akexpress 

You have to give him credit that he sticks by his principles. I have had lots of spirited discussions with him and he is strong in his convictions. Him and Jan have built an incredible tandem tour company that sells out multiple trips a year most of which sell out in hours or days. Rumor has it that he is going to build moulded carbon tandems soon so he must have invested in a series of molds in different sizes.

merlinextraligh

Having done a Santana tour, I don't get that either.

But they're obviously successful, and I definitely believe we wouldn't have the number of performance tandem options we have, but for McCready and Santana.

twocicle

Bill's latest Santana Gen4 10" rotor has spawned heat dissipation gills reminiscent of Shimano's Freeza heat sinking, though the dimpling seems a weird idea. If I recall correctly, golf ball dimpling is intended to effect a static air buffer encompassing the surface area, vs. encouraging air movement over the surface to remove heat as does the Freeza "ruffles" design.

Photo courtesy of PrecisionTandems:


It would be nice to see this expanded to 8" (203mm) rotors too, as this might make for a good 6-bolt with a solid steel rotor that won't melt if abused (ie: Shimano RT86).

qspencer

OK, after some fun diversions about hub standards and Santana's design philosophy, I'm going to drag this thread back to the original subject: my custom tandem design. The drawings Waltly has been sending me show a solid front bottom bracket shell without any holes for bolts. The only other eccentric BB I have any experience with is my aluminum X-Peria tandem. That EBB is just a solid block of aluminum held in place by bolts that go through the bottom of the BB shell. I think I've also seen pictures of a split shell with pinch bolts to accomplish the same thing. However, in doing my research I've also see some eccentric bottom brackets (Bushnell, for example) that are completely self contained, i.e. they use their own internal bolt mechanism to press against the shell rather than relying on external forces. Is that correct? Is that preferred to the pinch bolt design?

geoffs

I know a couple of local guys that have road bikes made by Waltly that are a bit on the flexy side.
just make sure that if you have a problem with the frame not being stiff enough you can get your money back.

Paul J

Yes, most new tandem are using the solid bottom bracket shells. I'm not an expert but think this is a better design. Both our com-motion and Bushnell tandems has this design.

merlinextraligh

It does seem to be pretty universal in most modern higher end tandems.

Older tandems that rely on grub screws typically had an eccentric made from a solid piece of aluminum, which makes for a heavier design.

An expanding eccentric, with no screws through the BB shell can be made lighter.

See the Bushnell featherlight BB at 140 grams

ksisler

Merline - you are correct in that I was tossing a broken wheel your way. I have no idea how or why the Forum computers bounced it over to twocicle ... it could be something I did in error. Apologies to both of you as I was in a bad mood that day and the snark set me off. My foul mood (due to bill to repair my AC that was supposed to be under warrantee) made my post a bit too much.

I was really hoping to head off another long string of posts covering how much some folks despise Santana's and love their Kalfee or whatever. That nonsense had caused me to drop out of the forum for quite a while.

Now to square my position regarding Santana's; I never cared one way or the other about "the Bill Personality". I own a couple of their bikes, but I own many others also although mostly classics from the old days. I have never been able to justify the cost of some of the super bikes for sell these days and I admit I find most of the fat tubed frames unsightly, but it isn't a brand-name thing. Thus one of my favorite sayings from the old days still works for me: "To each his own said the maiden as she kissed the cow." Have a good day and do try to work in a 2bike ride with someone you care for.

merlinextraligh

No apology necessary, and my original post was a bit snarky.

And to clarify on Santana, I don't agree with the way they do several things, and I think the marketing has often been over the top. That doesn't mean that they don't make good bikes. They obviously work out well for a large number of people

ksisler

G; I have taken a strong liking to the Bushnell's for new builds as using them saves time and imho results in a stronger, cleaner looking solution. Where possible I use them also for replacing the eccentric's of existing old bikes when their guts fail one way or the other. When the oldies end up with seized internals or with the entire eccentric frozen in the frame from 40 years of owner neglect and corrosion...well that is another discussion thread altogether (and a situation that will put a guy in a bad mood!!).

qspencer

The Bushnell looks like a great solution. I ended up finding a much more economical Cannondale eccentric on eBay so I'm going to give that a try and see what I think.

ksisler

Be sure to give NOVA a look (in the sources thread) as they sell solutions from about $30 bucks up...and especially good for finding replacements for broken or fed-up-with originals.

ksisler

Hey, this thread caused a few very old and tired brain cells to rub together and spark;

Has anyone else built a tandem with an ECC at both bottom brackets? I did that about 30 years back for a family with a short, stubby wife and a tall daughter. The captain wanted to be able to use the ECC to move the rear crank up and down when one or the other stokers stepped over for a tour. I add a long slotted braze on mount for a modified rear changer to allow it to slide up and down as needed, found him a set of adapters for the crank arms, and added some spare cables to his kit. They road it for quite a while to my knowledge and always said they were happy with it... I guess this was more important that my initial thoughts on it (which were not so positive). Appreciate if anyone else has done this or has thinking on it.

B. Carfree

It wasn't built that way initially, but when our original custom tandem failed at the stoker bottom bracket/seat tube connection, the good folks at R+E in Seattle agreed to fix it. As they took a closer look, they realized that there was some rust that would complicate the repair. Their solution was to cut back the tubes and put in an oversize bottom bracket shell, then give me a second eccentric.