Is the independent coasting system really worth the additional costs?
Merlin addressed part of that. Teams that have it say they love it and daVinci only claims one customer has ever come back to request the independent coasting / variable phasing feature be locked out. Kinda your call there partner.
Are the components used in the Joint Venture significantly different from the entry level Grand Junction to justify the additional costs?
Only if you can tell and appreciate the difference in the reduced weight and/or finish quality of those parts. Seriously, the biggest difference is the actual cost basis of the components and frame that daVinici must use to set its retail price. They are very up front when it comes to the frame, citing from their Website: "da Vinci Designs has finally partnered with the best steel frame fabricator in Taiwan and made the commitment to a production run, so we can bring you a more affordable tandem with all the benefits of the ICS drivetrain. The Grand Junction also uses the same high quality Reynolds tubing used in our Denver-built tandems. If you've been looking at a da Vinci tandem, but the price has held you back, the Grand Junction is the bike for you."
Having seen a Grand Junction up close and personal, I can say without hesitation that the quality is really exceptional. Of course, it got that way because Todd & Brian spent an inordinate amount of time on site at their fabricator's facility in Taiwan working with them to get that level of fit and finish for their frames. However, when you buy a Joint Venture you're getting something that is more close to a custom frame as it's hand-made to order in Colorado by the folks at daVinci. Component value is what it is. The more expensive components are in most cases simply made lighter using more expensive materials and look better due to added finishing steps or, again, more expensive materials and processes. Beyond that, performance of these components will have more to do with their adjustment, the operator's technique and the engines than anything else.
What is your opinion of the S&S Couplers and travel case versus just using just acquiring an elongated Bike Pro USA Tandem Case for transportation?
The added value of S&S couplers has been greatly diminished over the past 7 years as air carriers have reduced weight limits and added fees for luggage that previouly was checked for free. So, if you're looking to recoup your investment in couplers on baggage fees just know that it would take a heck of a lot of travel to do that given the added cost of the couplers and cases. You can do the math, just divide the $2,400 cost premium of couplers and cases by what you think you'd have to pay for travellling with two large checked pieces of luggage vs. the current excess baggage fees for oversized containers / bikes. In otherwords, if you assume it would cost $100 per leg of a journey, you'd have to take 12 round trip flights to amortize that cost.
However, and unless you plan to ride your tandem to and from your points of departure as one intrepid traveler we know does, what an S&S tandem still affords a traveller is far more flexibility and ease in their travel plans and with ground transportation to, from and in between points of departure. After all, a full-size tandem boxed for travel is a behemoth that requires a large vehicle and/or roof portage. Not all shuttle buses are large enough to accommodate them and never mind a taxi or average size rental car being large enough. So, if nothing else, S&S tandems continue to offer travelers ease of travel with their tandem via any mode of transportation. And, if someone throws out the B.S. argument regarding the cases being an issue, remember that there's nothing that prevents someone from packing an S&S tandem in disposal, reinforced cardboard boxes, e.g., bike boxes provided by airlines work just fine too.
And lastly, what are the pros and cons of 26 inch versus 700c wheels?
daVinci actually covers it in a very nice and succinct way on their Website:
Why 26" Wheels for the Road?
da Vinci Designs tandems are built to use 26” wheels for three reasons:
- 26” wheels are stronger than 700c wheels. Since tandems carry more weight than single bikes, they are ideal for running 26” wheels.
- 26” wheels have less inertia and weigh less than a comparably designed 700c wheel. Therefore, they accelerate more quickly, climb better and are fast.
- 26” wheels offer a versatile tire selection, from narrow road tires to aggressive mountain bike tires.
If you're looking for a lot more techno-babble on the subject, Bill McCready of Santana Tandems, Inc. wrote a very detailed piece back in the mid-90's that you can find here: http://www.gtgtandems.com/tech/700-26.html
In general, it's my belief 26" wheels are a better all around wheel than 700c "racing wheels". However, 700c have pretty much become the defacto wheel size for most road-going bikes and debating the pros and cons isn't really worth the effort any more than Campy vs. Shimano, In-Phase vs. Out, etc. The latter is particularly true nowadays as wheels are stronger and lighter than they once were, road-specific 26" tire selection in the US is a mere shadow of what it once was, and I suspect even in Europe 700c tires, tubes, and wheel components are fairly common in most places.
Personally, if you can look past the 'image' issues that equate 700c wheels to lightweight racing bicycles and the status quo, 26" wheels make a lot of sense in much the same way many average cyclists are discovering "compact drive" (i.e., 50t x 36t and 48t x 34t chainring combos on 110mm cranks) are more practical than the ubiquitous 53t x 42t OEM set-ups that came on their road bikes.
The only real downside to 26" wheels if perhaps finding high-quality super-narrow 26" road racing tires and tubes if that's what you're committed to using. While the wider 26" touring tires are always availble, those narrow racing jobs require that plan ahead and be prepared to be fully self-sufficient by carrying sufficient spare tubes or patches and at least one spare tire as most shops nor your fellow riders will have anything like that. Moreover, when touring it would make sense to not only have an extra tire on your tandem but to also keep one or two more in your luggage "just in case".