Options for lower gearing on tandem

[deluz]

My wife and I are at a combined age of 132 and climbing hills is getting tougher.
I can always just push harder to get up the hill but would be nice to have the option to go easier.
Current gearing is 50/39/28 on front and 12-32 on back 10 speed.

I came up with following option:

1. Change small chain ring to 26T. This would be cheap and easy and give a 7% reduction which might be enough. Currently shifting from 28 to 39 is not super smooth but not bad, not sure if 26 to 39 would be worse. When shifting from 39 to 26 would have to downshift the back first or it would be too big of a jump.
Maybe change the 39T to 38T.

2. Larger cassette. There is not a 12-34 so would have to go 11-34 which would be a 6.25% reduction.
Rear derailleur is SRAM Force rated for 32T so not sure it can work.

3. Change to 12 speed. I see two options here, Campy chorus or SRAM etap.
Chorus has max cassette of 34T, I believe etap can go to 36T.
Both of these would be quite expensive and not sure if it is feasible.
Will a 12 speed chain work on my current chainrings?
Can I run etap on just the rear and keep my mechanical shifting triple on front?
Seems like that would be possible if it works on 1X cranksets.
Getting rid of the rear shift cable is appealing although my current SRAM works very well.

Thanks for any input.

[Dave]

Here's something that I found, just this week. There's a company selling an extended length RD cage that allows a SRAM AXS 10-44 cassette with a Force or Red 2x RD. Combine that with a GRX 48/31 or 46/30 and you get a very low gear ratio. They seem to suggest using a wolf tooth road link too. I tried a road link once and it didn't seem to do a thing with my Force RD. There's a possibility that only a longer B screw might give the necessary upper jockey pulley to big sprocket clearance.

I've used both models of GRX cranks with a 10-36 cassette and stock Force and Rival RDs.


https://cycleschinook.com/product/ro...8IAwLsQNNNkH90

[yinzerniner]

Originally Posted by deluz

My wife and I are at a combined age of 132 and climbing hills is getting tougher.
I can always just push harder to get up the hill but would be nice to have the option to go easier.
Current gearing is 50/39/28 on front and 12-32 on back 10 speed.

I came up with following option:

1. Change small chain ring to 26T. This would be cheap and easy and give a 7% reduction which might be enough. Currently shifting from 28 to 39 is not super smooth but not bad, not sure if 26 to 39 would be worse. When shifting from 39 to 26 would have to downshift the back first or it would be too big of a jump.
Maybe change the 39T to 38T.

2. Larger cassette. There is not a 12-34 so would have to go 11-34 which would be a 6.25% reduction.
Rear derailleur is SRAM Force rated for 32T so not sure it can work.

3. Change to 12 speed. I see two options here, Campy chorus or SRAM etap.
Chorus has max cassette of 34T, I believe etap can go to 36T.
Both of these would be quite expensive and not sure if it is feasible.
Will a 12 speed chain work on my current chainrings?
Can I run etap on just the rear and keep my mechanical shifting triple on front?
Seems like that would be possible if it works on 1X cranksets.
Getting rid of the rear shift cable is appealing although my current SRAM works very well.

Thanks for any input.

Any thought on going to something like a 48/32 or 48/31 front with an 11-40 cassette rear? Grx mechanical supposedly works with some adjustment.

https://velonut.com/blog/shimano-grx...1-40t-cassette

That would get you a similar top end with a .8 gear at the bottom instead of a .875, or roughly 10% lower gear.

[deluz]

Originally Posted by yinzerniner

Any thought on going to something like a 48/32 or 48/31 front with an 11-40 cassette rear? Grx mechanical supposedly works with some adjustment.

https://velonut.com/blog/shimano-grx...1-40t-cassette

That would get you a similar top end with a .8 gear at the bottom instead of a .875, or roughly 10% lower gear.

Cranksets for tandems are really limited. The trend is to use 2X compact cranksets which would be 50/34. Also my wife likes 165mm cranks which are almost impossible to find. DaVinci and
Lightning are the only options I know of.
I was thinking the jumps on an 11-40 would be too big but looking at it not that much different than my current 12-32 10 speed cassette.

[eddief]

I run that and an 11 speed 11-40 crankset on my Di2 Roubaix. On that bike the shifting is perfect. And they do one in 165.

[deluz]

Originally Posted by eddief

I run that and an 11 speed 11-40 crankset on my Di2 Roubaix. On that bike the shifting is perfect. And they do one in 165.

That Praxis crank would be great but do not appear to make tandem cranksets

[Tall]

Originally Posted by deluz

1. Change small chain ring to 26T. This would be cheap and easy and give a 7% reduction which might be enough. Currently shifting from 28 to 39 is not super smooth but not bad, not sure if 26 to 39 would be worse. When shifting from 39 to 26 would have to downshift the back first or it would be too big of a jump.
Maybe change the 39T to 38T.

We run 52/42/26 (or 24? I'd have to look) on our tandem. Yes, it's not exactly a smooth shift in either direction -- you have to plan ahead and not bail onto the small ring too late. I think with your 39 small ring you should be okay. After all, this is going to be a somewhat infrequent shift.

[eddief]

about tandem stuff. should have been smarter. next time.

Originally Posted by deluz

That Praxis crank would be great but do not appear to make tandem cranksets

[Gabe77]

On my prior do-all bike I tricked out the 105 triple 50/39/30 with a 24T granny. It does shift with STI levers - but you do have to finesse it a bit, but I haven't tested it under full load etc - especially with a 2nd body on the bike.
Apart from the above - getting a "roadlink" hanger extender for the RD is the goer - then just use a bigger cassette. In 10SP you could get up to 36T with XT cogsets. That's the cheapest way to do it I can think of. Even more useful if you splice it to remove the top gears with something sensible like a 14T start junior cassette.

[deluz]

Originally Posted by Tall

We run 52/42/26 (or 24? I'd have to look) on our tandem. Yes, it's not exactly a smooth shift in either direction -- you have to plan ahead and not bail onto the small ring too late. I think with your 39 small ring you should be okay. After all, this is going to be a somewhat infrequent shift.

I looked at my RD and there seems to be a good amount of clearance between the jockey wheel and 32T cog.
So I am thinking it might be possible to use 12-36 cassette if I adjust the B screw in. If not I can always try a road link.
I am debating whether to try the 26T ring first or the 12-36 casette.
Changing the cassette would give me 12% lower gear and changing the chain ring would give me only 7% lower gear.
With the cassette change I would loose the 14T cog, so the jump from 13T to 15T would be pretty big.
I am sure not we use those gears that much, we tend to use the upper half of the cassette more.
I looked for a 26T chainring and there are not a lot them. I found an old Salsa ring that I think is the same as the one I have on now but the color doesn't match which is not a big deal.
There is the TA Zelito that says it is 10 speed compatible but not sure it worth twice the price of the Salsa.

[fogrider]

would the Wolf Tooth roadlink work to get more range on the rd? https://www.competitivecyclist.com/w...8aAr0NEALw_wcB

[truth]

Shimano has a 10 speed 11-36 cassette that works fine with road compact doubles and GS derailleurs. I imagine you've got an SGS derailleur and it would work fine with this cassette. A roadlink could help as well.

I'd do that and a smaller front chainring.

[yinzerniner]

Originally Posted by truth

Shimano has a 10 speed 11-36 cassette that works fine with road compact doubles and GS derailleurs. I imagine you've got an SGS derailleur and it would work fine with this cassette. A roadlink could help as well.

I'd do that and a smaller front chainring.

OP clearly stated that he’s using a Force RD with 32t stated capacity. In that case it can definitely handle 34t, and possibly 36t without any alteration

Even if it doesn’t work perfectly with 36t, replacing the stock b screw with a longer replacement from the local hardware store. That’ll push the top pulley down a bit when it’s shifted to the last cog.

Worst comes to worse, if the op cannot find a tandem crankset that works with larger range 11s or 12s groups he might try a grx 10s shifter and derailleur combo. Not sure how well the front chainrings would shift but the rear definitely works with 11-36 cassette, if not 11-40 from sunrace or the like.

[palincss]

Originally Posted by deluz

1. Change small chain ring to 26T. This would be cheap and easy and give a 7% reduction which might be enough. Currently shifting from 28 to 39 is not super smooth but not bad, not sure if 26 to 39 would be worse. When shifting from 39 to 26 would have to downshift the back first or it would be too big of a jump.
Maybe change the 39T to 38T.

If you're going to a small granny ring, why stop at 26? Why not 24?

As for the shift in the rear to compensate when you go to the granny, you're going to have to do that anyway, but it's done by shifting to the granny first, then upshifting the back, not the other way round. You can sometimes manage to do both at the same time.

Going the other way, from the granny to the middle chain ring, most of the time you can do the chainring shift first, then downshift the rear to compensate since typically you're still in what qualifies as a low gear when you cross to the middle ring.

[Deanhorsfall]

It seems that most of us would suggest a double compact crankset, a 1x drivetrain or a wide range cassette. One thing that a few people like are sub compact cranksets. Velo Orange have a few options which are inexpensive and come in 165mm- I think one of your big problems now is the 39 tooth middle ring.
https://velo-orange.com/collections/...kset-24x34x48t