what's the big deal with 10sp?

I know that 10 speed cassettes give you slightly more tightly spaced gearing, but I am curious why this is a big deal and how useful this really is if you don't race.

It seems to me like mostly a marketing thing to get people to buy new bikes/components and "upgrade" to 10sp if they have a 9sp bike, but I just can't imagine that it would make much of a difference for most riders unless the 10sp drivetrain has other properties (more durable? superior shifting?) that make it a significant advantage over 9sp.

I keep thinking of the scene from Spinal Tap where the guy has an amp that "goes to 11" instead of 10 . I imagine that in 10 years we'll all have 11 cog cassettes (with really narrow chains!).

Do those of you who have "upgraded" from 9sp to 10sp really notice a big difference?

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.

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...

__________________
De Rosa Planet
Campagnolo Per Sempre!
PAOLO BETTINI CAMPIONE DEL MONDO x 2!

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?

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).

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.

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?

__________________
no pain, no gain

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'.

That sounds about right.

Now you are backpedaling.

LOL

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.

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.

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.