JohnnyCool

We have a new Burly Rumba but these issues are putting quite a damper on our new found joy of tandeming. For the second time we have bent the inner chain ring of our Tracer 52-42-28 triple. Both times I shifted to the inner chainring and the chain jumped and became jammed. Either in the process of it getting jammed or my unjamming it, it bent. My LBS had not seen this happen before. Let alone twice. I know I can prevent this by installing a stop device but my concern is that the real issue is with the drivetrain. I had to keep loosening the the stop in order to get the bike to shift. It seems that by getting it loose enough I was causing the chain to jump. But when it was tighter it wouldn't shift. I thought I had it dialed in, when we wanted to down shift on the front, I would call "easy" and wifey and I would ease way up on the pedal pressure and it would shift pretty quickly. (NOTE: FD and shifters are Sora)

The chainline alignment does not look right to me. On the large chainring, I can use all 8 cogs in the rear (RD is a Deore) without any rubbing. On the middle, I get rubbing on the 6th cog! On my 1/2, I can use all the cogs of my Ultegra 10 spd when in the middle CR. I would think that would be the normal expectation. Is that unrealistic? On the small CR, it rubs on the 5th or 6th cog too. It seems like the FD is too far inboard compared to the the rear. One of the guys at the LBS didn't like the chainline either but the mechanic wants to just upgrade the chainrings. (Not sure how that will help the underlying cause) Any suggestions on what to do here?

Another issue they mentioned was the the 28t cog in the front should be changed to a 30t. I always thought 28t's were pretty standard on tandems. Will this change help the shifting?

On to the spokes...2 broken spokes in the past 3 rides. One front, one rear, both at the hub. Having never broken one before, is this unusual? We are a big team, 380+. Do we need to upgrade our wheelset?

Any input is appreciated.