Tandem Cycling - Water in the hole

Last Saturday we rode the last 55 miles of a 65 mile ride in an all out downpour. This Saturday I got around to cleaning up the bike (Trek T200) and decided it was time for a new transfer chain. When I loosened the eccentric bottom bracket I was amazed to see about a half a cup of water come running out. The water was clear, not rusty, so I'm sure it just came in during last week's ride. I have no idea how it got into the tubes.

Has anyone else had this happen? If we had ridden after the rain stopped would the water have worked itself out? Will I have to "drain" the eccentric every time we ride in the rain (what a pain), or is there a better way to get the water out?

Thanks,

Yes, it happens to all of our tandems (although you'd need to quantify 1/2 a cup -- 1/2 of what type of cup?) and, yes, it's an annoyance.

As to where the water gets in, IMHO I believe it sneaks in from a variety of places. On the road tandems, most likely sources for our water penetration has been:

1. Front eccentric -- being fed by the rooster tail coming off the front tire, I suspect some water seeps in between the eccentric and the bottom bracket shell, and then works it way into the boom tube.

2. Rear BB -- pulled into BB shell between the axle and seals by capillary action as the axle flexes under the extra load from the front cranks and then, like the front end, the water moves into the boom tube.

3. Rear chain stay openings -- those little holes near the rear drop outs. Water can get in there, move forward to the rear BB and then move into the Boom tube.

Water gets into many of the same places on single bikes, but they don't have that boom tube to act as a reservoir and the water usually runs back out.

Originally posted by blwyn
Last Saturday we rode the last 55 miles of a 65 mile ride in an all out downpour. This Saturday I got around to cleaning up the bike (Trek T200) and decided it was time for a new transfer chain. When I loosened the eccentric bottom bracket I was amazed to see about a half a cup of water come running out. The water was clear, not rusty, so I'm sure it just came in during last week's ride. I have no idea how it got into the tubes.

Has anyone else had this happen? If we had ridden after the rain stopped would the water have worked itself out? Will I have to "drain" the eccentric every time we ride in the rain (what a pain), or is there a better way to get the water out?

Thanks,
Blwyn,

We were there with you and experienced the same rain. Better check your head set as well. Ours was feeling a little different when I set about cleaning the tandem. Took it apart and got a bunch of water out of it.

I hadn't considered the bottom brackets. I better run out there and check them as well.

Saturday was a pretty good day for us. Unlike you we had no problems. We definitly stayed cool! We're off to RAGBRAI in a couple of days. Hope it's cooler than the Wisconsin ride was. I won't hold my breath tho. :D

Thanks for the information Mark. I guess I'll be checking the bracket after rainy rides in the future. Do you happen to know a good source of the longer bolts for taping my wedge type eccentric loose? None of the local bike or hardware stores seem to carry anything.

Gus you were right. There was water in the headset too. Of course I found the nuts on the headset were larger (40mm) than any wrench I have (tells you how much maintainence I've done on them). Had to borrow a huge adjustable wrench from the neighbor along with my pipewrench- not a good long term solution. Why does simple maintenance on every bike require another tool that I don't have. It's got to be a conspiracy by Park Tools!

Check with http://www.LooseScrews.com or check your Yellow Pages for a commercial screw/bolt/machine shop wholesaler. I'm fortunate to have "Threads of the South" nearby and can usually find every size of stainless steel metric or SAE bolt, nut, washer that I need for bicycles at wholesale prices, e.g., high-grade stainless steel water bottle bolts for .08/ea.

My aluminium frame picks ups a bit of water every time it rains.

I just tip my bike up and the water flows out of a couple of holes near the rear dropouts.