The Art of Shifting on a Tandem

[dulongj]

You would think with over 5,000 miles on my Burley Samba tandem that I would know how to shift gears, but apparently I do not. I have bent the teeth on my chain rings several times and had to replace them three times now, at least once a year since we purchased the tandem. On our last long ride our chain got stuck when shifting into first on the chain ring and we were tossed off the tandem. This is getting very frustrating.

I am especially experiencing problems shifting when climbing hills and I am getting conflicting advice. For example, some people have told me to hesitate (that is, to let up pressure on the pedals) when dropping gears on a hill, others till me to never hesitate. Also, I have been told that I can shift to the first chain ring while on the fifth rear cog and others tell me that I should only do so when on the third rear cog. And just two days ago my wife was told that I should never shift when climbing hills but shift into the first chain ring at the bottom of the hill (which conflicts with the advice I have recieved from others). From our past experience, shifting too soon into a lower gear when climbing a hill deprives us of all momentum we build up when racing downhll in prepartion to attack the hill.

Would some kind person(s) out there please explain to me in simple terms how the hell to properly shift a tandem while climbing a hill.

I should add that we just switched the tandem over from twist-grip shifting to rapid fire. We have rapid fire on our singles and have never experienced any issues when climbing hills so I am hoping that rapid fire on the tandem will also be helpful. (If it stops raining today, we plan on hitting some local hills to test rapid fire out.) Also, less than 300 miles ago I had all the chain rings, cassette, and chain replaced, this seemed to have helped until last weekend.

Any advice or suggestions are welcome. Thanks.

[TandemGeek]

Shifting a tandem is best accomplished with finese... not brute force.

Downshifting: Shifting from the middle chain ring to the smallest / granny / alpine chain ring cannot be done with any reliability once you have the drive train loaded up, i.e., when you've found yourselves grinding out a climb at a cadence below 70 rpm. Therefore, you must anticipate the need to go into your smallest chain ring and make that shift while you are still carrying a moderate amount of momentum (70-80 rpm) before you've found yourself in your tallest (34t) rear cog and soft pedalling (just you) as you make the shift. If you fail to do this and still have some momentum you can sometimes accomplish a late shift by having your stoker soft pedal with you for just a moment while making the shift, i.e., telling your stoker to 'lighten up' will usually accomplish this but it should happen quickly. If the chain doesn't drop and you find your tandem's chain grinding away against the front derailleur as it tries to push the chain off the middle chain ring you're setting yourself up for a damaged drive train once the chain starts to come off the middle ring.

Upshifting: It's pretty much the same as downshifting; anticipate, shift while the revs are still moderate to high, and momentarily soft pedal (just you) as you make the shift.

Again, anytime that you find yourselve using brute force to shift the front or rear derailleur under heavy pedal loads and low revs is when you'll tear-up chain rings and cassette cogs. You'll definitely need to make sure your stoker understands just what you mean by soft pedalling when you call for them to "lighten up" as many stokers have only one mode on steep climbs and that's full-on pedal pressure on each down stroke.

[kevbo]

It seems to me you are paying too much attention to what people tell you. They may be spinners, and your team may be mashers. They may have a half-step geared road burner and you have a wide ranged tandem. You have collected a fair amount of evidence (in broken parts) as to what DOESN'T work so hot on YOUR bike, with your team....so whatever it was that you did just before things went to hell, don't do that anymore!

In all cases it is more stress on the components to shift while under load. Modern improvements (indexed shifting, ramped and pinned gears) allow under-load shifting, but it is still much easier on components to unload (hesitate) when shifting.

Rear deraillures act on the return (low tension) side of the chain, and modern ones usually shift well under load. Fronts are a whole 'nuther kettle of fish. They act on the tension side of the chain, and given enough load, it can be impossible to make them shift at all. The old rule was 12 teeth maximum between chain rings, but with ramps and pins, this can be extended a bit, and often is on tandems to get wide range gearing. Trying to force this to work under load is asking for the sort of trouble you have encountered.

So it is very import to unload (hesitate) when shifting the front, and less so for the back. On a tandem, it is VERY important to tell the stoker you are shifting the front, so he/she doesn't load the chain during the shift...they can also watch the chainrings and let you know when things are settled (though you should develop a feel for this). So I tell Susan "SHIFTING" and she relaxes her legs. I shift while turning the pedals (with no force) and she calls out "MIDDLE" or "GRANNY". Then when I am done shifting, I call out "PEDAL".

On the rear, I usually don't tell the stoker I'm shifting. I unload, but she keeps pedaling. For our team this means we shift the rear at ~40% load (stoker only).

Usually moving to a smaller chain ring works pretty well, as the chain "falls" rather than "climbs" onto the smaller gear. It should only take a 1/2 second or so to drop to the granny ring from the middle ring, or about 1 second from the big ring. (so I am assuming a triple front here). So you need to anticipate how much speed you will lose in that time, and shift the front a little before you "need" to. You should also have a good idea how much overlap you have between your chainring ranges....On our tandem this is 2+ gears, so when I drop one chainring, I usually also UPshift two gears on the RD at the same time....this puts us about "half" a gear lower than before the shift. Note I said "usually". I may upshift only one, or none depending on how late I left the shift, how steep the hill is, and how far we are from the top.

When approaching a hill, I want at least two, and better 4-5 lower gears available on the rear. If I have that, then I stay on the middle or big ring until I run out of most (or all) of those....the key is not to shift at any particular time, but to think ahead so you don't have to shift the front in a bad place, or after you have used up all your momentum. It is not so much science as art. Note what works and doesn't work for YOU and modify your technique accordingly. Pay no attention what I, or any "expert" says if it doesn't work!

So thats it for technique. Make sure your FD is well aligned and just high enough to miss the chainwheels. If you are using "plain" chainrings, upgrading to ramped and pinned large and middle rings will offer lots of improvement. As well, make sure you don't push the life of your chain too far. Running a worn out chain will cause trouble, and wear the sprockets so that they don't work well even with a fresh chain.....our tandem was in this state when we took ownership....new chain and chainrings set it right.

[zonatandem]

All good advice!
Anticipate your shifting a bit; don't wait 'til the last second like 'yipes, gotta shift NOW!
Have ridden all sort of tandems since 1975, and some do shift better/easier than others; however, you are in control of *when* to shift.
Yes, have lived/tandemed in Michigan and believe us, the terrain/need to shift is much greater out West!
In our 33+ years of tandeming, have never bent a chainring while shifting.
While you definitely know *how* to shift, you need to refine your technique a bit.
Pedal on TWOgether!
Rudy and Kay/zonatandem

[ROBERTSUNRUS]

:) Hi, I would have the front in the middle chain ring [if appropriate] and only shift the rear derailer while going up hill. Some of the front chain rings [sprockets] have too much differrence from top to middle. I had a bike with four front sprockets [not factory] and all were equally stepped in size; Makes for smoother shifting.

[dulongj]

I want to thank all of you for posting. My wife and I have carefully read over your comments and we believe the problem is that we are just pushing the bike too hard and shifting too late. I think the trick is to better anticipate the hill and shift sooner than I have been accustomed too.

We took the tandem out to a hilly area after I posted but before we read your comments. We went up and down the same hill three times and the chain popped off on the last climb. I brought the tandem in today and they confirmed that the 1st and middle rings are indeed bent. I am having them replaced and I have have confirmed that they are ramped and pinned (as were the chainrings that I just damaged). My goal now is to see if I can master patience, a light touch, and make these chainrings last a few years!

Thanks again for the tips.

[lhbernhardt]

All of the above are excellent suggestions. Two additional observations:

1. Buy and install one of those "chain keepers." This is a little curved piece of plastic that bolts to the seat tube at the level of the inside chainring. Its sole purpose is to keep the chain from falling off when shifting to the small inside chainring. It really works. You can do a HARD shift to the granny and be confident that the chain is not going to fall uselessly to the bottom bracket shell on the steepest part of the climb (leaving both of you spinning uselessly in place).

2. Shimano shifters suffer fom a really stupid design defect (among other things). When shifting fom a smaller cog or chaining to a larger one, things are fine; in fact, they probably shift smoother than a Campag in this direction. However, when shifting from a larger cog or ring to a smaller one, the shift doesn't occur until you release the lever. On a Campag shifter, the shift happens at the time you make the initial shift movement in both directions. On Shimano, there is a delay when going from larger to smaller, and this may be partially to blame for the timing problem you are having.

I notice that Shimano shifters are gradually improving, though. This year you can finally trim the front derailleur, and they finally got rid of the visible cable. About time! (Now there are only four things to fix before their design matches Campagnolo!)

L.

[mrfish]

+1 on the comments above.

Also get yourself some of those gear indicator widgets that fits into the cable - a quick scan as you see the climb approaching will allow you to see whether you have 1 lower cog left or 6, and therefore plan front chainring shifting, rather than running out of gears at the back.

[swc7916]

Shimano shifters suffer fom a really stupid design defect (among other things). When shifting fom a smaller cog or chaining to a larger one, things are fine; in fact, they probably shift smoother than a Campag in this direction. However, when shifting from a larger cog or ring to a smaller one, the shift doesn't occur until you release the lever. On a Campag shifter, the shift happens at the time you make the initial shift movement in both directions.

Unfortunately, the new Campagnolo Escape mechanism shifts on the release of the lever. You have to go Chorus or Record to get the old-style shifting.

[dulongj]

We tried one of those "chain keepers" and found it not to be helpful. If the chain did fall off the 1st chainring and the chain keeper did not do its job then the chain would really get mashed in there. I took it off. It is probably better to just make sure the derailleur is properly adjusted.

However, I have to agree that the Shimano front derailleur is slow when down shifting. It was slow when we had the twist grip shifter and it is slow with rapid fire. I am wondering if perhaps the derailleur might be a major part of the issue. We have had problems with shifting the chain rings from the first month that we owned the bike and have tried a number of different shifting styles (including most of the suggesting already made here but which I still appreciate as a refresher). However, it was not until your mention of the Shimano performance that I realized that it has been almost always when we are shifting from a bigger ring to a smaller one. I think I will talk with over with the mechanics on my next visit to the bike shop. Thanks.

[dulongj]

For the first time we took a long ride without any shifting problems. We did the Assenmacher 100 near Flint, MI, beautiful weather and a nice route. We made every hill with ease. Several cyclists warned us of the steep hills near the state park. We kept waiting for them and before we knew it we were at the state park and had accomplished the serious hills without even realizing it. The hills on this route were pretty mild compared to the Keweenaw. Nevertheless, we handled all of them well.

I credit two factors with our success: (1) the kind advice I received from all of you and especially the guidance to anticipate the hills better, and (2) the new rapid fire shifters we had installed. The front derailleur was still slow shifting from a high gear to a low gear, but we compensated for this by better anticipating the gear we should be in. Also, I am having a more rapid fire compatible front derailleur installed as I write this posting. Thanks again for all your help.

By the way, I would strongly recommend the Assnemacher 100 ride. The SAG stops were well spaced out, the route was scenic countryside, and most of the roads were nearly empty of traffic. The best part was that it did not rain like the other two centuries I rode so far this summer.

[kevbo]

1. Buy and install one of those "chain keepers." This is a little curved piece of plastic that bolts to the seat tube at the level of the inside chainring.

I think that's a fine idea, unfortuantly our Bilenky has a lateral tube that is perfectly positioned to prevent mounting such. One of these days I'll make a custom part. Just today we had the chain overshift...first time that has happened since I re-did the drivetrain.

[TandemGeek]

Just today we had the chain overshift...first time that has happened since I re-did the drivetrain.

Just curious, Shimano STI, Campy Ergo, or some type of bar-end shifting for the front derailleur?