Is it harmful to shift RD while climbing standing?

Question

I'm just learning to climb standing, and I find I'm often guessing wrong about which gear to use; plus there are times where I'm accelerating up the hill and just need to shift up. Upshifts under power usually cause a loud clunk, so I sometimes "rotate easy" through the shift, but I'm not always that patient or adept.

My question is:

• Are full-power rear upshifts while climbing standing BAD for components, or is that a typical expected usage?

I'm still on my "learners" bike, an older MTB triple, and for now I'm still a heavy rider - 230 lbs. I'm actually not too worried about hurting this current bike, but would really like to avoid ingraining bad habits that I'll regret on an eventual new road bike.

I assume I'm putting a more stress on chain and derailleur - the shifts sure clunk pretty loudly. So far, no actual shifting problems. Is it just a matter of keeping an eye on chain stretch, or is this a practice I should minimize? (It's sure fun to accelerate up a hill though!)

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Postscript (6/25/2011): Hmm, look what happened to my rear wheel today. I'm not saying this is due to standing upshifts, or even just climbing standing in general. And it is a 20-year old MTB I bought used 2 years ago, so history is unknown. But hmm. I think I'll spin more and stand less :-)

Answer 1

Will you damage components?

Probably, if this is a repeated pattern, yes.

When standing to climb you will be in a higher gear than when seated climbing. This means the cadence of your legs and pedals is slower. Add to the slower cadence the fact that you are powering down hard to accelerate uphill and there is significant power going through the chain and derailleur over a chain moving too slowly. If you are hearing loud clunks, that is unlikely to be good for your bike's components. It may not result in immediate failure, but is increasing wear and could result in failure later on. Rather than chain stretch, you may get a link failure and chain snapping, or you may damage parts of the derailleur if you do this regularly under high power.

An alternative approach to changing gear while standing

Once you have got the bike moving at a speed where you feel the cadence is too quick standing, try going back to a seated position. It will probably now feel too slow to change up. This will also allow you to use different muscles. If you can still accelerate up to a speed where the cadence is too fast and you want to change up, then do so with the pedals spinning quickly but with a moment where you apply slightly less power.

General advice on hill climbing

As you change up, move to standing to maintain momentum and to account for the lower cadence of the higher gear. If you can still accelerate in the higher gear - repeat.

You may also find this article on How to Climb a Hill on a Bicycle a useful reference. Although he concentrates on maintaining momentum and the theory of when to attack to optimise energy efficiency through the hills rather than how to change gears..

Answer 2

Personally I changed my riding out of the saddle habits when I bought a speedometer. Rarely did I notice an increase in speed when out of the saddle, typically getting a 1 - 1.5 mph drop even if I felt I was going faster. Dancing on the pedals clearly has its place on very steep hills and competitive situations, but, for general riding, for me, staying seated and using the gears is more efficient.

There seems to be a misconception here about the 'strain placed on the rear derailleur'. Let's be clear that no matter how strong you are or how weak you are, or how heavy you are, or how light you are, any extra force applied to the pedals will not make a big difference to the mechanical lifetime of the rear derailleur.

The reason for this is that only the top part of the drive-train is under tension. The first few teeth at the top of the chainring and the first few teeth at the top of the sprocket do all the work, where the chain wraps around at the bottom is not under tension - the derailleur cage spring provides what tension there is and that does not increase just because you are going-for-it.

The rear derailleur feeds the chain in at the bottom in the low-tension part of the loop, the front derailleur does not - it acts on where the chain is tight (when pedalling), hence you definitely have to ease up when shifting chainrings.

As for the chain and sprockets that is a different matter. When changing gear there will be a point when those first few teeth are actually on two different sprockets. Because the sprockets are of different size the chain will not have a smooth transition from one sprocket to the next and the shift of the load from one to the other may not be exactly smooth.

With modern 'hyperglide' gears setup correctly the shift will be possible under load without too much scary goings-on. However this will result in mechanical wear. This wear will primarily be to the bushings of the chain resulting in what we call 'stretch'. In turn this 'stretch' will degrade the ability of the chain to spread the load over 'the first few teeth' of the sprockets (and chainset). The 'first few teeth' eventually becomes the 'first couple of teeth', then, with the load not spread the sprockets begin to wear, potentially resulting in a hooked shape that means only a 'stretched' chain will work with the gears.

Notionally chains have a life of 1000 miles, 2000 for a posh one. I advise that you ride as you feel fit, keep the gears adjusted to work and replace the chain every 2000 miles to avoid damage to the sprockets and chainring. You can ride the gears into the ground, putting 10K miles on a chain but this means you end up with a bill for replacement parts that comes to a lot more than it would have cost to replace the chain as per its service instructions.

Answer 3

Looks like you have other problems, i.e. spoke tension on your wheels is out of wack. Yes, you can shift while standing. Sprinters do it all the time, tandem riders to it all the time. You can do it all the time, you just need to maintain your bike properly.