Make your drive train moving parts last longer...

Chunkers1980

My mate has just got himself a 'proper mtb', was giving him some advice and it occured to me that not a lot of people seem to realise from what I notice....

Whenever you finish riding your geared bike of any discription you should leave it parked with the rear mech in the smallest cog on the rear (largest cog for rapid rise) as it will make your mech function better for longer as the spring will be in its least stretched position. Not so important on the front, as the spring is stronger and doesn't require the precision of the rear but will also help to leave it in the smallest cog....

Do others follow this practice? If not it's a very good idea to get in the habit....

ride_whenever

no, the spring only effects return, so as long as you keep the drivetrain clean you get smoother shifts with less spring tension. Soft springs are awesome.

Chunkers1980

That's your opinion about soft springs. I'd have thought the big Ss would know best.. So what you're saying is that they sell new mechs that are sub-optimum and build in tolerance to negate this, so it improves with time.... utter guff... I'm going to leave mine in the big cog in the front and back cos that'll make it function better.... what a load of tosh....

supersonic

Try and be more constructive rather than posting insulting comments, just because someone disagrees with your methods.

Given I have 13 year old XTR rear mech, and I usually keep it in one of the largest rear cogs,I can safely say it hasn't caused me any problems and the mech works fine.

Also many parts are built with bedding in in mind - maybe not in this case, but certaily happens ie tight fork seals and bushings, bearings etc.

bike-a-swan

i've been told to leave it in the 'small' gears since i got my first bike...

Rob-Is-On-Fire

The forces on these springs are not great enough even over a long period of time to create any significant deformation. In the past what you are suggesting was true and good practice, but spring quality has since improved, and manufactures are using better quality metals and more thoroughly researching correct spring size to avoid this problem.

Also you shouldn't cross your gears (big ring at the front and back) as this laterally stretches the chain.

Chunkers1980

I wasn't insulting ride_whenever, may have come across a little harsh though. I can just see with my own eyes that leaving your bike in first gear is going to do more 'damage' than it is good. I take the point that better quality metals that have a better 'memory' are used these days, still doesn't wash, what I said first still stands, the less tension on a spring the better.. Just trying to make people aware of what I've noticed, and the consequences of doing so.

supersonic

Fair enough lol. Just not something I have noticed.

ride_whenever

Not to mention to permanently deform the spring which I assume is steel/ti you need to take it past it's elastic limit. Which it simply wont do, otherwise your spokes would go slack if you left your wheels alone, which equally isn't the case.

Rob-Is-On-Fire

good example ride_whenever!

a metal must be pushed past whats called it's yield strength before it will deform from its original shape. The springs in a mech will not have a stress greater than their yield stress applied to them. The design just does not allow it.

Therefore in a perfect world the springs should last forever. What you need to look out for is corrosion as this will weaken the metal. But the most common type of failure in a metal is from fatigue. Fatuigue failure results from the stress within the metal frequently changing. It could be argued that by change gear at the end of each ride you are working the springs more so their performance is more likely to suffer from overuse.

Rob-Is-On-Fire

either way, i think the effect would be insignificate

supersonic

Most mechs die from the pivots going sloppy, or simply bent cages from impact.

Though I have seen springs feck up, though probably due to displacement or corrosion.

Mancunianfightingcat

best leave your car's engine with all the valves shut too, so you don't stretch the valve springs, oh yeah take the weight of the wheels too.......

I can see where you're coming from, but have you considered wha'ts happening to the lower cage spring or your chain if you leave your bike in different gears? I tend to leave mine about in the middle at both ends.

nicklouse

Mancunianfightingcat wrote:

best leave your car's engine with all the valves shut too, so you don't stretch the valve springs, oh yeah take the weight of the wheels too.......

not all of the above is possible without dismantling the engine.

Mancunianfightingcat

Really?

nicklouse

well I am not sure about the wheels

captainfly

If a spring is with it's range of tesion and compression it doesn;t make any difference to it's lifespan once a spring is set it's fine, over compression of extension will do damage. The only thing I can think of on a mech is releasion cable tension to make the cable last onger but I doubt it would be worth the effort.

stumpyjon

Seem to be a few of these 'myths' floating around at the moment. I usually leave my gears set so they are right for when I get on next time around. So far the only way I've killed a mech is to rip it off.

joshtp

stumpyjon wrote:

Seem to be a few of these 'myths' floating around at the moment. I usually leave my gears set so they are right for when I get on next time around. So far the only way I've killed a mech is to rip it off.

+1, iv killed a few mechs, but never from a slopy spring.

BorisSpencer

I usually click to a larger cog on the back just for the convenience of a lighter gear when restarting.
But if I get off the bike I then click the shifter a couple of times without moving. When I get back on the bike I just up shift again to take the slack back out of the cable. It's no inconvenience to me, but it means if someone else jumps on the bike they set off in a crash of gears and missed pedal strokes.

bails87

Thats what I do if I have to leave the bike unattended, but still in sight. Just so someone can't jump on and ride off.

Someone on the commuting/roadie forum told a tale about having his fixie (nearly) stolen. He nipped into a shop and left it outside, saw someone jump on it. Ran out and shouted "Oi" as the thief rode off, standing on the pedals. Thief heard the shout, looked round and stopped pedalling......only to be thrown off the bike by the fixed hub. The owner casually picked up his bike from on top of the bleeding lowlife and happily rode off.

craker

My personal experience is that this just isn't an issue. My MTB is ten yo, Deore XT I think and I'm a stickler for leaving my chainset in its easiest combination (dunno why, means I can start whatever and choose my gear rather than be struck on a hill).

I've changed jockey wheels and cables. Several chains. It still works fine and if it broke tomorrow I'd be happy enough.

Echo what others have said about exceeding elastic limits. If you design your mechanism so that you're deforming [edit - that's stretch it past its yield point] your spring when you tried using it it would last... once.

biff55

by the time the spring looses its strength , ie a long time , the jockey wheel teeth
will have worn anyway.
either way it gives us an excuse to buy shiney new bling parts
silver clouds and all that.