Too big for bike seat, too small for a bike...?
 

Now that we're settled in our new house in an area with plenty of great cycling, my two boys (5 & 3) want to do bike rides with Daddy. I am contemplating seeking out a tandem bike like a used Burley Zydeco or Trek T900 for the very tall 5 year old to ride with me. My carpal tunnel'd right wrist should be able to handle an upright seating position for some amount of time, I hope. Another option would be to get a very upright sitting bike for me and a used trail-a-bike type for the 5 year old to ride. A Burley Piccolo would probably work with my recumbent.

The 3 year old is more of a challenge. Again, being big for his age (>90th percentile height) he won't fit in a seat on a bike. I wouldn't trust him on a trail-a-bike or as the stoker on a tandem since he's way too impulsive. Is my only option a $$$ bike trailer for him? If I could afford it I would pick up a Hase Trets which would be a great solution as it would work with my 'bent but alas those are out of the budget.

Even you do fit him to a bike position, most 3 year olds aren't ready for any kind of distance. You pretty much need a non-riding seat available for them where they can play, fall asleep etc. or have a quick bailout option.

If you can hook up a Piccolo to your bent, I'd do that. Then I'd get a very inexpensive trailer and hook it to the TAB. The 5&3 year old can share the TAB, with the 5 year old getting the majority of the time. If you don't have any more kids, the trailer will only be used for probably 2 more seasons, maybe slightly more or less.

Take a look at http://weehoogear.com/. They just came out and are super. I played with one at my bike shop and it is just wonderful. My little 2 year old was able to use it in the smallest position and I go peddle in the largest. It is really cool! I so want it.

That is pretty awesome. A recumbent TAB. I wish they would have the cost posted. No dealers near me. I see the suggested retail is $369. It would be nice if they had a geared option.

Weight limit is 60lbs and rider must be at least 38".

That's very cool. I will have to look into this more carefully. The Hase Trets is similar but is a 2-wheeler. I think pricewise a used Burley Piccolo and a used bike trailer are my cheapest options...unfortunately having just bought a fix-it-upper house our recreational dollars are a little tight right now.

Try a seatback for the TAB. I use one with my daughter.