Tandem Cycling - da Vinci triple crankset & BB tech questions

I'm currently in the process of replacing our old Campy Record triple crankset (54/44/36) in favor of a da Vinci (52/39/30) due to the fact that our aging years are catching up to us. However, when I attempted to put on the new da Vinci set, I've noticed that our current spindle is far too long by perhaps 10mm to 15mm if not more. The BB shell is a standard 68mm, but I'm wondering if there are any others here who might be using essentially the same da Vinci set and if you'd happen to know what length of a spindle to use? As it is now, the front derailleur is unable to reach the middle and outer chainrings. Also, our current BB is a Phil Wood model from the 80s, so will I need to purchase a completely new BB and spindle? Since I haven't had much experience in the BB area, I'd appreciate any help. Thanks in advance!

Edit note: I might also add that da Vinci recommends a spindle range of 107mm to 113mm for the stoker, so I'm thinking that a 110mm might be about right. I do know, though, that without taking the crank back off the bike that the current spindle must be about 130mm or longer. It's quite a significant difference, to say the least. Thanks again!

Jim

I'd give DV a call. (The number is on their website). They are super nice and happy to help and seem to be endearingly geeky engineering types. Todd does not always respond quickly to email, so call.

I'd give DV a call. (The number is on their website). They are super nice and happy to help and seem to be endearingly geeky engineering types. Todd does not always respond quickly to email, so call.

Thanks, Scott! I called DV, and they basically said that the length of the spindle would be determined by how much our chain stays flare out, for some will protrude outward more than others. In a nutshell, though, I've determined that I'll have to get something in the range of 103mm to 113mm, but my current BB setup will have to go. The bike builder is the guy I need to speak with, and he just happens to be on vacation at the moment. But, thanks again!

BTW - "endearingly geeky" is a great term! I like that!

You need to get new BBs because the da Vinci cranks require a different taper (JIS) than the Campy cranks. We use 113 front and back but could have gone narrower. 108 probably would have worked. What make tandem do you have?

I'm currently in the process of replacing our old Campy Record triple crankset (54/44/36) in favor of a da Vinci (52/39/30) due to the fact that our aging years are catching up to us.

How come you have to switch out the entire crankset, couldn't you just get the chainrings in the size you want (http://www.peterwhitecycles.com/chainrings.asp) to fit on the Campy triple?

How come you have to switch out the entire crankset, couldn't you just get the chainrings in the size you want (http://www.peterwhitecycles.com/chainrings.asp) to fit on the Campy triple?

Really old Campy stuff came with a 144mm outer BCD, making the minimum middle ring size 41 teeth. I don't know about the inner, but to have 36 teeth on it, maybe it was a 110mm BCD?

You need to get new BBs because the da Vinci cranks require a different taper (JIS) than the Campy cranks. We use 113 front and back but could have gone narrower. 108 probably would have worked. What make tandem do you have?

The bike is actually a new tandem built by Bob Brown Cycles out of St. Paul, MN, and the Campy crankset (28 yrs. old) is one that we thought we'd transfer over to the new bike. With some further consideration, though, we thought we'd go with some easier gearing. Upon briefly speaking with Bob yesterday, he recommended that we go with the Phil 108mm, so I plan on ordering one today. I'm sure it'll make a huge difference. And, thanks for all the feedback. It's greatly appreciated!

Regarding the questions of others about chainring replacement on the Campy set, Chris hit is right on when he spoke of the old Campy BCD. The smallest possible chainring set for that crank is a 52/41/36, although, I've heard that smaller inner rings are around, but extremely rare.

Thanks again everyone!