what's the big deal with 10sp?

Well, remember that not all of those cogs are really usable from any one chainring. For example, on my 20-speed road bike (2 at the front, 10 at the rear, obviously), I rarely (if ever) use the three largest rear sprockets when on the big chainring, and I rarely use the three smallest ones when in the small chainring - those "crossed" ratios are unnecessary, less efficient and not very good for the drivetrain. So effectively, a ten-speed system equates to only seven usable rear speeds per chainring. So the difference between 9 and 10-speed is essentially the difference between 6 speeds per chainring and 7 speeds per chainring. Still fairly subtle, but it all helps when you're trying to optimise your efficiency and get your cadence as spot-on as possible.

The other consideration to bear in mind is that having that extra sprocket gives you the option of having a wider gearing range without sacrificing gear spacing - this might mean you can get away with a double instead of a triple chainset.

It could also be argued that because the narrow 10-speed chain has less distance to jump between sprockets, rear shifts are faster and take less effort than with wider-chained systems, although for many the difference is not noticeable, and it is true that 10-speed systems are fussier with regard to adjustment than systems with fewer speeds, where one has greater margin of error.

Quoted post said:

Originally posted by mjw_byrne
So effectively, a ten-speed system equates to only seven usable rear speeds per chainring.

BS

Boudreaux, why BS?

I think that most would agree with mjw_byrne that, although you could use a 53x23, most prefer not to (simply looking at the chain line in that kind of gear is painful for me, let's not even think what it is doing for the chain). 🙂

I would think that if one insisted on using those kinds of cross-overed gears, that efficiency and chain life would suffer quite a bit.

Just curious...

Quoted post said:

Originally posted by boudreaux
BS

Yeah, I thought you might say something like that. That's a bit rich coming from the guy who's constantly telling people they can get away with a short cage mech on a drivetrain with too large a total wrap requirement as long as they stay out of the big/big and small/small gears etc. Everyone knows it's bad practice to use the ratios in which the chain is unnecessarily bent. So how exactly am I talking BS?

Quoted post said:

Originally posted by Powerful Pete
I would think that if one insisted on using those kinds of cross-overed gears, that efficiency and chain life would suffer quite a bit.

Yep, you're exactly right - use your bike with the chain on big/big and technically it'll work, but the drivetrain'll probably sound really rattly and unhappy. With a straight chainline, something around 53x15, for example, it should be silent (providing it's all set up properly of course).

Quoted post said:

Originally posted by mjw_byrne
Everyone knows it's bad practice to use the ratios in which the chain is unnecessarily bent.

I read once the report of a lab test that proved that the difference in wear is not noticeable even after *a lot* of kilometers. I'll try to find that link.
I don't use the big chainring/big sprocket combination, but with my 12-27 cassette I've no problems using the 52x24. Absolutely no noise and no extra wear.

Well, obviously these things vary from bike to bike - there are loads of variables, like BB axle length, whether you use double or triple chainring, chain type and so on. In my house there are 4 bikes (2 are mine, 2 belong to my roommate), and none of them is happy with the chain on big/big. And yes, they are all properly adjusted and set up and in good working order.

Quoted post said:

Originally posted by mjw_byrne
So how exactly am I talking BS?

It's the attitude. He goes sarcastically weirdo with anyone that threatens 'boaudreax wisdom'(? ego perhaps).

Like what someone else said... it's quite boring and tiring that should be dropped. But he thinks it's cool... pathetic eh?:eek:

Quoted post said:

Originally posted by mjw_byrne
Yeah, I thought you might say something like that. That's a bit rich coming from the guy who's constantly telling people they can get away with a short cage mech on a drivetrain with too large a total wrap requirement as long as they stay out of the big/big and small/small gears etc. Everyone knows it's bad practice to use the ratios in which the chain is unnecessarily bent. So how exactly am I talking BS?

You got it wrong, which is par for the course. Only the big/big which ya shouldn't be in anyway, and the smaller cogs when in the granny if you have an issue with insufficient chain WRAP with the short cage. Ya don't really need the smaller cogs with the granny in any event. Ya see, your comprehension just isn't up to par. Triples, having a different chainline than doubles also suggest the more prudent use of crossovver situations,but your original BS dealt with doubles. ...How about defning 'unnecessarily bent'.

Quoted post said:

Originally posted by frenk

I don't use the big chainring/big sprocket combination, but with my 12-27 cassette I've no problems using the 52x24. Absolutely no noise and no extra wear.

That sounds about right.

Quoted post said:

Originally posted by mjw_byrne
Well, obviously these things vary from bike to bike - there are loads of variables, like BB axle length, whether you use double or triple chainring, chain type and so on. In my house there are 4 bikes (2 are mine, 2 belong to my roommate), and none of them is happy with the chain on big/big. And yes, they are all properly adjusted and set up and in good working order.

Now you are backpedaling.

Quoted post said:

Originally posted by boudreaux
Now you are backpedaling.

LOL 🙂

Quoted post said:

Originally posted by boudreaux
...the big/big which ya shouldn't be in anyway...Ya don't really need the smaller cogs with the granny...

Well this fully supports my point that you don't realistically get 10 usable speeds per chainring with a 10-speed system. Personally, I reckon about seven speeds per chainring are viable out of the ten (on a double). Does this apply to every bike under the sun? Not necessarily, but then I never said it did.

Quoted post said:

How about defning 'unnecessarily bent'.

OK, I define the chain to be unnecessarily bent when there exists a different gear combination on the drivetrain that (a) produces a straighter chainline and (b) gives a ratio similar enough not to adversely affect the rider's performance. For example, on a drivetrain with a 10-speed shimano 12-25 cassette and a 52/39 chainset, 39x12 and 52x16 produce the same ratio, but the chainline is better in 52x16. So the 39x12 combination is unnecessarily bent. I would have thought this kind of thing would be obvious to anyone with an ounce of common sense.

Quoted post said:

Originally posted by boudreaux
Now you are backpedaling.

I'm merely acknowledging that what I say is only based on experience and what I've read, and that I acknowledge there may be counterexamples. Unlike some, I am not under the impression that I'm the last word in cycling know-how. Besides, I only said the drivetrain would be unhappy in big/big, and this is not the gear that frenk was describing using.

Seems to me that I agree with the original point . A 9 is a bit better than an 8 for example but much more sensitive to set up and component wear so just how difficult is it going to be in a few years when a 10´s had a bit of time to wear ? Now the pros can change chains / rings / pinions everyday but what about the average people out there ? you know the one´s with a wife , kids and morgage to have to pay for ( and high tech gets more expensive every year ) , how about trying to buy a bike for a teenage kid ? most of us can´t afford high tech - we but the best we can then live with it for a long time , even replacing tyres can be a problem at times : and remember they sell a lot more Tigra and 105´s than Durace , wonder why ?

Yep, that's all true - having more speeds is nice but the high-tech stuff is usually fussier and often easier to screw up. Maybe that is why singlespeeds/fixed gear bikes are often used for commuting. But even if you have the wife, kid, mortgage etc., if you're a real enthusiast and you know what you're doing, the benefits of having those extra features may well be worth the extra time and hassle.

Quoted post said:

Originally posted by mjw_byrne
Besides, I only said the drivetrain would be unhappy in big/big, and this is not the gear that frenk was describing using.

NO! You said with a 10 speed double you only had 7 viable rear cogs per chainring. I think you must be having a brain malfunction.

Quoted post said:

Originally posted by mjw_byrne
Yep, that's all true - having more speeds is nice but the high-tech stuff is usually fussier and often easier to screw up. Maybe that is why singlespeeds/fixed gear bikes are often used for commuting. But even if you have the wife, kid, mortgage etc., if you're a real enthusiast and you know what you're doing, the benefits of having those extra features may well be worth the extra time and hassle.

Seems to me a guy won the Tour several times with 9 speed, competing against other top pros riding 10 speeds . And yeah, don't forget cost in your time and hassle barnyard formula.

Quoted post said:

Originally posted by mjw_byrne




OK, I define the chain to be unnecessarily bent when there exists a different gear combination on the drivetrain that (a) produces a straighter chainline and (b) gives a ratio similar enough not to adversely affect the rider's performance. For example, on a drivetrain with a 10-speed shimano 12-25 cassette and a 52/39 chainset, 39x12 and 52x16 produce the same ratio, but the chainline is better in 52x16. So the 39x12 combination is unnecessarily bent. I would have thought this kind of thing would be obvious to anyone with an ounce of common sense.

WTF?? That is no valid example in support of your 'only 7 viable cogs pre chainring' in a 10 speed setup. You shouldn't be in the small/small anyway. And, your senario doesn't even take into account variables like chainstay length and chainline... Certainly you should be able to point to some scientifically valid study that defines the angle between chain and cog that results in abuse of equipment that will trash ones stuff sooner than normal wear and tear. Otherwise, it's just more baseless fodder for the manure bin like the tiagra chain dropping and DA duraility hooey.