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  1. #1
    pan y agua merlinextraligh's Avatar
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    Ever eject a stoker?

    After 15,000 miles of riding a tandem, had a first happen this weekend: ejected my stoker off the back of the bike. We were doing power starts, a drill for developing power where you put the bike in the 53/11, and start out of the saddle from a standing start and go as hard as possible for 15 seconds. We've done these before without incident, on single bikes and the tandem. This time on the second or third stroke, we threw the chain on the back. When the chain came off, we're applying maximum force, and all the sudden no resistance. The combination of no resistance, my force pushing the cranks around, and the rear handlebars turning under the forces threw my stoker off the bike sideways (while I continued stokerless down the road for a few feet). Needless to say, we made quite sight in the middle of the intersection (we were starting out from a stoplight).

    The chain came off the big ring to the outside. I put the chain back on, checked that everything was adjusted correctly, (the limit scew for the front derailleur was fine)and we concluded it was just a freak occurence. So we tried it again. This time the chain came off to the inside, with no incident this time because we were prepared.

    Power starts are part of our normal base phase workout, and we've done them before on this bike ( A Burley Duet) without incindent. The only differnece is we've recently replaced the front chain rings. Other than this incident, they work fine.

    My only conclusion is that the big ring flexes too much to take the abnormal force put on the drivetrain by this drill. So we're not going to do power starts on the tandmen anymore. I'm not really expecting an answer here to this rather unusual problem, Just thought you guys might find this odd occurence interesting.
    And by the way my stoker, is fine albeit with alittle road rash, but a good sense of humor.

  2. #2
    hors category TandemGeek's Avatar
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    I reserve our "stupid tandem tricks" for our off-road activities. Off-road I have jettisoned Debbie from her saddle and onto my back whilst getting the tandem to endo on a very steep drop when the rear wheel "kicked" the tandem over. I've also dropped her off the back when we fell backwards into a creek that we had just crossed when the rear wheel lost traction and allowed the tandem to slide backwards before doing a reverse endo.

    Other, more traditional crashes have put her off to either side of the tandem, such as the crash we posted pictures of a few weeks back... which will apparently remain MIA until Joe Gardner apparently gets the BF server problems resolved. Hmmm. Wonder if linked photos still work? Here's one of Debbie's "little scrapes" from one of our biffs while riding Squirrel Gap at Pisgah last May.

    re: the Power Starts... are you guys training for time trials or just masochists?
    Last edited by TandemGeek; 12-04-05 at 08:33 PM.

  3. #3
    Senior Member Nachoman's Avatar
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    Wow, you guys are awesome! My stoker just sits around not pedaling!
    .
    .

    Two wheels good. Four wheels bad.

  4. #4
    Senior Member zonatandem's Avatar
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    Lessons learned???

  5. #5
    Long Distance Cyclist Machka's Avatar
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    I've been the ejected stoker!

    The last time I rode a tandem (Christmas Day 2002), my father was the captain, and I was the stoker. We got to the top of a hill after a difficult climb, he suggested we stop for a break, he unclipped with his left foot, because that is what he was used to doing ... I unclipped with my right foot, because that is what I was used to doing .......... and the resulting imbalance flung me off the back of the bicycle into the middle of the road.

  6. #6
    pan y agua merlinextraligh's Avatar
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    Quote Originally Posted by zonatandem
    Lessons learned???

    Not to do the powerstart drill on the tandem.

  7. #7
    Senior Member zonatandem's Avatar
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    If by 'ejection' we can include crashes, done a couple of those in our 30+ years as a tandem duo.
    Fastest was at 30+ mph descending a hill when chain dropped inexplicably (bounced due to a bump?) between small cog and dropout. *Instant* stop!
    Pilot did his instinctive paratrooper roll over the bars; stoker goes down with the tandem.
    Damage: Pretzled front wheel due to instant stop; stoker roadrash head to ankle, including a black eye; captain huge hip hemotoma.
    Four days later we were doing a pre-planned 200-mile 3-day loop ride by the Grand Canyon with a new front rim.

  8. #8
    Senior Member
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    Exactly why would this be valuable from a standing start? Especially with no use of gears. Why not on-the-fly, as in interval sprints, or perhaps hill repeats?

  9. #9
    Long-time Curmudgeon DrPete's Avatar
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    Yeah, that seems like it would be a lot like trying to start a car from a dead stop in 5th gear.

    At least in a car you'd only trash the clutch--much easier to replace than knees.

    DrPete

  10. #10
    Senior Member zonatandem's Avatar
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    A faster (seated) start is much easier when pedaling 90 degrees out of phase . . . and no broken chains, no ejected stoker.

  11. #11
    Banned. galen_52657's Avatar
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    Who ever came up with that type of exercise? (taking off from a standstill in top gear). Sounds not-to-bright to me.

    If you want a high-resistance workout try the weight room people.....

  12. #12
    pan y agua merlinextraligh's Avatar
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    Quote Originally Posted by galen_52657
    Who ever came up with that type of exercise? (taking off from a standstill in top gear). Sounds not-to-bright to me.

    If you want a high-resistance workout try the weight room people.....
    It's a standard part of the Carmichael Training System program. It is essentially resistence training, but on the bike, so more sports specific than weight lifting. You're working the same muscles as doing squats in the gym.

    As for why not do intervals or start at a faster speed, It's a different workout than doing intervals, because it's not cardiovascular, its not intended to raise your HR or tax your aerobic system its designed to build muscle power. If you did the drill at a faster starting speed you wouldn't get the same effect because the resistence would be too low.

    As for who came up with it, Chris Carmichael and Lance Armstrong can't really take credit for it. If you go back in time Lemond reccomends the same drill on an incline in his books, And Eddy B also had a similar drill. They just didn't call them power starts.

    It's an intense exercise and you don't want to do it without some base, but it's effective.

    And to think I pay $149 a month for these drills.

  13. #13
    Banned. galen_52657's Avatar
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    Quote Originally Posted by merlinextraligh
    It's a standard part of the Carmichael Training System program. It is essentially resistence training, but on the bike, so more sports specific than weight lifting. You're working the same muscles as doing squats in the gym.


    And to think I pay $149 a month for these drills.
    I have been racing bicycles for 20 years. I have never heard of anybody doing sprints from a dead stop in their biggest gear. Going up a steep hill in the biggest gear? Yes.

    But if it is a prescribed workout, did you ask Carmichael if you should try it on a tandem???????


    I think they saw you coming....

  14. #14
    Time for a change. stapfam's Avatar
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    Never been ejected as a stoker, but that is only due to the SPD's being very tight. In my early days of Tandemming, I had the spd's loose and often lost the pedal on bumps. At the faster speed we go at now, the feet do not come out of the tight spd' s but occasionally feel like getting off when it gets hairy.
    How long was I in the army? Five foot seven.


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  15. #15
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    Quote Originally Posted by merlinextraligh
    The only differnece is we've recently replaced the front chain rings. Other than this incident, they work fine.
    What happens with a worn chain and a new chainring? Can that cause the chain to lift off of the gear?

    -Greg

  16. #16
    Senior Member
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    Well, the Carmichael training system is surely not designed for a tandem. You want to build that kind of low-end torque, go tackle the large hills around your house in the Big Ring. Off the saddle. Repeats. I got to 13 world championships and none of the folks who made the podium were doing this sort of "canned" program. The rookies were. You need to put in some time researching basic training mathods, utilize them in your own life, see which work, then develop a strategy based upon that data. Nobody is going to be very helpful. I've used coaches who were world pro champs, world amateur champs, IronMan champs, coached in the Olympics, etc... (my fiancee was coach of the year in New Jersey twice). You got to do this on your own. For teh reasons clearly exhibited here: the methods have to fit you. This method does not fit.

  17. #17
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    I had a rather serious stoker ejection in October at the Bloomington, IN Hilly One Hundred. We had our tandem all of 2 weeks. We had a wonderful day riding through the hills of southern Indiana on a rare 70 degree Oct. day. We had a ball frequently hitting the low 40 mph mark on the downhills (I am a longtime motorcycle rider and it felt very comfortable and natural). My wife was egging me on wanting to go as fast as possible. We did the 50 mile course that day and it was so much fun. That night, we were coming back from the showers when it happened. There was a hole beside the sidewalk that couldn't be seen due to the nice level grass. Our front wheel got caught and it threw us sideways down onto the sidewalk. My wife's leg got caught between the bike and the edge of the sidewalk. When she lifted her leg, the foot just dangled to the side. Both bones were broken clear through. She now has a steel rod down her tibia and the cast just came off today. On the plus side, she is looking forward to next year's Hilly and getting her leg back into shape. Her only condition is she wants to get rid of our recumbent tandem and get a 3 wheeled recumbent tandem! What a woman!

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