Tandem Cycling - 10 speed possible with 145 mm rear?

Three bike dealers near me all differ on this question. I asked whether I could just buy from Santana one of their 11 to 34 rear cassettes, which they put on this webpage
http://www.santanatandem.com/perfect10.html
on 2 November '05 and put it on a newish Co-Motion with 145mm rear which currently has a 9 speed Shimano cassette and triple in front. One dealer says it won't work, 2nd says it will but won't work well; 3rd says it will work fine with the right chain. Obviously I turn to the experts here for the final word!

Shimano's 10-speed cassettes fit on all 8- or 9-speed Hyperglide Freehubs, so there is no issue with respect to rear hub compatibility. Obviously, you'll need to change shifters to make use of the 10 speed rear cassette; however, your rear derailleur should work just fine assuming it is a long-cage model that was already being used with an 11x34t rear cassette.

As to whether or not you will encounter any chain interference with the right rear chainstay when using the 11t cog with your large chain ring, going from memory I seem to recall that the rear-drop out area is fairly roomy so if you don't have issues with the 9 speed cassette I don't believe there will be any issues with the 10 speed cassette. However, rather than looking for consensus I would suggest you simply call Co-Motion and ask.

I'm not sure what the value would be. If you were talking about a time trial bike with straight block, i.e.- every shift just one gear, then the additional gear would be a big deal. Going from an 11-34 9sp to 11-34 ten speed isn't really that big a deal, considering the costs, unless you have to replace the 9sp stuff anyway. Even then, ten sped si a ;lot more than 9sp. TandemGeek has it straight about the tech issues. p.s.- you need better dealers!!!!!

you need better dealers!!!!!

Ain't that the truth...

I thought the advantage of more speeds in the drivetrain was only partially the gear range. In fact, most of the 10-speed road cassettes have a much narrower range of gears than most of the Mega-9 cassettes on tandems. As I understood it, most of the advantage comes from the smaller difference in gear ratios from one gear to another, allowing for smoother shifting response to the terrain, etc.

It does seem like quite the cash outlay to upgrade to 10-speed, but hey--the cool factor is significant!

DrPete

Co-Motion puts out 10-speed set ups and has not changed their 145 spacing. You will need 10 sp. brifters, narrower chain & cassette. Chain line will not be as good as with the 9 speed.
Big bucks and not really an upgrade, in our opinion.
However, the option is there!

Visit Sheldon's page (http://sheldonbrown.com/speeds) on the subject. Basically, 8, 9 and 10-speed cassettes fit onto the same freehub (except the 10-speed Al Dura Ace cassette and freehub), so it will fit on the hub.

However, I find that seatstay clearance is really tight with 9-speed and 12-15 as the smallest two cogs. Since the 10-speed cassette is 0,5 to 1 mm wider overall, I presume the cassette will fit if you have relatively small cogs to the right. In other words, 11-12 or 11-13 will fit, but 12-14 or 13-15 might scratch some paint.

But as others have said, unless you need to change your shifters for whatever reason (or want to use your bar-end shifters in friction), that's an expensive change.

Visit Sheldon's page (http://sheldonbrown.com/speeds) on the subject. Basically, 8, 9 and 10-speed cassettes fit onto the same freehub (except the 10-speed Al Dura Ace cassette and freehub), so it will fit on the hub.

However, I find that seatstay clearance is really tight with 9-speed and 12-15 as the smallest two cogs. Since the 10-speed cassette is 0,5 to 1 mm wider overall, I presume the cassette will fit if you have relatively small cogs to the right. In other words, 11-12 or 11-13 will fit, but 12-14 or 13-15 might scratch some paint.

Michel,
Thanks. I knew (well, recently learned) that the 10 speed cassette would fit on the same freehub, but I didn't know that it was a bit wider. I assumed they were same width. When you say clearance is tight, what model of tandem are you referring to?

Well, can't say I am serenely above the "cool factor" appeal. But I was thinking that 10-speed will be the new standard so might as well accept it. Also, the newest Ultegra 2005 10-speed STI levers have more trim positions for the front so was thinking about those. Not sure if Shimano introduced 9-speed STI in 2005 with this additional "nudgeability". This is what I have heard but I may well have got the wrong end of the stick.

Of course you get smoother shifting, but how much so? It appears that the proposal here is to go from one 11-34 to another. If the proposal was from a 9sp 11-34 to a ten speed 12-25, now that would really smooth things out. BUt my point would be that nearly the same change wold be had by going to a 12-25 9sp. I took the 11-34 off my Cdale starter bike and have a 12-23 now. Same 9sp gruppo. Now that really smooths things out and I can actually use the granny gear now. Cost me nothing as I had the cassette. I've got DuraAce ten sp on my racing bike and there is some value to the updated stuff. But I don't think you're getting a lot for your money making this sort of change uless the drivetrain is worn out and needs replacing anyhow. I don't really think most folks need a 11-34 cassette, unless you're hitting some really big climbs. In racing, changing your gearing is as common as changing your tires, maybe moreso. I gear the bike for the course every time by changing the cassette. Same can be done here: buy a cassette with a better range for your uses and see how it goes. Cheaper than STi levers....

I'm just waiting for SRAM to release a road group. The X.0 drivetrain I had on my mountain bike was by far the best I've ever used, road or mountain. The problem is their derailleurs won't mix and match with Shimano shifters because it's a different actuation ratio...

Hear that, SRAM? We're waiting... :)

DrPete

Chain line will not be as good as with the 9 speed.

However, the option is there!

I don't understand why this would be. The width of a 9speed cassette and the 10 speed cassette are essentially the same, so the chain line wouldn't appear to change .

It was stated in the thread that the 10 speed is .5 to 1mm wider, this wouldn't seem to effect the chain line in any material fashion.

Also, its my understanding that the 10 speed cassette is actually narrower than 9 speed. When you put a 10 speed D/A cassette on a 9 speed hub, you have to add a spacer to take up the extra space.

Michel,
Thanks. I knew (well, recently learned) that the 10 speed cassette would fit on the same freehub, but I didn't know that it was a bit wider. I assumed they were same width. When you say clearance is tight, what model of tandem are you referring to?


My tandem is a Co-Motion Primera; it came with a 11-32 cassette, but I quickly installed a home-made cassette with the following: 12-15-16-17-19-21-23-26-32. When the chain jumps from 12 to 15, I find it goes fairly close to the curved seatstay, but not too close for comfort. But add 0,65 mm to the width of the cassette and it might be very close, unless you get smaller small cogs. With the stays curvature, I think that 11-12 or 11-13 would work perfectly.

As for cassette width, I read measurements from Sheldon Brown's page (http://sheldonbrown.com/k7.html#spacing).

A 08-speed cassette has 1,80 mm sprokets and 3,00 mm spacers.
A 09-speed cassette has 1,78 mm sprokets and 2,56 mm spacers.
A 10-speed cassette has 1,60 mm sprokets and 2.35 mm spacers.

So, counting 8 sprokets and 7 spacers for the 8-speed cassette,
a 08-speed cassette is 35,40 mm wide,
a 09-speed cassette is 36,50 mm wide, and
a 10-speed cassette is 37,15 mm wide.

.65mm. I can't believe that is going to be a noticeable difference in chain line. Moreover, the 10 sp will give you one more useable cog in the middle of the cassette, reducing slightly the use of cogs at either extreme on the cassette.

My tandem is a Co-Motion Primera; it came with a 11-32 cassette, but I quickly installed a home-made cassette with the following: 12-15-16-17-19-21-23-26-32. When the chain jumps from 12 to 15, I find it goes fairly close to the curved seatstay, but not too close for comfort. But add 0,65 mm to the width of the cassette and it might be very close, unless you get smaller small cogs. With the stays curvature, I think that 11-12 or 11-13 would work perfectly.

As for cassette width, I read measurements from Sheldon Brown's page (http://sheldonbrown.com/k7.html#spacing).

A 08-speed cassette has 1,80 mm sprokets and 3,00 mm spacers.
A 09-speed cassette has 1,78 mm sprokets and 2,56 mm spacers.
A 10-speed cassette has 1,60 mm sprokets and 2.35 mm spacers.

So, counting 8 sprokets and 7 spacers for the 8-speed cassette,
a 08-speed cassette is 35,40 mm wide,
a 09-speed cassette is 36,50 mm wide, and
a 10-speed cassette is 37,15 mm wide.And if the 10 speed cassette is actually wider, than why do they come with a thin spacer that has to go on the 8/9 hub body first to keep the cassette from being a sloppy fit?

Honest answer: no idea.

And if the 10 speed cassette is actually wider, than why do they come with a thin spacer that has to go on the 8/9 hub body first to keep the cassette from being a sloppy fit?

The low gear sprocket cluster on a Shimano 10 speed cassette uses a deeper offset than the 9 speed clusters that places the tallest (lowest) 10 speed cog closer to the hub body & spokes. The shortest (highest) cog sits in the same position as it does with a 9 speed cassette.

The spacer is needed when using a 10 speed cassette on a 9 speed cassette carrier to remove the slack and to keep the cassette from binding against the hub body. As you would suspect, because of this off-set, the 10 speed hub cassette carriers are narrower than the 9 speed cassette carriers.

The width of a 9speed cassette and the 10 speed cassette are essentially the same, so the chain line wouldn't appear to change.

The chain line is, for all intents & purposes, the same on 9 speed as it is on 10 speed.

The low gear sprocket cluster on a Shimano 10 speed cassette uses a deeper offset than the 9 speed clusters that places the tallest (lowest) 10 speed cog closer to the hub body & spokes. The shortest (highest) cog sits in the same position as it does with a 9 speed cassette.

The spacer is needed when using a 10 speed cassette on a 9 speed cassette carrier to remove the slack and to keep the cassette from binding against the hub body. As you would suspect,[b] because of this off-set, the 10 speed hub cassette carriers are narrower than the 9 speed cassette carriers.[b]But a 8/9 cassette still fits on a non Da 10 hub body.

But a 8/9 cassette still fits on a non Da 10 hub body.

Probably true and probably should have specified Dura Ace in my earlier posts as I haven't fiddled with anything else in Shimano's 10 speed line.

With the exception of their 9 speed cassettes and front derailleur on our Ventana, I don't use Shimano so I'm only mildly conversant in Shimano technology.

Three bike dealers near me all differ on this question. I asked whether I could just buy from Santana one of their 11 to 34 rear cassettes . . .

Better late than never (registration has been closed until recently): All three dealers got it wrong!
According to Gerard (Santana), the "Perfect 10" (TM) cassette is not available for after-market sale.
Santana's inventory is reserved for current production. :(

--Gary, in rainy Carmel-by-the-Sea