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Certifried
11-12-2012, 02:43 PM
I bought this fancy little spoke tensiometer along with the truing stand I got. I've finally figured out how to make it all work, but am having difficulty finding the proper spoke tension. The rims are Alex Rims DC25. The spokes are steel. Nothing fancy about them, they're 2.0 mm according to the gauge. I can't find anything specifically for these rims, so I'm wondering if there's some general numbers I should be shooting for.

thecyclingeconomist
11-13-2012, 07:50 AM
Which tension meter are you using? If you are using the Park-tools, then they should have provided a chart. Every spoke/lacing pattern has different tensions. Also, for a clydesdale build you want to run the tensions at the top-end as I'd mentioned a bit ago.

Certifried
11-13-2012, 08:25 AM
Which tension meter are you using? If you are using the Park-tools, then they should have provided a chart. Every spoke/lacing pattern has different tensions. Also, for a clydesdale build you want to run the tensions at the top-end as I'd mentioned a bit ago.
Yes, it's the Park tool one. So all those numbers on the chart are the recommended range? I thought it was just a conversion chart from what the tension meter reads to kilograms force. For a 2.0mm spoke, the range they list is from 53Kgf to 173Kgf. That's a pretty wide range, so was specifically trying to figure out what my rims should be at. Yes, I'm a clyde, and I put a lot of extra weight on the bike too (rack, full pannier, etc**).

I can't find anything on Alex Rims website for the DC25 spoke tension, but there are other rims listed there. Many of the spoke questions they have are answered with "we don't know, we send it to the bicycle manufacturer who put their own spokes in". So, I've emailed Jamis to see if they can answer me. Currently, the readings I was getting are all around "22", which is around 86Kgf. The range the chart has listed goes from 53Kgf to 173Kgf.

** I just realized I might want to balance my load. I was using 1 pannier because the second pannier seemed needlessly heavy if I could fit everything in one. I don't have a problem with the bike being off balance, but now I'm considering the force I'm putting on the back rim. I might need to balance it....

Dirt
11-13-2012, 08:39 AM
I'll chime in here... but I'm not going to be a lot of help. I've been building wheels for 40 years and do it mostly by feel. I use my Park spoke tension tool to check that things are generally even between the spokes. I really use it at all for truing wheels.

I've never looked for, nor seen any information on specific spoke tensions for particular rims, though the rigidity of the rim has something to do with the whole equation.

The range on the Park spoke tension chart is quite wide because there are many different ways that you can build a wheel with the given spoke thicknesses. There are many, many factors that go into how much tension to put into a wheel that it would take a pretty good spreadsheet to really give you a closer approximation. Things like number of spokes, cross pattern, flange diameter, spoke length, style of rim (rigidity), etc.

Some things that I do NOT take into account very much when choosing spoke tension is weight of the cyclist and what they're carrying. That helps me pick the parts that I use to build the wheel more than the actual spoke tension.

I'm sure there are some smarter people out there who can be more precise than this.

Informative answer? Perhaps. Helpful? Probably not.

Rock on!

Pete

off2ride
11-13-2012, 11:06 PM
My tension meter are my fingers and hearing. Here's the ghetto way that works to verify good tension...tap the each spoke close to the nipple on the truing stand and compare the "ding" sound. They should all sound ALMOST equal.

thecyclingeconomist
11-14-2012, 09:04 AM
My tension meter are my fingers and hearing. Here's the ghetto way that works to verify good tension...tap the each spoke close to the nipple on the truing stand and compare the "ding" sound. They should all sound ALMOST equal.

That's actually not that "ghetto" at all... many builders used to (some probably still do?) use tuning forks to determine whether spoke tensions were even around the wheel... Just know that if you do this, the drive and non-drive side spokes on the rear wheel are VERY different. The drive-side run 30% higher tensions than the non-drive (or more) depending upon the hub and each side's center to flange measurements. So, the drive side should have a much higher pitch than the non-drive, but on each side the sound should be consistent.

The problem is: you can have a wheel that has consistent spoke tensions (they all sound the same) that are simply too low (which is what Certifried was dealing with that started this all off)

For a Clydesdale build, I'd run around 130 kgf (kilograms of force) on a front wheel's spokes, and about 175 kgf on the drive side rear (this is ballpark, and depends upon the wheel material, spoke used). When using your tension meter, make sure to place it in the center of the spoke (not too close to the hub, or the rim), and always measure at the same place as you move from spoke to spoke.

Good luck!

(Just found this link for you: http://autobus.cyclingnews.com/tech/fix/?id=tm_1)

thecyclingeconomist
11-14-2012, 09:14 AM
Some things that I do NOT take into account very much when choosing spoke tension is weight of the cyclist and what they're carrying. That helps me pick the parts that I use to build the wheel more than the actual spoke tension.

Definitely agreed that weight/load determine the materials first: and that's why I run most of my wheels as 36-hole 3-cross. But, if you are still breaking spokes regularly, then you can move to a tandem rim (like a velocity dyad or something of the sort)... if still breaking spokes, then it's most likely the tensions...

I'd say that's why the initial build/correct initial tensions (high enough, consistent, well-seated into the hub (correctly side-tensioned)) are so important. I built a wheelset with ultegra hubs and velocity aerohead rims in a 36 3-cross setup, and I honestly never had to true the wheels for over 6K miles of riding (when I sold the bike). (And I am super nutz about keeping my rims true so that I can run my brakes with VERY tight clearance. I like my brakes to engage almost immediately when i compress the levers.)

Certifried
11-16-2012, 08:24 AM
Thank you!

I did get a response back from Jamis, which was basically what has been said here.

Thank you for contacting the support team at JAMIS Bicycles. There is no exact number that is correct in terms of spoke tension. Most wheels have a range of tension that they are designed for depending on the spoke, how the wheel is laced and other factors. Please contact your local JAMIS Dealer and they will be able to assist you further.
And they listed my local dealers. Initially I was a bit perturbed by this softball response, but I get where they're coming from. I also think it's great that they listed all the dealers for me, that helps to support the LBSs.

I think what I'll do is to start off slow, just make sure they're in the same range of each other. Get a feel for measuring the tension accurately, then start playing with the truing, minor adjustments at first. Just to get the feel of how everything works together. My wheel is back from Jamis, it was a defect of some sort, so I'll get the new wheel put on. Everything will be pretty true and correct (Proteus mechanics are awesome), so I'll make minor adjustments as needed. Hopefully by the time anything is WAY out, I'll be comfortable enough to get it set right. I also have the rims off that Miyata that's sitting on my wall rack, so I can play with that rim all I want, as it's going to be a while before I build that up.