I brought a Coker into my LBS – I’d like to get the spokes tightened, but they want to know what tension the spokes should be. I’ve only found discussion regarding U-Turn’s wheels – any common tensions among the Airfoil/Suzue combo crowd?
Thanks,
Joel
Which spokes do you have? The stock Coker spokes or the custom stainless steel spokes from The Unicycle Factory?
With the stock spokes the tension is going to be less than with the stainless steel spokes.
Good question: I’ve got the Coker Deluxe that uni.com offers – 2001 model – since I haven’t heard of UF spokes before, I imagine I have the stock spokes.
U-Turn’s discussion about Coker spoke tension was with the stainless steel spokes. That kind of spoke tension isn’t going to be possible with the stock Coker spokes. Unfortunately, I don’t know how high you can go with the stock spokes and an Airfoil rim.
Ping! Here’s hoping someone notices this thread who can help me out – my legs are cramping with anticipation.
Thanks,
Joel
Tension / spoke wrench
Thanks for this thread. I just re-built a Coker wheel for a MUC club member (installing an Airfoil) and I’m finding that my spoke wrech is so sloppy on the nipple that I’ll strip the nipple flats before I get enough tension - even with the standard spokes. Does anybody know if Park or Pedro (etc.) makes a spoke wrench in the right gauge for the Coker spokes?
Tommy
Re: 36" Airfoil spoke tension
Assuming that your spokes and the hub flanges can take it, the limiting tension in any tensioned wheel is reached when the rim is near the compressive buckling failure point; i.e., almost ready to self-taco.
The only real difference between a U-turn wheel and the Suzue wheel is in the spacing between the hub flanges. I don’t have a quantitative theory to help, but this simple thought experiment might be useful.
Imagine that you could magically vary the flange spacing without changing the spoke tension. Yes, this means that the spokes would be changing length while under constant tension, but hey, that’s why it’s a magical change.
Now increase the flange spacing to, say, 3 feet. The spokes now make a 90 degree angle at the rim and there is NO WAY the rim can taco. What happens when the flange spacing goes to zero? Then the rim is no longer supported laterally and, if the tension is high, it tacos instantly.
The Suzue hub is narrower, so the spokes can’t be tensioned as high as the spokes in a U-Turn wheel without tacoing the rim.
The mechanics ought to just do what they usually do with a new spoke/hub/rim combination - crank the tension up as high as they can and back off when weird things start to happen. That’s how U-turn came up with the tensions he uses.
You had me at “flange.”
Flanges are the disk-like parts of the hub with all the spoke holes in them.
Sorry, thought this was an everyday term, as in “please pass the crackers that look like the flanges from an old-skool 1968 Campagnolo track hub,” but then again, I’m the kind of guy who spreads peanut butter with a peanut butter wrench.
hmm? no responce from U-turn yet…must a be secret formula.
taken out of context, that is one of the funniest things i have read in a while.
Re: 36" Airfoil spoke tension
“john_childs” <john_childs@NoEmail.Message.Poster.at.Unicyclist.com> writes:
> U-Turn’s discussion about Coker spoke tension was with the stainless
> steel spokes. That kind of spoke tension isn’t going to be possible
> with the stock Coker spokes. Unfortunately, I don’t know how high you
> can go with the stock spokes and an Airfoil rim.
Are you sure you can’t use the same tension? Overtension usually
results in failure of either the rim (either by deforming into a
potato chip or pulling through at the eyelets) or the hub flange, not
spoke failure. So I’d expect the correct tension top be independent
of the choice of spokes.
Park Tool company has this to say on the subject:
As a rule of thumb, it is best to set tension as high as the
weakest link in the system will allow, which for a bicycle wheel is
usually the rim. Therefore, to obtain a spoke tension
recommendation for a specific wheel, it is best to contact the rim
manufacturer.
[http://www.parktool.com/repair_help/tm_1.shtml]
On the other hand, Sheldon Brown’s wheelbuilding page says something
about choosing tension based on both rim and spokes, but doesn’t offer
details. It is possible that’s because spoke tensiometers read
different values for the same tension on different kinds of spokes.
Ken
Re: 36" Airfoil spoke tension
“john_childs” <john_childs@NoEmail.Message.Poster.at.Unicyclist.com> writes:
> U-Turn’s discussion about Coker spoke tension was with the stainless
> steel spokes. That kind of spoke tension isn’t going to be possible
> with the stock Coker spokes. Unfortunately, I don’t know how high you
> can go with the stock spokes and an Airfoil rim.
Are you sure you can’t use the same tension? Overtension usually
results in failure of either the rim (either by deforming into a
potato chip or pulling through at the eyelets) or the hub flange, not
spoke failure. So I’d expect the correct tension top be independent
of the choice of spokes.
Park Tool company has this to say on the subject:
As a rule of thumb, it is best to set tension as high as the
weakest link in the system will allow, which for a bicycle wheel is
usually the rim. Therefore, to obtain a spoke tension
recommendation for a specific wheel, it is best to contact the rim
manufacturer.
[http://www.parktool.com/repair_help/tm_1.shtml]
On the other hand, Sheldon Brown’s wheelbuilding page says something
about choosing tension based on both rim and spokes, but doesn’t offer
details. It is possible that’s because spoke tensiometers read
different values for the same tension on different kinds of spokes.
Ken
Re: Tension / spoke wrench
Park Tool make a good one: the SW-3 (blue handle) http://www.parktool.com/tools/SW_3.shtml
I bought one of these on George Barnes’ recommendation. No-one at the bike shop could tell me if it was the right size, so I just bought it, hoping it would be OK. When I walked out of the shop I saw that they had, of all things, a Coker wheel sitting in the window! I went back inside and checked the wrench on a Coker spoke nipple and it fit snugly.
t()||y
Thanks, Tony!
Tommy