Mopar440ci

Hey guys, i need some information befor i go out and buy the wrong thing.
im looking to rebuild my wheels on my roadbike to make them stiffer and more reliable and change the colors a bit in the process.
currently my bike is set up 24h radial spoke in the front 28h 2x spoke in the rear. im looking to set it up 24 x2 in the front and 28 x3 on the rear.
so basically i need a estimation of how long in need the spokes to be, i know this setup will be a bit heavyer but my spokes keep loosning up often with the rough roads here, i hear a build like this will hold up better and transfer more power in the rear.
also i was wondering if i should go with brass nipples, i hear they hold better and dont round out like aluminum ones will. though they are .3g or so heavyer per. i like to keep weight down but if somethings really worth the extra ill justify it.

thanks alot in advance, the community here has helped me through quite a few problems.

any other suggestions or advice is welcomed, im not to experienced with wheels.

Al1943

I use DT Swiss aluminum alloy nipples on all of my wheel with no problems. Some of these wheels are more than 12 years old. One wheel was rebuilt due to a broken hub and I reused the old spokes and nipples.
Whatever you decide to use I recommend that you use a good fitting nipple wrench that holds all four corners of the nipples.

Andrew R Stewart 

I don't think you'll find the changes to be measureably stiffer then the OEM wheel set. In fact one could claim with more spoke crossings (and the longer spokes needed) the wheels might be actually softer. Not that it's a bad thing to have some give in one's wheels. I would check the rim's condition before I'd reuse them. Spoke loosening can often be caused by a rim which won't let the spokes (on the same side) be of nearly the same tension AND still have the rim be true. So a rim with a bend (think potato chip)will have some spokes really tight trying to pull that portion of the rim straight yet have others loose because the rim naturally bends in that direction. I also suggest using brass nips. they will have less friction within the spoke holes of the rim (non eyeleted rims are worse in this aspect) allowing higher tension with less chance of rounding off a nipple. They are also stronger and suffer less long term corrosion. I would never recommend Alu nips for any one who has had previous wheel issues. Do consider using butted spokes. their slight bit more stretch will let you tension up the wheel easier and likely higher. Andy.

hueyhoolihan

i agree, that it's unlikely that you will notice much difference, but it's possible.

anyway, aluminum nipples are all that i use, but if you're looking for more strength and reliability there's nothing wrong, except a few grams, with brass ones. if you are changing # of crosses you will need to know, measure or research the ERD of the rim you plan on using and the hub flange diameters, both left and right and flange offsets, left and right, in order to calc the length of the spokes. but i suppose you know that.

FBinNY 

If anything, lengthening the spokes will make wheels LESS stiff rather than more. That's because 1- the spoke length is longer and 2- because the bracing angle is reduced.

The difference is slight either way, but whatever small difference it makes will be the wrong way.

Also, replacing the radial with a crossed and over/under laced pairs will also LESSEN stiffness because it introduces a certain amount of tension transfer.


Discounting very small changes the ONLY way to increase stiffness of a wheel is to use more steel. Either more spokes or thicker spokes or both.

Mopar440ci

ok thanks for the info, i may keep the oem setup then and just replace the components to suit. the rims and all that look good and dont have many miles on them, maybe 3-4k over the past 2 years. but i plan on tearing it all down to see for sure and to measure befor ordering anything.

FBinNY 

OK now that we've cleared up the stiffness issue, let's consider why your wheels are getting loose. Here are some possibilities

1- the wheels aren't suited to your weight -- may apply if you're near 200#s or more
2- the rims aren't stiff enough for this build. The longer span between spokes need rims that are more rigid so they cannot d=flex to where spokes are slack.
3- the spokes are too stiff for the application. This is counter-intuitive, but thinner spokes are stretched more at any given tension. More spoke stretch allows greater rim deflection before the spoke gets slack. So. perversely, weaker spokes can build a stronger wheel.
4- wheels simply not tight enough. The greater deflections of low spoke rims call for higher spoke tension. The same logic as before, you need the spokes stretched moore so they can never be slack when the rim moves.
5- lack or traction, nipple to rim, or nipple to spoke. Nipples are kept from turning by spoke tension. With deflections the spoke tension can drop to near zero, allowing them to move (they never tighten). So you want some back up traction to keep them from moving. Every builder has his own preference, but some kind of traction aid can make a world of difference.

That's a short list, and should give you ideas about how to improve the wheels and solve the loosening problem.

Getting back to your original question, while increasing crosses won't make the wheel stiffer, it can improve (slightly) things relating to your loosening problem. The difference is caused by the increase in flex longer spokes allow, but realistically, the difference will be very small.

Mopar440ci

thanks i belive it did help me, you see whenever i tighten my spokes, true wheel ect i have noticed that most of the spokes are as tight as they can go ( no more threads ) ive long thought that maybe the spokes were a mm or 2 too long for the rims build. dosent seem likely considering this is the stock rim for the bike and should be built to spec but it sounds likely based on what you say.

what do you think?

FBinNY 

Sounds possible. Usually makers err short, but the opposite is possible. This is more likely if the tops of the spokes are higher than the nipple head by 1-2mm. Next time you need to work on these, pull out a single spoke and thread on the nipple to see exactly how far it can go. Compare to the rest of the spokes and you'll either confirm or eliminate this theory.

Mopar440ci

ok ill be sure to try it, it will be soon because i got one or 2 loosening up on me again.
but this problem may also be with the spoke nuts, not long after i bought my bike i had some issue with one of my spokes. the nut loosened up and fell off and inside of the wheel on a ride, i took it to the lbs i bought it from because this shocked me and they fixed it good and tight only for it to be loose again after the next ride (same spoke, we marked it after the first time).
that is apart of the reason i want to go with all new spokes and nuts.

FBinNY 

IMO, this situation would have me questioning the LBS before I suspected the spokes and nipples. Possibly whoever is working on this doesn't get how high the tension has to be on wheels of this type.

I'd ask around about a shop with a proven wheel building reputation, and have them properly re-tension and true these to a reasonable spec. Failing that, rebuild with 14g double butted spokes, and tension them to something upward of 120kg. Use a thick grease or an oil that becomes sticky with time to minimize spoke twist at that tension (unresolved spoke twist causes the spokes to untwist and loosen when you ride), and/or a tacking agent between the nipple and rim.