Tandems & Power

As we started riding tandem we begun to use some of the same training techniques that we used on our single bicycles. At the time we looked for a power meter that we could use to train with, but found none that would work for us on the tandem, so we started to monitor our heart rates and used heart rate zones to train, a problem with this approach was that in a tandem the captain and the stoker are in the same bike and connected by the timing chain so it was very hard know if one of us was doing more work or to much work, the problem is that the rider that is doing more work would end up getting tired and would reach and go over LT sooner, specially in fast of hard workout sessions, and once one of us reached this stage the other would have to take over the slack and eventually we would both reach total meltdown!

Training with Heart Rate

Training with out heart rate wasn’t ideal as I we could be doing a recovery ride but my stoker wasn’t recovering at all or vice versa. Our answer to this issue was to use the knowledge we had of training with heart rates on our single bikes, we knew that our threshold was almost identical, the only difference was that I would be going faster with the same heart rate numbers, the first step was to find out at any given speed and riding in different situations what were our hear rates, by doing so we found that our stoker being a female and while riding on my wheel on a climb or side by side on normal situations was always about ten counts higher in order to stay with me. Now that we had this data we started to apply it to our training on the tandem. While riding I started asking my stoker her heart rate and if it was higher than mine she would ease on the pedals and I would take the extra work needed to maintain the speed, by doing so she eventually  would be riding at about the same counts or just bellow mine. This allowed us to gauge and understand our heat rates versus the effort or perceived exertion, and after some time we could get in sync quite easy. This made the tandem quite more efficient and faster as were not dying like before we started using this method.

The iBike Power Meter

Training with heart rate zones is good and inexpensive but is somewhat inaccurate and has some variability as there is several factors that can affect heart rate, conditions like temperature and other factors witch I will not go into detail. Somewhere I read about iBike, a power meter that used a different a way of measuring and didn’t need any special hubs or cranks, the system used wind speed, till and other data to calculate power. I was very intrigued as this could be the answer to our tandem power dilemma. I purchased couple of iBikes and got to work. I installed and calibrated the  iBike computer just as you would do on a single bike, I also did a calibration on our single bikes as iBike allowed us to be used in different bicycles by just uploading the correct calibration file for the bike in use. Once calibrated we started using it, I was amazed as the data was very good, and it seemed to really represent our combined power numbers, we had power data from before and this allowed us to compare and realized that we would be able to train with power on our tandem!

The Power Numbers

In order to train with power on the tandem we had to find out our combined FTP on the tandem, this was not as simple as just adding our FTP numbers from our single bikes, a tandem requires two riders to works as team, just like in a team time trial but also added different factors the equation, and really changed the riding dynamics compared to a single bike, some of the differences are gear combinations, overall weight, cadence and differences on riding stiles among other factors. This being said wee needed to find our power numbers for the tandem; we did the usual power tests as you would do on a single bicycle, tests like FTP and all the other tests that were needed in order to correctly start training with power.

The Garmin Connection

All of this was great but we still had a drawback, the stocker needed to also see power in order to administer her output. At this point we could train with heart rate quite efficiently, and each of us had a good idea of the perceived exertion and good feel for the amount of power to the pedals with any given heart rate. We were using Garmin Edge on our bikes and the tandem for obvious reasons, the captain and the stoker could have speed, heart rate as well as they could be used on our single bikes also. Once iBike came with the option of transmitting to the Garmin Edge 705 our last piece of the puzzle was in place. Now the stoker could see real-time what our combined power was. Since then we have being able to monitor, train and race our tandem with power just like on our single bikes. The ability to train and race using power has brought riding our tandem to a different level.

Data from The Stagecoach 100 Mile Time Trial.

Bellow you can see data recorded during the Stagecoach Time Trail century. This being our first TTT of the year we rode it well bellow our FTP, this way we could ride the whole 100 miles at a safe pace and maximize our time with out dying prematurely.  The conditions were very good we had some head wind for most of the ride but overall it was good.

If you are interested on getting a tandem or getting some coaching please let us know.

About the author of this article.

Alex Estrada a cyclist since the 1980s. He raced professionally both mountain and road and winning two mountain bike championships abroad. Now a bicycle store owner and a USA cycling coach.