The journey to homemade rope spoke started all the way back in 2018shortly after the company Berd introduced their very expensive rope spokes. Berd’s spokes are made from a hollow woven rope of ultra-high molecular weight polyethylene (UHMWPE) with very low creep. They claim that wheels are stronger than steel spoke equivalents and have a fraction of the weight. Naturally, forum users wondered, “Why can’t we make our own?” It turns out there are a handful of problems with trying this at home.
There are a number of ways to skin this proverbial cat, but they all revolve around some very special nautical ropes, namely: Roblijn DM20. This rope has excellent wear and creep properties, in a hollow weave, similar to what Berd has developed. The hubs also require the addition of a bevel around the spoke holes to prevent wear. In addition to these two similarities, there are quite a few ways to thread the spokes between the hub and the wheels.
As detailed by [Ali Clarkson]One method involves making loops from bicycle spokes, using a custom mold and some soldering. A piece of rope is then passed through the hub and a special clevis is used to hold it in place. Two loops are made at the ends of this piece of rope and passed through the previously made spoke ends. Finally everything is tensioned and aligned just like a normal wheelset. The front wheel ended up weighing about 700 grams, a pretty impressive feat for a 24-inch downhill wheel.
However, a number of other methods have been tried in the forum threads. A number of users have tried, with varying degrees of success, to place a piece of spoke in the hollow rope weave and catch it with a “Chinese finger”. The main problem here is finding an adhesive that is strong enough to hold the spoke piece at lower tensions, but flexible enough not to crack from the cyclic loading on a rim.
Ultimately, this is a great look at the properties of an extremely special rope. This isn’t the first time we’ve seen strange bicycle wheels made with UHMWPE either.
#Bicycle #spokes #rope