Author Topic: Things to check on someone else's build  (Read 1162 times)

Things to check on someone else's build
« on: 14 April, 2018, 04:09:53 pm »
So this week I decided to cycle my 12km commute on the outskirts of Paris - amazingly 95% on paved forest track or dedicated cycle path with only a few hundred metres that's a little bit rough.

Ideal for the Kona hybrid bought from H*fraud on cycle scheme in 2008 and only briefly used by my son, maybe 200km max.

Anyway, it needed a longer stem.  When fitted I tried rocking the front wheel with the hydraulic disk brake on to check the headset tension - there was distinct movement. 

The headset tension really felt right, and on a closer look the disc brake bolts were at best finger tight and three were at least a half turn loose.

Googling seems to say that Shimano recommends 2-4nM.

It looks like someone tried to tighten the t25 bolts with an Allen key  :-)

My commute to work has a 2.5km descent at 4%.  Glad I didn't meet any of the local sanglier (boar).

Re: Things to check on someone else's build
« Reply #1 on: 14 April, 2018, 07:20:38 pm »
Did you take the bike back for its one-month checkup?

FWIW not that the pdi and setup is any good in a lot of chains, but finding loose bolts is not at all unusual on bikes that have been ridden only a short way. Most decent bike shops stress very clearly that you the customer are to bring the bike back after about a month of daily use to be checked over for exactly that kind of fault. Not everyone does, and simple problem can turn into a very expensive repair down the line.

Of course it is possible that the bolts were never tightened properly in the first place but it is also the case that many bolts are routinely used to tighten against painted surfaces; over time the paint oozes out of the joint and the fastener needs to be retightened. The one month check is meant to catch that kind of trouble no matter what the source.

cheers

Kim

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Re: Things to check on someone else's build
« Reply #2 on: 14 April, 2018, 07:45:54 pm »
Did you take the bike back for its one-month checkup?

FWIW not that the pdi and setup is any good in a lot of chains, but finding loose bolts is not at all unusual on bikes that have been ridden only a short way.

Quite.  Even when it's your own trusted work, it's prudent to do a shakedown ride or two and then check that everything's still tight.  If you've got new gear cables, these usually serve as a helpful reminder[1] by needing adjustment as they bed in.


[1] I gave my friend's shiny new e-bike a checkover after a couple of months and realised that this hadn't happened because between the hydraulic brakes and electronic gears, there weren't any cables to adjust.  Fortunately the only thing that needed attention was a slightly-rubbing mudguard.

Re: Things to check on someone else's build
« Reply #3 on: 14 April, 2018, 09:03:09 pm »
The bike wasn't used much so I probably skipped the one month check.

The bolts on the rear wheel were fine but the rear wheel is a low-end shimano hub (M475) and the front is a cost saving "formula disc".  The bolts tighten onto stainless rotors in both cases.

Live and learn is the lesson, I think.

Re: Things to check on someone else's build
« Reply #4 on: 15 April, 2018, 12:05:56 am »
When I saw the thread title I was about to suggest the brakes:)