Would this be cross-chaining?

[sergen]

I've worked out the various gear ratios that come with the standard version of the 2006 Giant TCR 2 (which I've more or less now decided that I'm going to get)

Shimano Ultegra components 52/39/30 up front and 10 speed 12-25 cassette are the standard components coming with this bike.

My question concerns the possibility of damaging the teeth through potential cross chaining. Imagine cycling along in 52x16 - I believe this would give 88 gear inches. Now if I wanted to shift down into 52x17, (giving 83 gear inches) it would mean moving towards the 6th sprocket on the cassette (I don't know if it's actually called the 6th sprocket - I think of 12 as being the 1st sprocket, 13 the 2nd, etc. I may have got this the wrong way around in cycling parlance).

On a 10 speed cassette this would mean moving the chain onto the second-half of the cassette's range. Could one get away with doing this without any damage and loss of pedalling efficiency?

Many thanks

 

[boudreaux]

I've worked out the various gear ratios that come with the standard version of the 2006 Giant TCR 2 (which I've more or less now decided that I'm going to get)

Shimano Ultegra components 52/39/30 up front and 10 speed 12-25 cassette are the standard components coming with this bike.

My question concerns the possibility of damaging the teeth through potential cross chaining. Imagine cycling along in 52x16 - I believe this would give 88 gear inches. Now if I wanted to shift down into 52x17, (giving 83 gear inches) it would mean moving towards the 6th sprocket on the cassette (I don't know if it's actually called the 6th sprocket - I think of 12 as being the 1st sprocket, 13 the 2nd, etc. I may have got this the wrong way around in cycling parlance).

On a 10 speed cassette this would mean moving the chain onto the second-half of the cassette's range. Could one get away with doing this without any damage and loss of pedalling efficiency?

Many thanks

With a triple and 10 speed you can use all but the 2 biggest cogs when in the big ring. More conservative folks might say don't use the biggest 3

 

[artmichalek]

On a 10 speed cassette this would mean moving the chain onto the second-half of the cassette's range. Could one get away with doing this without any damage and loss of pedalling efficiency?

It all depends on what you mean by "use". Any gear combo will work in a pinch, but as boudreaux said, running the big ring with the three biggest cogs for any significant lenght of time will acclerate drive train wear.

 

[sergen]

With a triple and 10 speed you can use all but the 2 biggest cogs when in the big ring. More conservative folks might say don't use the biggest 3

Thanks for that. It will make the cadence range more comfortable being able to go from 52x16 to 52x17 rather than to 39x14.

Out of interest, what are people's views on using the large rear sprockets when in the middle 39 ring? I suppose using the biggest 25 sprocket on a 10 speed cassette would be a 'no' due to cross-chain issues but could you get away with using 39x23 (the 2nd biggest sprocket)?

 

[artmichalek]

Thanks for that. It will make the cadence range more comfortable being able to go from 52x16 to 52x17 rather than to 39x14.

Out of interest, what are people's views on using the large rear sprockets when in the middle 39 ring? I suppose using the biggest 25 sprocket on a 10 speed cassette would be a 'no' due to cross-chain issues but could you get away with using 39x23 (the 2nd biggest sprocket)?

It's doable, but not ideal. The middle ring on a tripple is the same distance off center as the big ring on a double.

 

[sergen]

It's doable, but not ideal. The middle ring on a tripple is the same distance off center as the big ring on a double.

So would you get away with using 39x21 in on a 10 speed 12-25 cassette? I'm trying to understand what the 'safest' big sprocket would be to use before cross chain issues developed on the middle 39 ring.

 

[boudreaux]

So would you get away with using 39x21 in on a 10 speed 12-25 cassette? I'm trying to understand what the 'safest' big sprocket would be to use before cross chain issues developed on the middle 39 ring.

You also have to throw chainstay length into the mix.

 

[Don Shipp]

With a triple some ratios are duplicated. I find that running a small ring to a small sprocket seems to be more efficient than running a large to large with the same development. I assume that this is something to do with the tension in the chain, I don't worry too much about alignment if nothing is rubbing.
(Touring bike with long stays.)