Wheel wizards….advise
 

I have a set of titan wheels from performance. They use bladed spokes and have 20 spokes in the rear wheel. There is a 2 cross pattern and 10 spokes on each side and the spoke fits into the 1.5 park tool spoke measurement slot thing. I have heard a lot of creaking from the wheel and I read here that it may be due to wheel tension. So I got a Park Tool TM-1 to check it out after the guy at the shop said he would charge me to tension it for $45. Why not…better than sitting in front of the TV…

Ok so here are the readings…

Right side:
17
21
19
19
19
21
18
19
19
21

Left side (non drive side)
13
10
15
12
13
7
16
12
10
14

I can tell it is tension problems…cool but now what???

I’m reading the stuff here http://www.parktool.com/repair/readhowto.asp?id=51
But I’m a bit confused as to how to get the numbers I need for the right and left side….

Is there any shortcut or is it this involved?

is your rim symmetrical or asymmetrical? Spoke tension is generally different from left to right on rear wheels because of the shortened spokes on drive side for a symmetrical rim. You should talk to Performance about the building specs of these wheels from the lacing, tensioner...and take it from there. Using a tensioner without a tension number to reach is like using a torque wrench with no specs to achieve.

That's a lot of tension variation. You have one spoke on the non-drive side, for example that has only about half the tension of the others. That's clearly unacceptable so you know that you have to do something. The question is what.

On a traditional wheel with round spokes you'd be looking for around 100kgf. On a wheel with fewer spokes you'd want that tension number to be higher. A bladed spoke, however, is going to deflect a little less on the tensiometer than a round spoke so just dialing the tension up to the gauge reading for a 1.5mm round spoke will be too much. In other words, you don't know what the tension spec for each spoke is but, even if you did, you wouldn't what gauge number on your tensiometer corresponds to it.

Here's my GUESS:

I'd bring all of your drive side spokes to 19 on your tensiometer. I picked 19 because that's what most of them are now. I'd bring the non-drive spokes to 14 or whatever number is necessary to get the dish about right on the average. Then I'd true the wheel by tightening and loosening opposing pairs of spokes the same amount.

Good luck.

Well, the back side of the TM-1 conversion chart has bladed spoke numbers, so a true kgf reading should be possible. I'd agree with 100kgf or more, and recommend going up to 110kgf. Note that if you contact Performance, they should be able to tell you the tension spec for the rim. I'd call them (rather than email or interactive web help).

+1 (substituting 19 for whatever the conversion is for Performance's spec)

If you can't wait for Performance, go with 19. I wouldn't ride this wheel until you you get it retensioned, just in case you hit a big bump on accident near that 7 spoke :eek:

I went with 19 for drive side and 14 for non drive side...the wheel is now true and I will test it out on the rollers...called performance but was on hold for too long....will call back

thanks guys...we will see how it goes...

That wheel is a Neuvation M28 Aero. Performance just has them made by them under their Titan re-branded label.

On the drive side you go with 19,but what if you have disk brakes.Would you go with 19 as well.Not trying to steal the thread but I just ordered the same tool.Thanks George

based on what I am finding out...call the maker of the wheel and ask for the numbers....

I hope you get that info...if not you have to check your wheel right now and get an avg. ...if you use the X-cell sheet it kind of helps get an idea...see the link above and down load and fill it in...a long read and not too clear...but it helps...at least you will know what you don't know and what you then need to know...

http://www.parktool.com/repair/readhowto.asp?id=52

let us know what you find plz....

All the information about this wheel and a similar wheel that used to be sold by Supergo indicates that they are not an exact copy of the Neuvation M28 Aero. There may be differences in the spokes used (size of root end etc) and the method of building.

But if the rim is the same, that's what determines recommended spoke tension...

I think the spoke and rim and hub all play into it...the better the stuff...i think....means more rension is cool....

Supergo Korso, Performance Titam, Nevation M28 Aero .. pretty much same difference. Oh maybe Neuvation might use slightly better grade parts, but that's about all. Just like Performance Gemini wheels are Alex 300s. Tension is tension, mate.

I also sent performance a e-mail...

I just found out today that when you call Performance,that Performance and Nashbar are one.Anyhow they didn't know anything.So I called WTB who made my wheels and they said,work toward 120.I don't have my meter yet, but I think that's pretty close to 19 or 20.They said it would be almost impossible to get the same reading around the whole wheel. I really not trying to get the same reading all around, but I hope to be within reason. I hope this helps a little,George

Don't forget to remove tire pressure when checking tension. But you probably already know that.

My wheels all have less than 5% tension variation when I build them. It's not hard, but my wheels are conventional spoke counts, not low counts -- which will make it a little tougher.

I called and e-mailed performance bike...they did not want to give me a number...they just said...if you feel that they are not safe...return them and get a new set..

cool but kinda not cool at the same time....lawyer fear may be to blame...

yep...you have a bit of room for an average...see the park tools site and download the x-cell sheet..

enable micros and it will do the math and tell you what spokes are off...it does it in a range...kinda cool if ur a nerd...

You should be able to take the drive side rear up to 21-22 no problem. Set the non-drive rear to balance the drive side.

Now that you have the tension gauge, check the tension in the spokes every few months or so to keep track.

what are the units and what are the spoke dimensions? Not enough info.