We bought our first tandem in 1980 and started riding 90 degrees OOP. In 2006, we purchased a new tandem and decided to try riding IP. It was okay and we rode it that way for a few hundred miles. We switched to OOP and it seemed a lot better and hill climbing was easier. That is a qualitative evaluation.

We raced a district 40K TT championship in both IP and OOP and prefer OOP. It was not possible to determine any benefit of one versus another by our time since our fitness was different as well as the wind.

We have raced the Berkeley team trial three times and made the podium once in the tandem category. All three were done OOP with some high speed right hand turns that were not a problem.

With respect to standing, we prefer OOP to IP as it seems to be smoother.

Since my wife and I started racing individually, we have become like our racing friends with tandems - we race and train on our singles and use the tandem for special events and races. When considering inviting others to race on the tandem, IP makes more sense then to try to have a new person come up to speed on OOP.

IMO, IP is preferred for fast accelerations. We both race at the velodrome and my wife said the other day, it would be fun to race the tandem at the track. Well, it would be but... Anyway, I would only race IP at the track since coordinated power for the first couple of pedal strokes is very desirable especially when standing. That would also be true in crits and road races.

This year we are racing the Berkeley Team Time Trial on our TT bikes in the mixed couple division versus the tandem. It should be a lot of fun and totally different.