nowadays are double butted. DT Revolutions for example are the double butted spokes. Single butted are rather rare and found on older style wheels, (a single butted spoke would be 2.3mm at the bend then taper down to 2.0 mm through the spoke all the way to the thread end). Usually when you say butted nowadays it already implies them being double butted. Now there are triple butted spokes like the DT Alpine (2.3mm at the bend, then 1.8mm through the middle, and 2.0mm at the thread) but those are usually used for high strength applications such as tandem wheels. The main reason to use double butted spokes is to save weight. I've had wheels laced up with DT revos and they held up just fine (I weigh well over 200 lbs.) so I honestly don't see any reason why you should use straight gauge spokes (other than cost...). If you want strength go for DT comp (2.0, 1.8, 2.0) if you want light go for DT Revolution (2.0,1.5,2.0). I don't know how much you weigh and what kind of abuse do you want to expose your wheels to, but there's usually no reason to make your wheels unnecessary heavy. What's more important for the overall strength of the wheel is even spoke tension! Get a Park Tool spoke tensiometer (they're not very expensive and get the job done, I use one). Take your time when lacing up and tensioning and try to get your spoke tension as even as possible.
The nipples are 11.5mm long. Brass chrome plated with a 5.5mm hex drive head on them (no slot). There are someT Swiss HexHead 2.0 x 12mm Silver Brass Nipples, Box of 100 on e-bay that come pretty close to the original. I think they have also an aluminum version of those if you want to save even more weight, however, since the rims don't have eyelets, I wouldn't suggest it as aluminum nipple on aluminum rim could lead to problems due to seizing.

 

[fluroforks]

At 230lbs i'm build for strength not speed! I think the wheels should be the same.

I'm not expecting to abuse them, theyll probably hang on the garage wall blinging up an RC200 but they will be used in the dry. Possibly an occasional trail centre but I think these will mostly be used on bridleways and UCR's.

You've covered everything I need so i'll get the parts ordered tonight and hopefully start lacing.

Out of interest have you ever taken the fairing off these? It must be possible and i'm wondering what to do when the rim wears out.

 

[syncrosfan]

I haven't tried to take the fairing off but I think it might be possible. The thing is: as long as the rims still make it nobody would want to risk destroying them. Would be interesting to pick up a pair for cheap (with destroyed rims) and try it with those first, basically you've got nothing to loose but maybe you can save a pair. I know some people have successfully swapped out alloy rims on the carbon fiber Spin wheels. I do have a batch of some kick-ass Loctite Hysol 9430 adhesive which is used to bond aluminum and carbon fiber together. If you know of a pair of the HED rims where the rim is destroyed for a cheap price I would be willing to give it a try to transplant the fairings to a new rim.
I'm thinking a DT Swiss XR 425 would be a far superior rim as it's base (still rim brake) but with proper eyelets and much better quality than the original SUN CR17 that were used.

 

[fluroforks]

Hopefully they wont get to the point of swapping the rims over but good to know its possible. I've heard of people using something similar to that loctite to stick roofs on land rovers. I ended up using a spot welder on mine.

All the spokes and nipples are ordered and on their way. This is quite a steep learning curve but well worth the effort. Keep an eye on my RC200 build to see the fruits of my labour.

Cheers buddy,

 

[syncrosfan]

What spokes did you end up ordering? Remember, an even spoke tension makes a strong wheel...
P.s. the RC200 is a sweet frame! (the only bike as cool as a Manitou HT). Good luck with the build!