Join Date: Dec 2007
Location: San Jose, California
Bikes: 2001 Tommasini Sintesi w/ Campagnolo Daytona 10 Speed
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Okay, I'm looking at that rear wheel and I personally don't like what I see.
That lacing used - is what many would call machine built lacing.
Normally when I custom build a wheel - I'll lace one of two ways...
1. ALL pulling/trailing spokes heads in.
2. ALL pulling/trailing spokes heads out.
One or the other, not a mix of both.
Right now you have heads in - elbows out pulling/trailing on the non-drive side and heads out - elbows in pulling/trailing on the drive side. When a sudden application of torque is applied, that can result in those spokes pulling the rim 1-2mm toward the left brake pad. The other spokes are going slightly slack and letting the rim "go" a little so to speak. It can get worse if your spokes have lost some of their tension over time.
Currently you have your rear at 2X, not 1X as you stated. So your crossing is fine.
As to tension - your low spoke count forces higher tension - regardless of whether the rim can handle it or not. You'll need your front 20 hole wheel tension up into the high 100's or even slightly above 110 in terms of kgf. The risk caveat though is you are going radial - you run the risk of tearing the flange. See below regarding Spoke Prep...
The rear drive side will need to be up in the 120-130 kgf range. That's what I typically find with pre-built 24 hole wheels from proprietary sources - Park has a chart that shows that tendency as well.
Some members here will suggest Spoke Prep on the threads as well....
Bottom line though is consider re-lacing the rear so that ALL pulling spokes are either ALL heads in or ALL heads out. And have your LBS wheel builder finish off with a tension meter just to be sure you're in the ballpark tension wise.
Once again, careful with the front...
ps. Some flex is frame related, nothing I can suggest for that...
4000+ wheels built since 1984...
1. I do not claim to be an expert in bicycle mechanics despite my experience.
2. I like anyone will comment in other areas.
3. I do not own the preexisting concepts of DISH and ERD.
4. I will provide information as I always have to others that I believe will help them protect themselves from unscrupulous mechanics.
5. My all time favorite book is:
Kahane, Howard. Logic and Contemporary Rhetoric: The Use of Reason in Everyday Life
Last edited by mrrabbit; 09-19-12 at 08:18 PM.