fooferdoggie 

on our tandem its a flat bar setup with shimano deore 1 finger brakes and I think xt 10 speed shifter. but as it gets colder it gets harder to shift especially with gloves. the housing is standard Shimano housing about 2000 or so miles on it maybe 1 year old. Shifting was fine two weeks ago till it started getting around 40 degrees or less. I don't know if I changed it over to say jagwire would help or not. My mechanic is thinking a twist shifter. But I am not sure if it would fit with the brake lever or not since the sifter fits under the brake.
He thought maybe switching over to sram would give me a better choices. I have a dt Swiss hub on back so it's not hard to change it over to sram though I guess I would have to go to 11 or 12 speed? Any other ideas? not the greatest pic I will get a better one tomorrow. but the setup is pretty standard but I use bar tape instead of grips.

Steve B.

My solution to chronic thumb issues, due to years of work related injuries, and when I had a very difficult time using XT and SLX shifters, was to switch to electronic shifting. Expensive solution but allows me to mt. bike without issues.

79pmooney

Before I did anything else I'd see what I could do to absolutely minimize drag on the cable. Disconnect it at the RD and see if it slides easily through the housing. Maybe pull it out and lube with Dri-Slide. (The graphite stuff. I haven't bought it in decades so I might have the name wrong.) Or TriFlo. Look for any kinks in the cable run. Pull the cable out and open each cable housing end up with a "pokey tool" (sharpened spoke bent to a handle at the other end. A Portland staple. I staple pieces of housing to my tool board for those pokeys.) Maybe file the housing ends square to ensure clean runs. Grease the BB cable guides with something like Phil Wood. (Appropriate for your weather, road grit and temperatures.) Lube the derailleur parallelogram pivots.

You might also try re-connecting the cable at the RD but with an inch or so of slack. Now see if you can grip the cable up by the shifter with pliers and see how hard it is to move the RD. Are you fighting something that shouldn't be there?

Shifter - has it changed in the cool weather? Wrong lube? Maybe Dri-Slide or TriFlo for the winter.

Hands - better, warmer gloves? (I have an old injury to the base of my thumb. Barely works, what with the pain on cold days.)

All this costs you a spoke or two and about 50 cents of lube. Maybe a pair of gloves. When that fails, OK, it's time to take on the bigger stuff. Or maybe you really don't like thumb shifters and this is a good excuse to change. I have no opinion here. Just one who likes finding the easy and good solution when it's there.

FBinNY 

Temperature shouldn't materially affect shifting. It is possible that the housing is worn --usually at the rear loop-- or the wire is fraying up near the lever, so check for a mechanical problem.

You might also bring the bike in for a while and see how the shifting feels at room temp.

If the bike checks out, it might be that the cold affects your hands somehow.

Before spending more than a few dollars, I'd try improvising some sort of extension for the lever. Just as a test, maybe an ice cream stick secured by winding on thread like on fishing poles, or whatever you can come up with.

If that helps, then you can try to improve on the concept. OTOH, if it doesn't work, a twister should be easier to use with gloves.

fooferdoggie 

gloves make it harder to shift it seems. but the days have been changing in temps a lot and it seems a bit easier when it is warmer. I will check the housing and see. shifting is pretty good and smooth and accurate.
I ride a lot a day and shift a lot. my commuter has the same setup. about 30 miles a day so it's a lot of shifting. but it only started to bother me as it got colder. I can usually only shift one gear at a time when it is cold on the tandem. it's always been harder to shift on it than my other bikes because of so much housing.
I would like to go to electronic shifting but it may be awhile till I can swing it. I will take the wire loose and see how it moves. would jagire housing and cable be a better choice than the Shimano standard? it will been the 50s in the afternoons so I may be able to check it.
I just don't know if the twist will work with the brake lever though? that would be the cheapest solution but I may have to go to sram for it. but I dontt have a way to check the compatibility.
so far I have only needed light gloves and they are fine on my commuter bike and my electric gloves are fine on the commuter. though I have not used them on the tandem yet this year.

Crankycrank

The shifting hardware should not be much, if any, harder to operate in 40deg temps. If it gets around freezing moisture can freeze up in your cables/housing making it harder to shift. Is your bike stored in freezing temps at night? If so, it might take a while to thaw out the cables during your ride.

FBinNY 

Before making a big change try keeping your hands warmer.

Cold definitely makes muscles weaker, or at least feel that way.

fooferdoggie 

I do I have three different pairs of gloves. just got some gore-tex active light gloves that are good to around 42 degrees some lobster claws good to around 39 degrees and my electric gloves good to about 30 or less. so I carry all three with me now so I can choose. but in the mornings on my commute where is far colder I don't really have issues on my other bike. but the tandem in the lower 40's it seems far harder. its always more work then my commuter but its really harder now.

maddog34

https://www.ebay.com/itm/30368593366...Bk9SR_qZ1cSQYQ

https://www.ebay.com/itm/18509644337...3ABFBM6OjgxJBh

If by "hard to shift" you mean Slow, gummy feeling, then try lubing the shifter..

the modern Lined cable housings don't require lubing if you use the good cables.

Ross200

You might have two issues to address:

Lots of help for cold hands if you go ice biking!
One example-
https://barmitts.com/products/mounta...gies-flat-bars

As the temperature drops, gloves are not your friends.

Deferred maintenance and wrong choice of shifter. In my experience, the effort need to shift a tandem is the same at +20F as at +50F in a properly serviced system. New cabling is always good for a tandem. But if you have cold hands, integrated shifters that require a thumb push really limit your choice of hand wear. My Raynauds is getting worse as I age and all my flat bar winter bikes have old time thumb shifters you can shift with the palm of your hand while wearing mittens. You get creative commuting at -40 F!

New cables, cleaned shifters and barmitts with thin gloves might make you a happier camper-

AeroGut

As mentioned above, old style thumb shifters that are above the bars are nice because you can shift with your palm if your thumb is having trouble. Micro shift sells a 10 spd one: https://www.microshift.com/models/sl-m10-r/

dedhed

https://www.rei.com/product/179848/4...B&gclsrc=aw.ds

fooferdoggie 

it almost never gets below 30 degrees here. so the electric glove works great. they give me a lot of a range in temps. its just not practical to use the bar covers too many things on my bars. but I don't think the cold makes my thumb hurt I think its more of my light carpel tunnel acting up.

Lombard

I would first replace your shifter cables and housings. That is the lowest hanging fruit and if the bike is a few years old, there is probably some friction due to housing wear and cable oxidation. Make sure you replace the cables with good quality stainless steel rather than the cheaper galvanized cables that become rough and cause more friction.

If that doesn't solve the problem, I would switch to twist shifters.

dedhed

I used to have that problem on my deore thumb shifter. Lubed it up with some lighter lube, good to go. Don't forget to lube the derailleur pivots as well. Every bit of thicker lube in the system becomes stiffer as the temperature drops.

CliffordK

I was thinking something similar with putting bar end shifters into the bar extensions.

Then one can just grab them with the whole hand.

fooferdoggie 

ya I may not have lubed them after the last couple of rain rides too.

fooferdoggie 

I tried moving th wire by hand and its so stiff I could hardly move it. so time to change the housing and cable. I was going to take the housing out and get some jagwire cut to length but I don't want to deal with the in and out of the frame so I took it to thew trek shop its less then a mile away. I may buy the park tool for this but maybe not and just let the shop do it.

CliffordK

Make sure you get non compressible plastic/teflon lined shifter cable housing. Usually has wires running lengthwise.

fooferdoggie 

yes getting the Jagwire housing and their coated cable. the cables like 30.00 or so but should be well worth the cost.

RCMoeur 

On the front of our tandem, we have the bar end shifters in the tops of... the bar ends. Given that captaining a tandem can be a busy task, it's nice that I can shift when needed using a thumb, finger, palm, or any other convenient extremity.

djb

I'm a cold weather rider (Canadian winter) but as you've discovered that its a real housing cable issue, all the temp stuff is a moot point.
What I did want to strongly suggest is concerning getting a really good quality housing and cable cutter-- years ago I finally bought a Parks cutting tool, and it was one of the best purchases you can get.
Firstly it works well and keeps working well, but the BIG side benefit is that having it means that you are less likely to let a bike get like your tandem is, because it will become less of an ordeal to change housings and cables, and you tend to be more intimate with your bikes mechanical stuff when you actually do it yourself.

BUT I totally get not wanting to deal with internal routing. None of my bikes have this, so its not a joy that I have yet to struggle with. I've in fact refused to do a friends bikes housings cables as a favor when I saw it was internal, as I knew it could very well become a frustrating situation. There surely are tricks to dealing with it, and some frames are most likely easier than others.

that said, having a Parks cable housing cutter is never going to be a bad idea, especially if you have other bikes.
but if you aren't into doing stuff on your own, thats perfectly fine too of course.

Lombard

They key here is that the Park cutting tool will to some degree prevent the housing end from becoming off-round. Though you may still need to reem the end out after cutting to prevent the end from being a point of cable friction.

I have one bike with internally routed cables. It is a royal PITA to change cables. Sure, there are tricks, but it still takes much longer and more curse words to change cables on this bike than any of my externally routed cable bikes.

Schweinhund

Why? Just create some slack in the cable by shifting into the largest cog in the rear and pedaling until the derailleur shifts, then return the shifter to the small cog position. don't pedal and shift. you have slack now, proceed. you can pull the housing out of the stops without disconnecting the cable or pulling it out of the housing when you lube it.
reverse to re-assemble.

djb

Ya, I always use an awl to go over the cut area, sometimes its not really needed, but I do it anyway.
I've also had to get a file and file off a bit of the coiled metal that just is in the way a bit, so its never as simple as cutting with one cut and thats it.
I dont know any better, and its perhaps my technique, but the awl for 5 seconds and or a bit of filing is fast, so thats what I do, but Im not a paid mechanic, just joe blow public at home.

and yes, I have to say I have no real urge for a frame with internal routing, and am happy with full length housing on my heavier tourer, it just simplifies things.