I have a big race coming up and I really don’t want to get a mechanical problem, which has pretty much been the theme of my season so far. Is there any way of showing if a shifter will suddenly fail on me mid race? Which has happened to me before… Or any way of predicting rear mech failure. Neither have been replaced at all since I got the bike in May 13 so I have a feeling it might be getting towards the end of their life. I just don’t want it to happen during my next race.
Cheers.

replace them all is the only way to be sure, you will have to at some point anyway but when it happens in the future you’ll have have used spares.

It will happen when you least expect it to, and when you least need it to. Such is the way of the Laws of Sod.

Both times a mech’s gone on me has been late on in a race: 4am at Sleepless and 85km into a 100km MTB-O event. Both times were pretty much user error combined with environmental factors (mud and bits of tree) as well, so not so much ‘component failure’ as ‘somewhat exceeded design spec limitations’. I’ve never had a shifter fail, but a freewheel went on the first climb of another MTB-O event. I don’t think there’s any way of second guessing it, unless you inspect vigorously for fatigue marks and check the internals of your shifters after every ride.

If you’ve only had the bike 18 months, unless you’re putting massive mileage on it, you shouldn’t be having bits ‘fail’ left right and centre.

Classic bathtub curve
Don’t run anything new or very old for important races

Check out the ”Bathtub Curve” for failures. You don’t want to be changing them just before a race – or letting them get to old they’re worn out.

Unless you’ve got time for a few good rides, leave well alone for the next race unless there’s a good reason to change.

Edit – as put more succinctly above ^^

my singlespeed has never broken a mech.

never won a race though; although i did come 4th at SSUK once 😉

Should be fine if thier new from 2013. You can off set failure by good regular maintenance. Before huge race such as Trans Portugal I have new cassette, chain and rings plus cables. Put them on a few weeks before and bed them in. I make sure my chain is well oiled. I carry small amount of oil and re oil the chain mid way. Takes only a few seconds. New tyres as well such as Maxxis. Weight savers such as nobby nics etc aren’t durable enough IMHO. I found mechs and shifters last me about three years. Hubs and BBs are checked regularly and serviced. Add good cadence and early shifts so your not over stressing the mech you should get through without any problems.

It’s an investment but I normally aim to wear out what I got to coincide with the race as part of the pre race prep plan. Yes I think about and plan it months ahead. All in all it’s just good regular maintenance.

replace them all is the only way to be sure, you will have to at some point anyway but when it happens in the future you’ll have have used spares.

Yeah good point.

Both times a mech’s gone on me has been late on in a race: 4am at Sleepless and 85km into a 100km MTB-O event.

I broke a shifter at about 2am in Bonty 24!

If you’ve only had the bike 18 months, unless you’re putting massive mileage on it, you shouldn’t be having bits ‘fail’ left right and centre.

Well so far its done Iron Bike, one 24 solo and a two 100km marathons and a few shorter ones, along with lots of other long weekend rides.

Hadn’t heard of the bathtub curve. Shifters and mechs don’t have to be bedded in though do they?

No but teething issues with set up probably better manifested on a training than race dayday.

michaelmcc – Member
Hadn’t heard of the bathtub curve. Shifters and mechs don’t have to be bedded in though do they?

No but the out the box faults (weak part, manufacturing tolerance etc) will come out in the first couple of uses in anger and the bad set up issues which lead to your mech being eaten by the wheel.
Then things run until the wear out or in mountain biking an unexpected event/rock hits them.

Give the bike a good once over, check for play in the mechs and shifts that feel worn out, check the cables are good and that everything is running smooth look for damage and wear, check your jockey wheels and chain wear. Apart from that you might be overthinking things a bit.