Can anyone true Campagnolo G3?

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Valbrona
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by Valbrona

I've never trued up a wheel with Campagnolo G3 lacing. But is truing a G3 wheel vastly more difficult than truing a regular wheel?

Thanks.

by Weenie


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petal666
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by petal666

Not vastly, but it is harder to get it totally straight (and round)

Valbrona
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by Valbrona

Puzzles me a little why Campagnolo Techs get special G3 training so they can call themselves a 'G3 ProShop'. Answered my own question there ...

Permon
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by Permon

I have never met anybody who would need trueing Campa wheel.....so, why bother about trueing it? :D :twisted:

Seriously, I have been running Neutrons, Hyperons and Boras for many years....never touched a spoke and I am in 85-95kg range.

graeme_f_k
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by graeme_f_k

Campag techs get specific G3 training as the build and true process is not like a conventional wheel.

If you try and build a G3 by conventional means, you are potentially in for some surprises as the rim, in the raw, is not round to start with. This straightaway throws many wheelbuilders.

Additionally, offset has to be correctly introduced into the rear wheel - the gear-side nipples on Shamal and Eurus, particularly, are right on the margin of the ability to transmit torque without rounding in the finished wheel and this has some implications for how the offset is acheived on the rear wheel.

We also make recommendations about how many times a spoke key should be used for a full build before replacement and which way round the key should be used in tightening and loosening operations to prevent the key from spreading prematurely - since a good many mechanics haven't been told that even common-or-garden offset-jaw combination spanners, cone spanners and the like have a right and a wrong way round to be used, this comes as a revelation to many ...

The paired spokes on the gear side need to be treated as one spoke (i.e. the tension in both should stay as close as possible to exactly the same) until the very final stages of truing and the net amount of tension in each group has also to stay the same otherwise the danger is that if it reduces in a group, the rim will "bulge" at that group (this can be corrected) or if the tension is increased, the rim will bulge between the spoke groups. In the latter case, if this goes too far, it can't be corrected.

In some ways it's easier to learn G3 truing if you have never built a wheel as you come to it with no preconceptions - on the other hand, a passing familiarity with "how it's done", and concepts around spoke tension, offset, etc are also useful.

In response to the OP, I'd say - if your wheel is in warranty, send it back to us as the main UK SC or you will void your warranty. If it's not in warranty, the job can be done either by you as an end-user or by (preferably) a Pro Shop who have had the training but it does require care and attention.

If you go down the latter route, bear in mind that the shop may need telling (if they haven't done the course) that the nipples are loctited post-build (they are most likely not, as we are so often told by shops "seized" ...) and that the shaft of the spoke needs to be held with an appropriate holder right up next to the point where the spoke goes from aero to round - hold it further out than that and you risk a "candy-twist" or breakage (same net result anyway - the spoke will need replacing).

HTH
Graeme
A Tech-Reps work is never done ...
Head Tech, Campagnolo main UK ASC
Pls contact via velotechcycling"at"aim"dot"com, not PM, for a quicker answer. Thanks!

graeme_f_k
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by graeme_f_k

Valbrona wrote:Puzzles me a little why Campagnolo Techs get special G3 training so they can call themselves a 'G3 ProShop'. Answered my own question there ...


Oh, so cynical ....
Learn something about the subject, then you will know ...
A Tech-Reps work is never done ...
Head Tech, Campagnolo main UK ASC
Pls contact via velotechcycling"at"aim"dot"com, not PM, for a quicker answer. Thanks!

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Calnago
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by Calnago

Hi @graeme_f_k: you described this in another thread once and I found the part about the "bulges" between groups of spokes in an untensioned g3 shamal rim very interesting. I asked the following question in that thread but it went unanswered. I'll ask it again here. Are the slightly non round sections that are present in Shamals, and I presume other alloy g3 wheels, also present in the carbon G3 versions like the Bora Ultra Two? Seems carbon would have less "give".
I have only ever had to true one Bora Ultra Two as a result of breaking a single spoke. There was no riding it after the break of course, the price we pay for high tensioned low spoke wheels. However, I just replaced the broken spoke and nipple with one from the appropriate Campy Bora spoke kit and all has been good ever since. And as a testament to these wheels strength I once nailed a huge pothole unweighted from the saddle as I didn't see it coming and the riders in front failed to call it out in time. The thud was so big I was sure it must have broken. But to my surprise I got away with no damage other than a double pinch flat.
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Permon
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by Permon

Calnago wrote:Are the slightly non round sections that are present in Shamals, and I presume other alloy g3 wheels, also present in the carbon G3 versions like the Bora Ultra Two? Seems carbon would have less "give".


I noticed my Boras 35s are not perfectly round when there is no weight (rider) on the bike. I quess when there comes a weight on the saddle, the rim comes to round shape (?), because I do not feel any bumping while riding.

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Calnago
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by Calnago

No, I'm talking about an untensioned rim. When it's all tensioned up it should be round, at least as far as I know. I've found the wheels from Campy to be very round and true from the factory.
Colnago C64 - The Naked Build; Colnago C60 - PR99; Trek Koppenberg - Where Emonda and Domane Meet;
Unlinked Builds (searchable): Colnago C59 - 5 Years Later; Trek Emonda SL Campagnolo SR; Special Colnago EPQ

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rmerka
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by rmerka

Permon wrote:I have never met anybody who would need trueing Campa wheel.....so, why bother about trueing it? :D :twisted:


Permon wrote:I noticed my Boras 35s are not perfectly round when there is no weight (rider) on the bike. I quess when there comes a weight on the saddle, the rim comes to round shape (?), because I do not feel any bumping while riding.


Sounds like you just met one :thumbup:

martinko
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by martinko

Permon wrote:I have never met anybody who would need trueing Campa wheel.....so, why bother about trueing it? :D :twisted: .


And what if you crashed the wheel so it became untrue? Would you trash it or true it? I ride Fulcrum wheels and they are really bombproof, but after crashing them, they needed to be trued.

Permon
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by Permon

martinko wrote:
Permon wrote:I have never met anybody who would need trueing Campa wheel.....so, why bother about trueing it? :D :twisted: .


And what if you crashed the wheel so it became untrue? Would you trash it or true it? I ride Fulcrum wheels and they are really bombproof, but after crashing them, they needed to be trued.


:D I believe You saw the emoticons in my posts....it was a joke :wink:

Permon
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by Permon

rmerka wrote:
Permon wrote:I have never met anybody who would need trueing Campa wheel.....so, why bother about trueing it? :D :twisted:


Permon wrote:I noticed my Boras 35s are not perfectly round when there is no weight (rider) on the bike. I quess when there comes a weight on the saddle, the rim comes to round shape (?), because I do not feel any bumping while riding.


Sounds like you just met one :thumbup:


I do not think so....I do not feel any bumping while riding. Maybe You could read the post before You reply :wink:

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rmerka
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by rmerka

I'm pretty sure I read: "I noticed my Boras 35s are not perfectly round when there is no weight (rider) on the bike." If you wheels are not perfectly round when they are unweighted then they are NOT true. Just because they say Campagnolo doesn't mean they defy the laws of physics :roll:

r_mutt
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by r_mutt

graeme_f_k


is this candy-twist what you are referring to?

I had a mechanic true my Shamal wheels and although i never checked when i received them back, a month later, i noticed that 5 rear spokes were twisted. Is this something my mechanic did wrong? I can't imagine that the wheels did this by themselves. i took them back to him and he claims that he's seen this before and it's fairly common that these have seized.


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by Weenie


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