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Banned Sock Puppet
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Discussion Starter #21

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Banned Sock Puppet
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Discussion Starter #22
if you have lots of wheels, road and mtb, especially mtb, you should at least know how to true a wheel. Because mtb wheels, especially the rear, will go out of true if you ride them hard enough, I don't care if you use 32h, unless your landing is perfectly perpendicular to the ground every single time, you'll knock them out of true eventually. I haven't built any wheel (too much effort), but trueing a wheel is almost a necessity for me, else I'd be in LBS constantly
aclinjury, most road wheels aren't subject to the abuse that you give your MTB wheels. As seldom as pmf needs a true and as busy as he is, it probably makes more sense to pay his bike shop the $10-20 they charge to true a wheel once in awhile.

All my wheels I have built including a pair with 7000 miles on them are just as round and true as the day I finished building them.
 

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Just completed my first wheel build , had a rear wheel ( Easton R90sl ) that developed cracks around 3 spoke holes . Figured it was time to give it a go as I have always wanted to attempt it .
Bought the Musson book online and built his dishing gauge with some minor modifications and also used his info for a nipple driver. I have had a truing stand for quite a few years . Purchased the park tool TM-1 and had a go at it.
End result turned out not too bad , plotted the tensions on the park tool tension app and managed to get the spokes to 10% equal tension.
Have only rode them once as winter has showed up, came back as true as when I left. Only time will tell now. I found it interesting and may try building a set in the future but it probably is just as cheap to buy prebuilt.
 

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Banned Sock Puppet
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Discussion Starter #24
Just completed my first wheel build , had a rear wheel ( Easton R90sl ) that developed cracks around 3 spoke holes . Figured it was time to give it a go as I have always wanted to attempt it .
Bought the Musson book online and built his dishing gauge with some minor modifications and also used his info for a nipple driver. I have had a truing stand for quite a few years . Purchased the park tool TM-1 and had a go at it.
End result turned out not too bad , plotted the tensions on the park tool tension app and managed to get the spokes to 10% equal tension.
Have only rode them once as winter has showed up, came back as true as when I left. Only time will tell now. I found it interesting and may try building a set in the future but it probably is just as cheap to buy prebuilt.
10% is about as good as you will do with the Park Tool TM-1. Why is that? Well, believe it or not, a spoke is not absolutely straight - not even at full tension. Spokes have irregularities that are enough to affect your measurements with the TM-1.

About a year ago, I bought this tensiometer:

https://www.wheelfanatyk.com/store/digital-tension-gauge/

Not cheap, but they way it measures factors in these irregularities. This being said, I built wheels with the Park Tool TM-1 and even with up to a 10% error, none have gone out of true including the ones with over 7000 miles on them.
 

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10% is about as good as you will do with the Park Tool TM-1. Why is that? Well, believe it or not, a spoke is not absolutely straight - not even at full tension.
Any idea if this issue is minimized using straight pull spokes? I realize that straight pulls also aren't absolutely straight, and they present their own problems. But is it easier to get more consistent tension with straight pull?
 

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Banned Sock Puppet
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Discussion Starter #26
Any idea if this issue is minimized using straight pull spokes? I realize that straight pulls also aren't absolutely straight, and they present their own problems. But is it easier to get more consistent tension with straight pull?
I don't see how this would make a difference regarding the area where you are measuring tension. The variation I was describing is due to imperfection of the spoke surface. The only advantage (theoretically) to a straight pull spoke is eliminating the weakness at the j-bend.
 

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Any idea if this issue is minimized using straight pull spokes? I realize that straight pulls also aren't absolutely straight, and they present their own problems. But is it easier to get more consistent tension with straight pull?
Short answer: no. Regardless of the "path" the spoke takes, assuming the spokes are uniform then the thing that causes inconsistent tension is much more likely to be variations in the rim, and possibly in the hub flanges. The force on the spoke, and therefore the tension, is a result of these external factors and not of any slight bends in the spoke.
 

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Short answer: no. Regardless of the "path" the spoke takes, assuming the spokes are uniform then the thing that causes inconsistent tension is much more likely to be variations in the rim, and possibly in the hub flanges. The force on the spoke, and therefore the tension, is a result of these external factors and not of any slight bends in the spoke.
I would think the biggest contributing factor would be each spoke binding and dragging the nipple a different amount, creating false and slightly unequal tension. Not the imperfections in rim and hub tolerances.

And back to my original question, I would think that a J-bend may deflect a spoke more than a straight pull. I'd go downstairs and look at my bikes to compare, but I had surgery on my hip last week and I'm upstairs for the night.
 

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I would think the biggest contributing factor would be each spoke binding and dragging the nipple a different amount, creating false and slightly unequal tension. Not the imperfections in rim and hub tolerances.

And back to my original question, I would think that a J-bend may deflect a spoke more than a straight pull. I'd go downstairs and look at my bikes to compare, but I had surgery on my hip last week and I'm upstairs for the night.
That might well be what you would think, but that doesn't make it so. An old wheel builder's trick is to put a touch of grease on the shoulder of the spoke nipples so that they turn easily in the rim and align as well as they are mechanically able to do. Even with this, and with grease on the nipple threads, you will get differences in spoke tension that can only really be explained by rim/hub flange variations. With good quality rims and hubs there is not much variation in spoke tension.

There is spoke deflection with J-bend spokes where they come out of the hub flange, but that is not in any way an issue nor is it a source of variability in spoke tension. +Quality spokes are very uniform one to the next.
 

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Banned Sock Puppet
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Discussion Starter #30
That might well be what you would think, but that doesn't make it so. An old wheel builder's trick is to put a touch of grease on the shoulder of the spoke nipples so that they turn easily in the rim and align as well as they are mechanically able to do. Even with this, and with grease on the nipple threads, you will get differences in spoke tension that can only really be explained by rim/hub flange variations. With good quality rims and hubs there is not much variation in spoke tension.

There is spoke deflection with J-bend spokes where they come out of the hub flange, but that is not in any way an issue nor is it a source of variability in spoke tension. +Quality spokes are very uniform one to the next.
Grease or oil? Most wheel building sources I've read say to put oil inside the nipple bed of the rim.

And while I won't argue that rim and hub flange variations could impact spoke tension, I still maintain that variations in the spoke surfact will impact readings too. Not sure exactly how to explain that, but if you have ever used the K&P Lie tensiometer, it is apparent this is the case.
 

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Grease or oil? Most wheel building sources I've read say to put oil inside the nipple bed of the rim.

And while I won't argue that rim and hub flange variations could impact spoke tension, I still maintain that variations in the spoke surfact will impact readings too. Not sure exactly how to explain that, but if you have ever used the K&P Lie tensiometer, it is apparent this is the case.
Grease is a lot more durable than oil. I go by feel and sound for tension.
 

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Banned Sock Puppet
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Discussion Starter #32
Grease is a lot more durable than oil. I go by feel and sound for tension.
Many good wheel builders indeed go by feel and sound. The problem I find with these is they are very difficult to quantify if measuring tension on many spokes at a time. I am more mathematical and need to see numbers.
 

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Sure it counts. Do tell. Details!
It was the rear of this wheel set I modified. It went from 6 pawls to 3 after feeling that there's little too much drag.
021321-1.JPG 021321-2.JPG

Then I was going to change to winter tires but after seeing the forecast and how well the roads are plowed, I decided to keep the regular tires (it's almost March).
 

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Russian Troll Farmer
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It was the rear of this wheel set I modified. It went from 6 pawls to 3 after feeling that there's little too much drag.
View attachment 478576 View attachment 478577

Then I was going to change to winter tires but after seeing the forecast and how well the roads are plowed, I decided to keep the regular tires (it's almost March).
.....But.....but.....now you've doubled the load on each remaining pawl. I'm imagining the day you come up to a REALLY steep hill; you'll be out of the saddle pumping with all your might......then.....the freewheel mechanism fails, you go over the bars, and land hard on the pavement, cracking your new helmet....
 

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Banned Sock Puppet
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Discussion Starter #35

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I'm imagining the day you come up to a REALLY steep hill;
Thanks for the concern. I'm in Midwest where it's as flat as pancake. Plus, it's my beach cruiser bike which I use for short leisurely low speed ride.
How many watts do you expect to gain by eliminating 3 pawls?
Most freehubs I see on the market come with 3 pawls. It's not for gaining the wattage during coasting but for the convenience when backpedaling to get one foot at 3 o'clock position at a stop. It had just enough of drag to cause chain drop and gave me greasy fingers bunch of times. 🤬
 

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Banned Sock Puppet
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Discussion Starter #37
Most freehubs I see on the market come with 3 pawls. It's not for gaining the wattage during coasting but for the convenience when backpedaling to get one foot at 3 o'clock position at a stop. It had just enough of drag to cause chain drop and gave me greasy fingers bunch of times. 🤬
If your pawls are causing enough drag to make you drop your chain when backpedaling, you have a different problem. And I kind of doubt that extra little bit of pawl drag is what is causing your chain to drop.

The only advantage I can see to reducing pawls is your freehub will be quieter.
 
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