Just measured the spoke tension on the wheels that came on my 2018 Whyte 909. The average (disc side) on the front were 137kgf. WTB recommend a max 120 for the rim. No wonder there have been a lot of spoke hole cracks reported with their wheels. Beware machine built OE wheels!
Not really machine building to blame there. Machine or hand built if it’s not set properly it’s not going to work. You’re right about Whyte wheels though, for years they’ve seem to have been either ripping the rim apart or the spokes have just gone floppy instead
I suspect it's easier to set a machine incorrectly rather than hand tensioning most of the spokes too high. You'd have to be a pretty incompetent wheel builder.
That's not a massive difference, <10%.
How sure are you of the accuracy of your tension meter?
That and do WTB measure it with or without the tyre inflated?
I'm using a new Park TM1 meter so I presume it's well calibrated. I entered the readings into their wheel tension app.
I think rated tension is based on tyre off, and assumes some loss of tension once tyre on? (honestly can't remember, makes more sense than trying to build your wheels with the tyres on though!).
So 137 with tyre on would be even higher than it seems as that would be (complete guess) 145 with tyre off i.e. how it should be measured?
I would have thought most rim manufacturers are quoting max tension with tyre off as the numbers are important reference points for wheel building.
I measured 137 with tyre off BTW. And to the point above "it's only less than 10% over", surely if it's over, it's over and asking for rim failure?
The tool you are using is only really a comparison guage, unless you have taken a spoke out and measured deflection at tension first? Any charts are only a ball park, spokes are manufactured to tolerances.
What are you trying to prove, checking a new wheel?
Were the spokes equally tensioned?
What are you trying to prove by checking a new wheel?
Not a new wheel. One of the original ones that came on my bike. My rims cracked at the spoke holes so I'm trying to find out why. The spokes are evenly tensioned (within 20% range, bar one spoke, which might have detensioned over riding time).
I’m using a new Park TM1 meter so I presume it’s well calibrated. I entered the readings into their wheel tension app.
I've got the same tool, as mentioned previously it's a good guide, but isn't what anyone would call accurate. You could get +/-50% just by adjusting how slowly you release the lever!
Not just a Whyte problem though, everyone seems to be making cracking rims these days, mostly down to the fact that people demanded rims be 60g lighter without eyelets rather than last more than a couple of years.
I’m using a new Park TM1 meter so I presume it’s well calibrated. I entered the readings into their wheel tension app.
The numbers on the scale may as well be pints of milk or rocks. They have no real meaning in life.
Tension meters are good for proving consistency and not much else.
The value you read will as mentioned, change depending on how quickly you release the lever, where you measure on the spoke, the butting and so on.
Some wheels seem to be badly designed so that in order for the rear non-drive side spokes (or front non-disc side) to be tight enough that they don't loosen themselves off the drive side spokes have to be so tight they kill the rims. Basically too much dish. Can be remedied by using asymetric rims.
What's the real measurement here? Presumably they don't pung or pong but is it a ping, a PING, or a ting?
Some wheels seem to be badly designed so that in order for the rear non-drive side spokes (or front non-disc side) to be tight enough that they don’t loosen themselves off the drive side spokes have to be so tight they kill the rims. Basically too much dish. Can be remedied by using asymetric rims.
Yup, I don't think it's actually possible to build a stans 29er rim within the spec. It kinda works with 1.5mm spokes. In the end I just added about 10% to the tension and threadlocked the nipples.
I'm not sure why asymmetric rims aren't more common. An asymmetric front rim would be considerably less offset than a symmetrical rear rim is.
I don’t think it’s actually possible to build a stans 29er rim within the spec.
Interesting that the new stans mk5 rims are asymetric too...
No doubt you've checked tensions on other wheels to compare if they are over tensioned or its the meter, makes you wonder what the tensions were when new, but some people will get snarky and argue about anything on here.
If theres cracks around the holes I'll suggest your assessment is correct and credit you with some intelligence rather than assume you're a numpty.
Factories commonly tension to a level a bit over the WTB rims limit of 120 - so over-tensioning may be the case. They don't always reset the machine for every batch or rim type/brand and it needs keeping tabs on. I'm not saying Whyte got this wrong, I just know from experience that it happens.