krobinson103

My Brevet bike broke two spokes at the same time a few days back. replaced them and trued the wheel as best I could (I'm no expert so I can't get it absolutely true, but it turns). Had some issues with the caliper and an untrue wheel so for now I dropped in a wider single pivot caliper. Wheel tension seems to be even but the rim won't come true and when I do true it the spokes are too loose. I have a 200lm brevet in two weeks and not enough cash to replace the wheel until next month. Is a repaired, stable, but slightly untrue wheel likely to break more spokes? The single pivot caliper is ugly but it works and I can live with it till I find a nicer wheel set.

Retro Grouch 

If it's too wobbly I'd vote for that over loose spokes on one side. If you try to tighten the spokes too much on the other side they will eventually pull through the rim.

Good luck!

krobinson103

Commuted on it. No worse than the beaters downatairs, but they don't go 260km in one hit. Broken spojes.means.a DNF or a rear brakeless ride on a questionable wheel.

JohnDThompson 

Breaking two spokes at once suggests that it may be time for a full rebuild. If you can't do this before your brevet, be sure to carry extra spokes and tools to fix your wheel on the road.

davidad

I usually loosen all the spokes and retrue the wheel when I have your problem.

SBinNYC

There are too many unknowns to make any judgment regarding your wheel's ability to go the distance without further damage. If you are confident it can last 200K then go for it.

The problem with a wobble that clears the frame is braking. You have compensated for this by substituting a single pivot brake. You will be able to stop.

Just the same, I'd carry extra spokes (of the correct size), a spoke wrench and what you need to remove the cluster - if it's a rear wheel. Stuff the spokes inside the handlebar and forget about them until needed. If it's the rear wheel, separate the spokes by size and place them on both sides of the handlebar.

Unless brevet rules have changed, riders cannot receive any support between controls. That used to mean the rider was responsible for getting his bike to the control.

I had a similar situation the first time I completed PBP. I popped a spoke while training in Vermont. I did not want to do the brevet on an untested wheel so I did not rebuild before going to France. I popped a second spoke in France while training before PBP. I still preferred the devil I knew to one I did not.

However, I purchased a box of spokes and carried them with me. I knew spokes would keep popping - but I did not know when. I would rebuild the wheel, if they started popping on the brevet. I can build a good enough wheel on a frame within an hour. My PBP plan had me making the controls by at least two hours. I was lucky. I had no wheel problems during the 1200 k.

hueyhoolihan

i've had reason recently to test my skills at truing a wheel with a missing spoke. turns out it's pretty easy. couldn't really see any wobbling after altering the tension on a few other ones. a thirty-six spoke wheel produced a better result than 32 spoke wheel, IME.

fietsbob

Im blind over here.. I suppose the broken spokes let the rim be mechanically bent. the metal stretched on one side and compressed on the other .

with forces of just replacing the spokes , and loosening some and tightening others pulling it back towards flat, being insufficient to un do the mechanical bending..

may be unable to make it right without replacing the rim with one that is flat in one plane and Round .


In the mean time whack on the wheel to try to get it less bent , first, Caveman banging. .. then try to use the spoke tensions ..

krobinson103

Spent two hours last night using the caliiper dialed in as close as possible as.a feeler. Doesn't in perfect pitch but it is within 1mm of true and clears a dual pivot with space left. Sheldon Browns' wisdom helped, but I still think the rim
needs to be convinced into trueness. Think I'll go get a Shimano R series rear wheel as soon as I can.

chriskmurray

I would ride it if you really do not want to miss the brevet but also bring along a fiberfix spoke if you have one, if not often times you can loosen the spokes next to the broken one and still ride the wheel for a short while should you break another spoke on the brevet.

I would get the wheel rebuilt or replaced as soon as finances allow though.

krobinson103

Brake track is showing signs of wear anyway. Rim is about gakf worn out. Gets tidden up and down hills a lot. Didn't realize rim brakes wore so quickly. My other long distance bike runs discs and has gone three times as far wuth zero problems.

SBinNYC

The 1 mm isn't quite paper clearance (0.2 mm) but is plenty good. It's important to make sure the wheel will hold up. Make sure no spokes are really loose. Make sure you stressed the wheel.

If you are going to make a habit of riding brevets, I'd stay away from anything that uses non-standard spokes (everything other than standard J shaped spokes with the nipples at the rim). If there's any repair on the course, the chances are they will have only standard spokes.

krobinson103

My eyes aren't good enough to get much more and a brake is a limited tool as gauges go. Pretty good to a point then it does its job and stops the wheel making it hard to rotate it to see if its true.