LongVehicle

Still more questions, the first being about brakes. I am running V-brakes with travel agents and STI 6770 levers. Which would give better braking performance, V-brakes and travel agents or the BR6700 road brakes? Has anyone figured out, or is running, a hydraulic road option? Shimano's new road hydros won't be tandem approved, many systems seem to be "closed systems" so lengthing the lines to the rear is out of the question. What about mechanical disc? My frame does not have a disc mount on the rear (swapping in a disc-ready fork isn't an issue), but has anyone used an adapter like ones I've seen available from Busettii (and others)? What are the thoughts/drawbacks of an adapter? Anyone tried splicing together hydro discs with road levers? I think TRP has a mechanical to hydraulic adapter, but I haven't read many great reviews on it and again I think it is a closed system. Magura never seems to answer questions on the issue.

Question 2: Frame weights. I'm looking at a couple of tandem frame builders (can't quite justify the CalFee or Paketta I drool over often), and I'm having a hard time finding advertised "frame only" weights. I'm not looking for a sub-25pound complete build, but I would like to put my next frame on a diet over my current 2000 technology affordable frame. What is a reasonable, (good???) frame weight to shoot for?

Team Fab

https://www.bikeforums.net/showthread...ke-bee-s-knees that should give you more than enough on brakes.

Reasonable price light tandem and new = Cannondale

Dean V

I would go for good double pivot caliper brakes. eg. Ultegra or Dura Ace.

waynesulak

When thinking about a conventional steel and aluminum tandem frames, a general estimate for me is that aluminum saves roughly 2.5 - 3 lbs on a medium frame compared to top level steel. Be aware that some budget steel bikes even by good builders like Comotion use heavier tubing than the same companies top level steel tandems. Best weight saving is on a fork. A carbon fork can save 1 - 1.5 pounds compared to a steel fork.

The personal choice is comparing the weight and factoring in how you like the ride and performance of various aluminum and steel bikes. Other factors can trump weight as shown by the sale of coupled tandems. Couplers add quite a bit of weight but some would not have a tandem without them.

I believe that you are thinking along the right track by comparing frame weight rather than tandem weights. A Calfee can have the same components as a steel Comotion on both the high and low end. There have been some pretty light aluminum bikes posted here over the years using light components.

My 2000 medium stock Santana Arriva bare frame weighted 11 lbs (on a bathroom scale so only an estimate) This is a mid level frame. Santana has a lighter model steel frame.

Can anyone withe a aluminum tandem contribute their frame only weight? My guess is 8 lbs for a bike with a 56cm or so captains top tube.

jnbrown

Not sure about this but I think our old Santana Sovereign frame weighed about 7.5 lbs.
The fork was a boat anchor. but the whole bike was around 36 lbs. I see a lot of used ones around so that might a good option, but you would have to upgrade a lot of parts to get the weight down and make it more functional.
It had V-brakes which I hated and constantly squealed and were grabby.
I think our Calfee is closer 6 lbs, I went with Mavic SSC brakes because I heard they were more powerful than Shimano.
They do feel really solid, but I don't see anyone selling them anymore, otherwise I would go with Ultegra or DA brakes.

DubT

Our Calfee Tetra Small/small weighs 7.017 pounds, this includes the frame, the fork, Chris King headset and the Bushnell eccentric.

waynesulak

I see from Longbike's previous post that the team currently rides a Burly. I think that it is more the tubing on that frame rather than the age that is the issue. A high quality frame of the same vintage from Santana or Comotion would for me be a large increase in performance. Even when new Burlys were budget tandems with rather thick walled tubing compared to bikes like an Arriva or Speedster made with 8/5/8 tubing. The Burly tubing is much heavier and less lively. Regardless of the era, there is a big difference between a dependable heavy steel bike and a performance steel bike made with thin walled tubing.

Chris_W

I've run V-brakes with 6700-series levers and no travel agents on our tandem and a couple of single bikes. I eventually got tires of having to fiddle with the spring balance too frequently and keeping the rims very true; the braking feel and power was fine, but after quite some time I decided that I didn't like the tight clearances between rim and pads. I've since switched some of these brakes to discs and some I've added travel agents too, both of which have resulted in as good or better braking and less need to fiddle.

I've also briefly used 6700 levers with older (6600) calipers on a single bike, and I'd definitely not recommend that - certainly less power. With the 6700 calipers that setup works OK, although not as good as on my other single bike that has front and rear cable discs (Shimano CX77) with 6700-series levers. I didn't think there was much difference in the braking between the discs and calipers until I'd been riding only the disc brake bike for the last couple of months, then when I got back on the rim brake bike I noticed that I had to change my style significantly due to the reduced power, modulation, and smoothness that I'd got used to with discs. I won't touch the hydraulic stuff because I hate dealing with the maintenance headaches (a simple job like changing brake pads can turn into a half-hour nightmare involving wrestling with pistons - no thank you, I'll take mechanical discs every day).

jfarwell

I just switched over my single bike from mountain bike bars to road bars. I have old 6500 ultegra levers from one of our tandems installed. The brakes work, but the tolerences are pretty slim, and I may add travel agents. Is there any chance you can post a photo or describe the set-up for the travel agents and the disk brake caliper. Thanks

Chris_W

6500 levers definitely will NOT work with V-brakes. The cable pull ratio is all wrong; it was changed on the 6700 series (plus 7900, 5700, and more recent) to be in between the standard road brake ratio and the V-brake ratio, which is why V-brakes mostly work with those levers; but with 6500 you're asking for trouble. There should be lots of info around the web about how to install travel agents. There are also several cable disc brakes that are designed for road levers, including Shimano BR517, CX77, Avid BB5-R and BB7-R (there is also a MTB version of both Avids which would not work with your levers), so if you have a frame and hubs that can take discs, then that is a good option.

mje

jfarwell

thanks for the insight. Think I'll switch over to proper brake levers and bar end shifters. Best regards.

B. Carfree

I didn't see the frame weight, but Rodriguez sells some 26 pound complete tandems. https://www.rodbikes.com/images/galle...light%20tandem
I'm sure they would give you the frame weight and they are sticklers for truth-in-weighing. If you want the frame to weigh in under some value, they will either tell you they can't do it or they will guarantee the finished weight. Same deal for the final build.

If you want to trim that one to two pounds from the fork that carbon forks can do, you may get some arguments from Dan Towle, the owner. He's not big on using any component that isn't explicitly rated for tandems.

LongVehicle

Affirmative, and this build wasn't a weight-weeny build. Purchased at the time not for its performance but the fit. It tips the bathroom scale around "COUGH 44 COUGH pounds COUGH." I think even the bar tape is "hefty."

waynesulak

Everyone talking about bikes has the tendency to use low weight as a proxy for high performance. I know I do it sometimes. Actually while low weight is easy to measure and discuss it is not the same as high performance. For example, aero equipment can often be heavier than non aero equipment. Likewise I believe that the lightest frame is not always the fastest. Things like good handling, good brakes for the application (disks are heavier), tires and wheels you can trust, and even rider comfort can all can help riders go faster.

LongVehicle

All true and being considered in my search for a new frame. Years ago I had teh "pleasure" of riding some light-weight bikes that were about as stiff as cooked spaghetti. I also don't have the need to go sub-26, but there are definitely some stiffer yet lighter frames than the boat anchor we're currently dragging up the hills.

DubT

We went from a 40 pound bike to a 26 pound bike and we perceived a significant difference in the climbs that we do here in the Midwest. There is one particular climb that we actually had to use granny for that we now climb in the big ring. However adding HED 3 Tri-spoke "Aero" wheels made a big difference in flat land speed, especially with a cross wind. I am a STRONG proponent of aero and light weight. However from what I am reading aero normally trumps lightweight. My Trek 9.9 is designed to be extremely aero and it is probably the fastest single that I have ever ridden. The Zipp 3000 was also fast but i have not owned it for several years so do not have a direct comparison.