drivetrain voodoo. does your shifting do one thing on the stand, and something else

Discuss light weight issues concerning road bikes & parts.
wingguy
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Joined: Thu Mar 08, 2012 11:43 pm

by wingguy

ParisCarbon wrote:
Fri Apr 12, 2019 4:21 pm
Doubt it... 2 certified mechanics, rd dropout alignment, current firmware.. we were thinking somethng internal with the battery itself.. will never know, its EPSd now
Rear mech issue almost certainly just a too tight limit screw. Chain will drop when slack, but not under riding tension. Ghost shifting odd though.

mattr
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by mattr

ParisCarbon wrote:
Fri Apr 12, 2019 4:21 pm
Doubt it... 2 certified mechanics,
You any idea how easy it is to get "certified".
It's a bit like a driving licence, just shows you meet the absolute minimum standard necessary.

by Weenie


tarmackev
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Joined: Sat Jan 15, 2011 9:59 pm

by tarmackev

Working as a bike mechanic servicing and building bikes I never had ghost shifting but I’d say lots of bikes need an adjustment when riding on the road.
Generally just a twist of the barrel adjuster on the rear mech one way or another.


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Calnago
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by Calnago

tarmackev wrote:Working as a bike mechanic servicing and building bikes I never had ghost shifting but I’d say lots of bikes need an adjustment when riding on the road.
Generally just a twist of the barrel adjuster on the rear mech one way or another.


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Agreed, for sure a properly set up bike should work the same whether in the stand or on the road, but a weighted frame and rider on the road will uncover any possible slight improvements that can be made which may or may not have been detectable in the stand. That’s what test rides are for.
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

mattr
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by mattr

TBH, a lot of that is the outer cables settling into place. Made worse by them not being perfectly square. (or being cheap!)
FWIW i've just finished building a bike for a mate and had to recable the rear mech as i neglected to finish the ends properly. It wouldn't even shift consistently in the stand.
(Really should have said no to the build, i've got *far* too much else on my mind at the moment. Just couldn't be arsed to go and get the right tool for the job from the other workshop!)

Usually running through the gears (and brakes) with some resistance highlights issues like that.

mattr
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by mattr

Oh, and another thing i noticed on a Di2 build a few weeks ago which was problematic (missed shifts, random shifts) was a damaged connector into the junction box. Looked like it'd been fitted cockeyed with a pair of pliers.

I've seen no further cursing on FB since then, so i guess the problem has been rectified. Or it's been replaced. The bike i mean, guys got more money than sense.

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Calnago
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by Calnago

I always make sure the housing ends are perfectly square and take them to the grinder to ensure that, much better than dickin’ around with a file or something. But files work too, just takes longer, and if you’re working on a bike where they’re already installed it’s probably easier. All depends on how anal you wanna get with it all.
Also, re the settling in of new housings, I like to “pre settle” them. I’ll cut them to length, essentially run them from the shifters to their respective stops and pre bend them to the curvatures they would ultimately acquire naturally to get that settling out of the way from the start. All part of what makes a quality build a quality build.
But no matter the care I take during the build or in the stand, a test ride is always the final step.
Of course, with the electric stuff, it’s much easier and you just plug everything in. The only real fiddly thing with this stuff is routing and ensuring that there’s no loose wires inside causing any annoying rattles. Then taking the time to “zero in” the shifting properly. Broken junctions etc, well, there’s not much you can really do there except replace them. And yup, a final test ride to ensure everything is as it should be. Shifting under load is always a different experience than shifting in the stand, but the shifting should work fine under either scenario when dialed. Unless maybe you’ve got some complete noodle of a frame and/or some huge wattage heavier rider involved.
Last edited by Calnago on Sat Apr 13, 2019 6:51 pm, edited 1 time in total.
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

mattr
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by mattr

:D Have seen grinders melt the liner before now.
Decent flat file and a small vice/clamp works equally well. In seconds as well.
Dremel with a cutting disc is also quick and clean.

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Calnago
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by Calnago

Ha, they will totally melt the liner. I make a quick pass and have a cut off and sharpened 1.5mm spoke on hand which gets poked in and twisted with every pass so as to ensure the liner doesn’t get melted shut. Mostly use it for the brake housings.
I use a first gen 10sp Campy chaintool (straight plate vice grip for the “Permalink”) when I want to hold the end of a housing firmly while on the bike and use a file instead. Lol. Now I’m just giving away secrets for free.
Also have used the dremel with cutting disc. Not my preference and seems to have more chance of messing things up than either of the other methods.
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

ParisCarbon
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Location: Winnipeg Canada

by ParisCarbon

Meh its EPS'd now and life is much better :)

tarmackev
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by tarmackev

I’ve seen issues when people didn’t have the cable outers properly seated in the shifters.
I’ve seen shifter bodies slice in to the outer, it all feels solid but there’s a couple of MM movement. It’s often the last place people check as it involves removing bar tape.
If everything else looks good it’s the next go-to place.


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Calnago
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by Calnago

^Yup, these are all good points being made about setting up mechanical properly. EPS/Di2 is easier to set up properly for sure, but not without their own issues. But if you get a Campy mechanical system dialed, there is no faster shifting group available, from any combination to any other combination of gears. And it’s way more fun. Click!
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

Catagory6
Posts: 366
Joined: Thu Feb 09, 2017 2:36 am

by Catagory6

any thoughts? i did the tap test. no difference in sound. pressed down on the crack. no give. took it to the local shop and had a guy sit on the bike. no noticeable movement in the crack. guy said it might be a seam.

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