I am re-lacing my hub with a new rim, spokes and nipples for the first time. I made a post earlier where I had some helpfull advice. Second time around with a slower approach and a few changes, i'm met with the same hop in the same place.
I wouldnt be in a rush to resolve it if I didnt need the wheel for a bike trip abroad next Thursday.
Im sure its my newbie skills causing the hop but im wondering if its just worth taking to a wheel builder to build the wheel properly/ check the rim doesnt have anything wrong with it, given I need a rear wheel fairly urgently.
Any advice welcome thanks
by LeadingNo6913
3 Comments
I guess you don’t have a tensiometer eh?
Generally the idea is to evenly tension each spoke to within x% of every other spoke. [Park Tool has a very helpful tool for this](https://www.parktool.com/en-int/wta). This helps prevent hops like that.
Given the need for a trip abroad, I would take it to a professional and see if they have time before next Thurs. The last thing you want is a wheel breaking in the middle of your trip.
I can’t tell, and did not see your last post. But rims are built in long tubes, cut, then welded or pinned together opposite the valve hole. If the hop is opposite the valve hole, you probably won’t be able to get rid of it completely. If not, you have to resolve it with spokes. So, always work in odd number spokes. If it hops up, loosen the 3 spokes centered around the hop. Loosen 2 spokes 1/2 turn, and the middle spoke 1 turn. 1/2+1/2 = 1 turn. That way, the side to side true stays the same. If the hop is longer than 3 spokes, use about the same math and work with 5 spokes. But always odd number of spokes.
Can you say exactly how big is the hop? It looks like a couple of millimeters, but I don’t fully trust what I see because I don’t know how stationary the tape measure is.
If it really is a couple of millimeters, then it’s really quite a lot and I would proceed as follows:
1. Loosen all spokes around the hop a full turn, and then check radial trueness again. If it’s still not true, then loose the same spokes again a full turn. Do this until you get the radial error closer to 0.5 mm.
2. Then go back to lateral trueness. Most likely your radial adjustments threw off the lateral trueness.
3. Then check the overall tension of the wheel — it’s probably now too low because you loosened a lot of spokes in step 1. Increase the tension on all spokes so that you get back to the rim’s spec. This is a good time to also check the dishing.
4. Then do final adjustments so that the wheel is true both laterally and radially.
And just to clarify, I say loosen spokes in step 1 because radial adjustments are significant. Because your overall tension is already quite high, you just cannot tighten a large number of spokes at this point.