I purchased a tandem bike for my family, a co-motion periscope. We tend to ride in the evenings and have been caught out late sometimes so I'd like to put some "to see with" lighting on it. I have a 700c dyno wheel built up with a SON hub with 36 spokes and a mavic open pro rim, and I'm considering its suitability on a tandem. The stoker will alternate between 7 year old and 10 year old, 50 - 70 lbs. I had the wheel built when I was 30 lbs heavier, so I was thinking total weight may still be in the "okay" range for the wheel. I'll be running 700/28 tires. What I can't figure out is the split on the math for single bike vs tandem. Will the tandem put a lot more weight on the wheel than my 30 lbs heavier self did on a solo bike?
My instinct is telling me this is probably not a good idea, but I need help with the numbers to substantiate the cost of a new rim/spokes and a wheel build. I have an IQ fly light and taillight, so its really a comparison between new light, a wheel build, or go with what I have and maybe worry about wheel integrity.