First steep climb threw the rear wheel out of true. Seen this before?

Globalti

Legendary Member
The new Roubaix, which I'm loving, has DT Swiss R470db rims. Today I tried the bike out on the climb of Whalley Nab, our local little test-piece. Cleaning the bike later I spotted that the rear wheel had gone about 5mm out of true with high spots in two places. 5 minutes on the trueing jig sorted it down to an acceptable 1mm or less but I'm surprised it happened and can only assume it's due to the wheel "settling" under the stress of the climb.

I don't think the wheels are particularly good though. Has anybody else experienced this with a new wheel and can I expect it to keep happening until the wheel settles down? It's only done 190 miles so far.
 

Ming the Merciless

Formerly YukonBoy
Location
Inside my skull
Uneven tension or spokes unwinding under the high torque applied when climbing?
 

Ian H

I am an ancient randonneur, & I stop often for tea
Location
East Devon
It must be badly built, but should be recoverable as it's nearly new. How many spokes?
 

I like Skol

I don't think so, sonny!....
Location
Room 237
You are obviously superhumanly powerful and normal wheels cannot withstand your amazing output.... or maybe it is just a shite wheel. TBH, assuming it isn't a cheap bike (I haven't googled the price), I wouldn't have DIY'd it and would have just fired it back at the supplier with an instruction to sort it out appropriately.
 
Location
Loch side.
It wasn't uneven spoke tension, since that has nothing to do with wheel true. After all, a true wheel cannot have even tension and when the tension in all the spokes is the same, the wheel cannot be true.

Spoke unwinding makes a very clear pinging sound but under the conditions you describe, only happens to the pushing spokes, not the pulling spokes.

I think the wheel wasn't properly stress-relieved and the spokes where not de-tensioned after the build, so all any wind-up to disappear.

Overall, a poor wheel build.

To remove spoke windup, follow the advice in this link.

https://www.cyclechat.net/threads/broken-spokes-on-turbo-bike.253762/#post-5759874
 

SkipdiverJohn

Veteran
Location
London
I bet it has a lot less than 32 or 36 spokes in it! I've never put a wheel that far out of true by just riding it, only by kerb-hopping or crashing over big potholes.
 
I’ve only encountered something like this when I haven’t ensured the spokes were correctly tensioned on new wheels, then climbed, out of the saddle, and the bike was rocking from side to side. I always check the spoke tension on new wheels before I ride now.
 

PpPete

Guru
Location
Chandler's Ford
Not seen it happen under extreme load from climbing before, but have seen a previously "true" wheel from an entry-level Spesh Allez just pringle (taco) from a very minor impact. Initial investigation at roadside showed massively uneven spoke tensions were needed to stop brake rub on the rim even with quick release wide open. A complete rebuild (or rather strip down prior to attempted rebuild) showed that the rim had a substantial natural bow. How it had ever got beyond a basic QC step at Specialized (or their subcontractor) is beyond me.
Surprised and disappointed that similar should occur on a Tarmac.
 

si_c

Veteran
Location
Wirral
Those rims are pretty bomb proof in my experience- I have essentially the same rims on my commuter wheelset. Last time I had to true the wheel was when I had a high speed interfacing with a BTopenreach engineer - the rim is actually quite a bit pringled but has stayed within 1mm since I trued it up.

Might be worth spending a little bit of time to build them up properly.
 

si_c

Veteran
Location
Wirral
They may be bomb-proof but if the rims are not straight before they get laced they are fubar.
No amount of "building them up properly" will help.
I know, my point was regarding his wheel, will be worth rebuilding the wheels in the case that the wheel was built poorly. I know my front wheel is shagged, I've got a replacement rim ready to go on, but I'm fundamentally lazy.
 
OP
Globalti

Globalti

Legendary Member
I have my concerns about the wheels after spotting a mysterious dent in one rim, no paint damage but just a small dent made by something blunt, so it seems a little fragile..

Now that I've trued the wheel laterally it has got a small amount of radial movement so I'm going to need to remove the tyre and sit down properly with the spoke key when I've got no distractions. Maybe this evening when I'm home alone. I should take it back to the dealer but that's a 60 mile drive and TBH they handed me the bike in such poor adjustment that I wouldn't trust them to get it right.
 
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