Is it just me?

[cycleruk]

Nooo, the hillier the ride the lower the gear I need,and on the descents I need a rest

R2 - That's my philosophy as well.
I don't want to pedal downhill at 50 mph. I want it to last as long as possible.
The only time I pedal downhill, and the easy momentum gain, is when it helps to overcome a small "lump" ahead.

[beardy]

Me too on many rides but on many other rides when I am feeling a bit fresh and it is a shorter ride and the wind is with me then I sometimes have a go for that high max speed.

[reohn2]

..... I want it to last as long as possible.......

Me too,premature descentculation is a problem for some men,though doesn't affect wimmin' unless they're from Essex I believe.....

[MartinC]

........ The marketing men have got you to believe that 3x8=24.

When really it's only 22 due to the one overlap

The perfect numbers of the universe 3x8(which)=22,alls well that gets you to the top of the pile,err I mean hill *



*if the hill's green and far away(more religion)all the better

Right. This miracle of 22 needs explaining. You have a 3x8 transmission that gives you 22 distinct ratios without any crosschaining?

We need some definitions here. To me, avoiding crosschaining (on an 8,9,10,11 speed width cassette) would mean losing 2 sprockets for each chainring. If your definition is more relaxed than this then I don't see why you'd think there would ever need to be crosschaining on a 10 speed compact. You can't have it both ways at once.

Duplicates. To me, in a touring context, any gear within 0.2 metres of another is a duplicate not a distinct ratio.

So 3x8 might equal 16 if you're lucky.

[MartinC]

Nooo, the hillier the ride the lower the gear I need,and on the descents I need a rest

Yes, this is the working definition of cycle racing - if you pedal downhill then you're racing.

[reohn2]

Right. This miracle of 22 needs explaining. You have a 3x8 transmission that gives you 22 distinct ratios without any crosschaining?

We need some definitions here. To me, avoiding crosschaining (on an 8,9,10,11 speed width cassette) would mean losing 2 sprockets for each chainring. If your definition is more relaxed than this then I don't see why you'd think there would ever need to be crosschaining on a 10 speed compact. You can't have it both ways at once.

Duplicates. To me, in a touring context, any gear within 0.2 metres of another is a duplicate not a distinct ratio.

So 3x8 might equal 16 if you're lucky.

Regarding crosschaining,there will be x/chaining it's inevitable with any dérailleur system but it all depends how much for how long,the longer the more chain wear.
2x8/9/10 will by necessity have more x/chaining and for longer than a 3x8/9/10 if the front rings are chosen carefully in respect of the cassette ratios.

[MartinC]

Regarding crosschaining,there will be x/chaining it's inevitable with any dérailleur system but it all depends how much for how long,the longer the more chain wear.
2x8/9/10 will by necessity have more x/chaining and for longer than a 3x8/9/10 if the front rings are chosen carefully in respect of the cassette ratios.

That's a politicians answer!

The question was what do you define as X chaining?

[merseymouth]

Hi there, Change has to be necessary, but then it's called Progress! For me the dream cassette would be 15t - 28t 9 Speed, plenty of wraparound with the chain & sprocket. Coupled with a 42t - 32t - 24t chainset I'm in heaven on my tricycle. I ain't racing so I'll happily freewheel down hill or with a tail wind. TTFN MM

[reohn2]

......The question was what do you define as X chaining?

Where the chainring and cog aren't in perfect alignment and therefore the chain has to run out of alignment.
That's the technical answer,however that is almost always the case with dérailleurs,so technically all but for a few ratios,x/chaining is unavoidable.
There are hoever degrees of x/chaining,slight,medium and extreme,all three will be experienced with a dérailleur system,but what really matters is how extreme and for how long.
What I saying is that a two chainring system will experience more extreme x/chaining for longer and because of that and it's lack of chainwrap(less chain on less teeth) wear will be more on such a system,because of that chains,cogs and chainrings will wear quicker.
Also theoretically a narrower ie; 10sp chain and thinner cogs and chainrings, will wear quicker still.

Definitive enough?

EDIT:-BTW to clear up any misunderstanding that may have occurred.
On the other thread you mention compact doubles,I define such chainsets where the inner ring is no less than 34t,ie; 110BCD.
I'm specifically debating Alpine doubles where the minimum inner is 24t to 26t,and the outer is say 38t to 42t,to give a workable loaded touring range.Such chainsets are usually(though not exclusively) made from triple c/sets by using the two inner ring positions only(sometimes with a chain guard fitted in place of the outer ring),such c/sets make for even worse x/cross chaining unless a significantly longer BB axle is fitted to bring the two rings further outboard for better c/ring alignment,but with that comes a wider Q.
Obviously if the chainset is a specific Alpine double(Middleburn/Sram,etc) the Q maybe better,though I haven't checked.

[blackbike]

I find it increasingly frustrating that whatever I buy (not only bike bits) seems to be the last one available. Well I know that's an exaggeration, but the manufacturers seem to be 'redesigning' or 'updating' everything at an alarming pace. Latest example, in May I bought a simple steel 1 1/8 threadless Tange headset with balls, and want another for a second bike.... Not available any more! It's either buy an alloy one or a steel one with cartridge bearings, or a VERY poor quality budget unbranded one. 7 speed cassettes, not available if you want a close ratio, 8 speed seem to be going that way. Maybe I'm a boring old F**t, but I don't want an 11T smallest sprocket either, because the chain runs better on a 13. Maybe I'm wrong, but I don't view 11 speed with a tiny thin chain as an improvement. I suppose I'll not be able to buy alloy bars soon?

Decent 7 and 8 speed stuff and threaded headsets and forks are becoming harder to get. So are older style front MTB shifters that fit to a standard width road bike frame tube made of 531 or other older frame material.

Thank goodness we have the internet or it'd be extremely difficult to buy anything but the latest bits and pieces.

One slight plus is that the lower quality stuff available is not too bad.

My 531 framed winter tourer/everyday bike is fitted with a very cheap and ugly Shimano all steel MTB chainset and a Chinese brand 7 speed cassette. With my preferred bar end levers the shifting is just fine.

[tatanab]

This chap keeps some nice 80s equipment as well as older and newer parts. I've bought stuff from him. http://www.defietsenmaker.nl/index.php? ... me&lang=EN

[fastpedaller]

Maybe I'm a boring old F**t, but I don't want an 11T smallest sprocket either, because the chain runs better on a 13. Maybe I'm wrong, but I don't view 11 speed with a tiny thin chain as an improvement. I suppose I'll not be able to buy alloy bars soon?

While I can see that the 11t sprocket has it's place in a racing set up, there seems little rationale in this size for most other cycling pursuits.
I use MTB cassettes to give me the low gears I want for steep climbs but the 11t seems pretty well obligatory whereas I'd be happier with 14t.
I can overcome the problem to some extent by purchasing an 11-28 cassette and using cannibalized parts, dispense with the 11t and 12t using a 12t 1st sprocket and putting a 32 t at the back of the 28. I'd really like to be able to buy a 14-34 but such a combination doesn't seem to be available.

I agree with you, except that I can't really see the need for an 11T even when racing, as I have done in the past. I think it was Renolds chains who did testing many years ago and found that there are large efficiency losses once the sprocket size goes smaller than 19. That does seem somewhat extreme, but I've certainly found a 13 to be about as small as I would go, and with a larger chainring, this should be possible. NB I've just done a quick check, and for a similar gear where a 52 ring was used, that would equate to a 61 ring if using a 13 instead of 11, so I see your point. However, is this for a sprint? 52x13 at 140RPM = 44MPH, If for a time trial then 90 RPM gives 28MPH. So I still need convincing.

[karlt]

I define crosschaining as when the chain rubs in the derailleur on an indexed system. On a friction system it's whatever I've noticed looks a bit odd on the stand. So on the better bike (50/39/30 x 8sp 12-26) it's bottom two cogs on the big ring, top two cogs on the middle ring and top four cogs on the little ring - so that's a total of 8 out of the 24 theoretical I never use. On the commute bike (52/40 x 8sp 12-30 (was 11-30 but I swapped the 11 cog for a 12 I had lying around)) it's top two cogs on the little ring and lowest two cogs on the big ring - big/big is actually unattainable and I can't be buttocked to lengthen the chain for a combination I never use. So that's 4 out of the 16 I never use.

[MartinC]

......The question was what do you define as X chaining?

Where the chainring and cog aren't in perfect alignment and therefore the chain has to run out of alignment.
That's the technical answer,however that is almost always the case with dérailleurs,so technically all but for a few ratios,x/chaining is unavoidable.
There are hoever degrees of x/chaining,slight,medium and extreme,all three will be experienced with a dérailleur system,but what really matters is how extreme and for how long.
What I saying is that a two chainring system will experience more extreme x/chaining for longer and because of that and it's lack of chainwrap(less chain on less teeth) wear will be more on such a system,because of that chains,cogs and chainrings will wear quicker.
Also theoretically a narrower ie; 10sp chain and thinner cogs and chainrings, will wear quicker still.

Definitive enough?

EDIT:-BTW to clear up any misunderstanding that may have occurred.
On the other thread you mention compact doubles,I define such chainsets where the inner ring is no less than 34t,ie; 110BCD.
I'm specifically debating Alpine doubles where the minimum inner is 24t to 26t,and the outer is say 38t to 42t,to give a workable loaded touring range.Such chainsets are usually(though not exclusively) made from triple c/sets by using the two inner ring positions only(sometimes with a chain guard fitted in place of the outer ring),such c/sets make for even worse x/cross chaining unless a significantly longer BB axle is fitted to bring the two rings further outboard for better c/ring alignment,but with that comes a wider Q.
Obviously if the chainset is a specific Alpine double(Middleburn/Sram,etc) the Q maybe better,though I haven't checked.

To me X Chaining is where the chainline is bad enough to have a substantive effect on performance or on wear rate. To me this is a more usable definition because otherwise everything is always X chained and it becomes meaningless. The problem is that deciding when this has happened is arbitrary. My working definition varies with number of sprockets because a 7 (or below) speed cassette is narrower and a 10 speed (or above) chain is more flexible. So in practice my ratios to avoid are:

7 speed triple:
Outer - largest sprocket
Middle - smallest sprocket, largest sprocket
Inner - smallest sprocket

8 & 9 speed triple:
Outer - largest 2 sprockets
Middle - smallest sprocket, largest sprocket
Inner - smallest2 sprockets

7, 8 & 9 speed double
Outer - largest sprocket
Inner - smallest sprocket

10 speed anything
Outer - largest sprocket
Inner - smallest sprocket

Chainwrap. More is better but a what point it makes a substantive difference is unknown. Certainly small rings and sprockets are best avoided (but if you need them you need them). If you've got an easy choice of the same ratio on 2 chainrings then it's theoretically better to use the one on the biggest ring but I wouldn't waste much (any) time trying to achieve this other than on an IGH, SS or fixed. If you're going to be finicky about chainwrap then to be consistent you'd need to start worrying about even toothed chainrings too, but we don't.

Yes, a normal compact is 34 smallest, 16 tooth difference chainset. MTB or Alpine ones have smaller rings and maybe bigger difference. Any transmission I set up would have a decent chainline and Q factor, it's part of the selection criteria and easy to achieve even if you bodge a 110 /74 triple.

So if I have a 46-30 front, 13-34 9 speed or 12-32/36 10 speed rear double where I only need the 7 sprockets on the best chainline on each chainring how is it going to be substantively any better or worse than an 8 speed triple in terms of average wrap or crossover?

10 speed wear. The internal width (and thus the wearing parts) of a 10 speed chain are pretty similar to 9 speed and below, what's really different is the external width and the way they're pinned. They're just as robust as other chains. Sprockets may be marginally thinner but the biggest difference is in the gaps between them. I'm not sure if chainrings are thinner (I know Campag 9 and 10 speed are the same) but again the gaps between them are smaller. The biggest difference in 10 speed cassettes and chains is the price - they don't seem to wear or break more than older stuff.

[reohn2]

As I posted on the other thread,you have your view,I have mine,and never the twain shall meet it seems.
I'll leave it at that and let others decide for themselves.