Small to small big to big

[lutonloony]

once again apologies for probable repeat posting (did try a search). I understand that running big front to big back ( or small to small) puts lots of lateral stress and can cause excessive wear, but my question is what would be the max recommended number of cogs to go up to if on big front? ( am on 105, 11 spd)

 

[uclown2002]

Personally, I try not go beyond the third largest.

 

[slowmotion]

I'm not a competitive cyclist by any stretch of the imagination. If you are a recreational rider, I really wouldn't worry about "cross-chaining" at all. My rule of thumb is that if the chain sounds OK, it's probably quite happy. If it chatters a bit, put it somewhere else where it sounds happier. I'm not a big believer in all that chain wear stuff.

 

[cosmicbike]

With 11 speed 105 you can 'trim' the front derailleur, so can cross chain big-big or small-small without the cage rubbing. That said, from what I understand it will increase wear on the chain and rings, so I tend to go 3 up - 3 down, avoiding the top 2 cogs whilst on the big ring, and vice versa on the small ring. Whether this makes any difference or not I don't know...

 

[SpokeyDokey]

Just use whatever gear feels right to you.

All components involved are cheap consumables.

I cross chain (big/big) almost every ride and my current set-up has around 3000 miles on it and everything works perfectly fine.

 

[cosmicbike]

I cross chain (big/big) almost every ride and my current set-up has around 3000 miles on it and everything works perfectly fine.

You mean you don't fit a new chain every 2000 miles? How does it survive

 

[SpokeyDokey]

You mean you don't fit a new chain every 2000 miles? How does it survive

Dunno! It's clearly defying internet forum fueled convention.

I rarely clean it either - gets a few drops of Teflon imbued wonder oil every few weeks and it seems to merrily chug on doing it's thing in its blackened grimy state.

 

[Justinslow]

I managed to crash my derailleur into my wheel coming up a hill under power practicing for a TT. Big front to biggest rear. Made quite a mess, broken hanger, broken deralier, bent chain, stretched cable, couple of bent spokes and buckled wheel, oh the shame.
Lesson learned, I always leave one cog spare now unless I'm really not under load then it's ok to use.

 

[Nibor]

I run a triple and tend to stay in the middle ring most of the time.

 

[MichaelW2]

I generally try to avoid crosschaining the outermost 2 rear cogs but I'm not religious about it.

 

[Bollo]

I thought about writing an Connect IQ app for by Garmin 520 to beep if you'd crossed the chain but the Garmin programming framework doesn't give access to the Di2 gear info.

 

[T.M.H.N.E.T]

SRAM Yaw derailleurs are designed to allow just this without rasp/rub. They can be fiddly to setup perfectly at first but it's a great system.

1x systems are also usable throughout the cassette range

 

[Ajax Bay]

avoiding the top 2 cogs whilst on the big ring, and vice versa on the small ring.

Is the correct answer and best practice.
Of course you can just ignore all this but why not cycle with good technique? For example, you can cycle with a low cadence all the time, but it's not good practice: it increases wear on one's knees and is harder work (so less efficient).
A chain works best if the front chainwheel and rear sprocket is directly in line. Cross chaining at the extreme results in an angle of 3 degrees (11 speed) and so the links under tension (ie along the top) are having to cope with this and in particular each link as it comes off the sprocket and again as it goes onto the chainwheel. This causes both wear and friction and thus reduced chain durability and efficiency. Try using this gear calculator and adjust the 'Chain angle' box which nicely illustrates the effect of keeping the angle down.

 

[gasinayr]

Have a look at some gear tables, you will find that some ratios, eg big / big will be the same on say middle front 3rd rear. Get to know you gearing to avoid crossing over. Get a chain wear gauge and test the chain ever month or so. If you leave the chain too long you will have to replace the chain, chainrings and rear cassette

 

[Justinslow]

Is the correct answer and best practice.
Of course you can just ignore all this but why not cycle with good technique? For example, you can cycle with a low cadence all the time, but it's not good practice: it increases wear on one's knees and is harder work (so less efficient).
A chain works best if the front chainwheel and rear sprocket is directly in line. Cross chaining at the extreme results in an angle of 3 degrees (11 speed) and so the links under tension (ie along the top) are having to cope with this and in particular each link as it comes off the sprocket and again as it goes onto the chainwheel. This causes both wear and friction and thus reduced chain durability and efficiency. Try using this gear calculator and adjust the 'Chain angle' box which will illustrate the effect of keeping the angle down.

So for an 11 speed you've only got 9? Seems a waste of a couple of gears for me!
I think you've just got to be sensible using them, don't do what I did and put massive power through cross chaining. If it's just trundling up to or away from a junction etc it's fine.