DeadGrandpa

I'm not an mtb guy, but my lady friend is afraid of riding on paved roads, because of, you know, cars. We have taken my mid-80's vintage Santana Arriva on a local MUP greenway, and she said she liked it. Looking forward to more. I hate MUP's. I'm looking for forest service roads in state and national forest type places, but I have seen serious ruts, washboard, football sized rocks bulging up randomly, and generally uncivilized riding surfaces for my road tandem. If I buy another tandem, I would like to go lighter, with wider tires, and able to go anywhere offroad on an American built machine. Suspension or not, to be determined.

And yes, I know that several tandem manufacturers offer carbon frames, but are they robust enough to hold up? I don't see boulder or stump jumping in our future, and no downhill bombing runs. We're too old for broken bones.

I have read several threads here, and aluminum is the natural next step: Fandango from MTBtandems, but for their weight. I like the light weight of the Calfee products, but are they strong enough?

CliffordK

Sorry, no direct experience with Calfee bikes, or CF MTBs.

The Calfee tandems look sturdy with a lot of oversized tubing, although I'm surprised there are no rear diagonals.



I'd try to get a little better warranty commitment from them. While I wouldn't expect crashing a bike rack into a garage to be covered, I would expect a realization that a MTB would be designed to take a certain amount of abuse (even if you are planning to ride on gravel roads).

Those look EXPENSIVE.

Another option to look at is Titanium.

For road tandems, I think there have been a few people who imported Titanium tandems from Asia. I don't know about MTB based tandems. I did see one FAT tandem on Alibaba.

CliffordK

Here is an Alibaba Titanium MTB Tandem, and Titanium Coupled MTB Tandem.

https://www.alibaba.com/product-deta...474798623.html
https://www.alibaba.com/product-deta...481451945.html

I hope their posted weights are incorrect. But the cost is less than half of the Calfee prices.

DeadGrandpa

Thanks, CliffordK. I have made the decision to buy American built bikes from here on out. I may have to "settle" for titanium, but was hoping to get testimonials from carbon mtb owners about durability before making that decision. Carbon frames are lighter than titanium.

Yes, the Calfee machines are expensive, but if a 30 pound carbon tandem can survive gravel roads and other non paved adventures, it would be worth it to me. Btw, if an MTB couldn't handle the pounding of gravel roads, for what kind of riding/routes would it be intended? Cowpaths?

A FAT tandem could be an acceptable solution, but I haven't seen carbon frames with clearance to accommodate tires that wide. I anticipate travelling, so lighter weight AND the ability to de-couple/pack into travel cases are desirable. Calfee's lack of diagonals enables use of SS couplers, as well as saving weight and build labor. The larger tubing allegedly compensates for the missing diagonals.

DCwom

That's funny because my wife doesn't want to ride on MTB trails, because of, you know, trees. We ride an aluminum frame with no-suspension (32 mm tires) on unpaved rail-trails and I can say that any surface less than stone-dust can be a rough ride with the stiff aluminum.

twocicle

If concerned with damaging a frame, I would look for one that can be easily repaired. Aluminum cannot. The carbon tubing Calfee uses for the Tetra is very tough. You'll see that used on most frames where the ultimate durability is sought.

FWIW, we have had Calfee do a couple frame modifications and so we became somewhat familiar with what they can do to pull apart an existing frame and redo sections if desired. Quite amazing.

Here is a pic to one Calfee/Ellsworth being hucked and they apparently have no issue doing so...




There are plenty more photos of this bike (and riders) half way down the event article here...
https://www.pinkbike.com/news/2014-b...hoto-epic.html

Just tell your stoker to clip in and hang on tight, or else ...

DeadGrandpa

That is funny. I'm running 27x1+1/4 tires on my Santana (yes, it's that old) and it handles the manicured gravel on the MUP much better than I expected. If I only wanted to ride city paths and rail trails, I wouldn't need an MTB type tandem, though wider tires would still be nice. I'm not opposed to front or full suspension. I have never been riding farther afield than Dupont State Forest (NC) and the Denali hiway (AK) gravel roads, and while my carbon gravel bike served well, I could see an advantage for at least a HT MTB on those surfaces.

DeadGrandpa

Holy Smokes, twocicle!!! I read about the Calfee-Ellsworth MTB, and recently considered an Ellsworth aluminum full suspension MTB that came up on a nearby Craigslist. The owner said the bike weight was 45 pounds, so I decided to look for a lighter solution. I appreciate the information, and will ask Calfee for their input. I'm a bit unsure of exactly how robust an MTB I really need, having never been on an MTB trail. Apparently, trees can reach out and grab the stoker while on a tight curve in the woods. Does any tandem belong on an MTB trail?

Paul J 

A disc brake MTB tandem would be nice to have. You could have two sets of wheels one wider and one narrower so you could adjust for different surfaces. I think a rigid design would be best for what you are considering. On the Tandem Facebook page a couple in Iowa are doing just this with their bike. Though it is not carbon it looks like a great multipurpose bike for riding as you describe.

TandemGeek

IMHO, carbon as a frame material is just another choice. However, unless you're building a rigid off-road tandem, the "benefits" of carbon can't truly be realized for off-road the way they can for road tandems since the lower-pressure tires and suspension systems absorb road shock but also induce a lot of their own deflection. The weight savings is also marginalized since the overall weight of an off-road tandem with it's heavier wheels, tires, suspension forks, etc. greatly diminish the net weight saving effect of losing 1-2 lbs out of the frame, if at that. After all, the Aluminum, Titanium and even some of the lightweight Steel alloys aren't all that much heavier than the composite frames once beefed up for off-road durability. However, as noted by brother two-cycle, composite frames can be repaired and modified in ways that aren't as economical for the other materials.

Just a few things to consider...

DeadGrandpa

I very much appreciate all suggestions and considerations offered here. Lacking personal mtb experience myself, your tips on the tradeoffs of various choices are very helpful.

With my laptop running now, I see that Calfee offers a Fat Bike Tandem in addition to the Front and Full Suspension MTB tandems. Since I will likely keep my old Santana for pavement (assuming that I can persuade my stoker), I have a new question: Fat Bike or non Fat Bike mtb tandem?

colotandem

The answer to your question is YES!!

I say it belongs wherever you want to ride it! See a few photos below.

As for choosing a Fat Bike tandem - They are a lot of fun, but if you are not riding in sand or snow, I would steer you towards a "regular" mtb tandem.

If you are mostly doing fire roads, the Fandango or Salsa Powderkeg might be a good option.

I'm with Tandemgeek. You will not see much of the benefits of carbon (other than light weight) on a fat tired bike.

There's a forum over on mtbr.com for tandems. It's not as busy as it used to be as people are posting more on Facebook.

We spend a disproportionate amount of time on the mountain tandems (vs. road) and are happy to answer any questions that you might have. Feel free to PM me.

Dan

akexpress 

here is my take on this for its worth. It is hard to have one tandem to do it all however I am just completing a Calfee adventure tandem. We commissioned an Adventure tetra with S&S couplers that would fit your bill quite nicely. It is designed around a 700c wheel geometry and utilizes a Whisky Cyclocross fork with thru axle. The frame geometry was modified to allow the different AC dimension to ride like a road bike. The rear triangle was designed to allow a large tire (the fork has lots of clearance). In this end I built a set of carbon 27.5 wheels using WTB Horizon 47mm tires that fit perfectly and match the diameter of 700c wheels and tires. This bike can use our Zipp 404 fast wheels , Velocity Aileron wheels, or the 650b large tire wheels without any modifications. I am building it as a drop bar DI2 XTR triple with hydraulic 785 brakes. Utilizing Middleburg modular cranks I can/could change to a double setup if we did a combo/supported unsupported trip so we could hang with our fast friends on the road by gearing it up. Our intended use is touring and gravel road touring and some simple single track. I don't think a carbon bike is any less durable and is certainly very repairable. We went with raw carbon no paint so it won't get paint scratches. Craig Calfee told me once that he could easily make us a travel repair kit that we could use to keep us riding in most situations if we had damage on an isolated trip. This bike is as close to a one quiver bike as I could figure out. It would probably work in trails like Moab but not really the best choice. We already have a tricked out Calfee tetra road and Ventana full suspension and Ventana fat tire tandems for use in the more extreme conditions. For what you are describing you probably don't need a full suspension tandem. I have a serious bike habit and a very enabling Stoker(wife) that loves to ride hence all the bikes. I'll post pictures soon but we have 3 ft of snow in the front yard so first ride is a ways off.

colotandem

^^^ akexpress and his wife are very similar to us. They like to ride together and have quite a few nice toys!

"Serious bike habit" - I may have to use that one.

Also, there are some good "all around tandems" that serve multiple purposes. akexpress is building just that.

I will use an analogy that I have in the past. Trying to come up with a do all bike/tandem is like using a leatherman. It's a great tool and can get most jobs done. But if I have the means to have the specific tools for a job. I will always reach for the screw driver or the can opener before the reaching for the leatherman.

We have the luxury of having a road tandem, full suspension mtb tandem, hard tail 29er, fat tandem and a cruiser just for fun. Each one has its purpose and since I have room in the garage, I'm keeping all of them!

CliffordK

Oops, did I mention FAT?

I've never liked the wide crankset Q-Factor on my fat tire cargo bike I built. Of course, one could theoretically build it so the Captain gets normal cranks, and only the Stoker (smaller person) gets the wide cranks.

But, it might be worth it to ride a 1 person FAT tire bike before investing $10K into a fat tire Tandem.

You might also try a couple of MTBs and Cross bikes on your gravel roads too. Are there any local bike rentals?

For your gravel roads, I would think the FAT tires would probably overkill, and will suck up excess weight that you're trying to save with CF. But, I will admit that I don't like my Cross bike on loose gravel, so perhaps one should experiment some.

You may also be able to run 650b wheels on your older Tandem.

akexpress 

I commute to work almost daily on my singles. It takes me twice as long on my fat tire bike vs the road bike. Same route same rider and similar quality bikes (both carbon) and on a mountain bike somewhere in the middle time wise. This translates to the tandems as well so a fat tire tandem would definitely not be my first choice as an only tandem. Colotandem and I were very fortunate to be very early adopters of the Ventana's entry in the fat tire tandem market and our bikes are set up very similar with carbon wheels etc and that are a blast to ride. My stoker doesn't mind cars or trees so we go every where. I have tandems because she is faster on singles than I am and I don't get dropped but we sure have fun on the tandems.

twocicle

^^^ Yes, the Q-factor/stoker issue is a major impediment to us getting virtually any mtb tandem, at least from my somewhat casual research, aka online spec shopping.

My wife seems to be past the point of no return as far as adapting to anything wider than 158mm Q. She used to ride her Rockhopper single mtb w/triple cranks without problem, but time/age seems to have killed that option because she no longer can ride it without developing pain issues. So, we're pretty much stuck to our narrow Q road riding. I don't see a 1x (which might be narrow enough) setup being enough gearing to make a mtb tandem very useful for trail riding.

My wish list was to grab something somewhat economical like the Fandango for basic fire road riding.

DeadGrandpa

I rode my Jamis Renegade "adventure" bike on some gravel roads last summer. Loaded with bikepacking bags and touring, I found it kinda top heavy. Changing lines I hit some loose gravel and took a slide that got me some nifty road rash along my entire right side from calf to shoulder -- yet only scraped a quarter sized hole in the shoulder of my shirt. I dunno. What size tire prevents loose gravel slides? Washboard was annoying with no front suspension, but it's my stoker that I worry about for the bumps.

This is the listing that got me excited until the seller quoted 45 pound weight. Should I reconsider?
https://greenville.craigslist.org/bik/5990975166.html

Q-Factor? I never heard of that. OMG, now I have more to study. My hard drive is already full!!

DeadGrandpa

Dude, I count 4 tandems. That is awesome. Plus your single bikes... Just awesome.

mtseymour

If you're willing to pay the premium, carbon is the ideal material for mtn tandems or single mtn bikes. All the top full-suspension mtn bikes from Specialized, Trek, Cannondale, Santa Cruz, Calfee, etc are carbon because they're light, tough, and can be made into a wide range of geometries. Carbon frames (road and off-road) are more fun to ride because they're quieter and track better in rough terrain. And they're also repairable.

DeadGrandpa

Thanks for the recommendation. I knew that I liked riding my carbon adventure bike best, but hadn't been able to specify exactly why. My newest bike, the steel folder, just hasn't grabbed me yet the way the carbon one has.

My concern was about the double load the tandem carries. I think that concern has been assuaged. I think I need a carbon mtb with front suspension. I do thank all for sharing your experience and knowledge. But don't stop if you want to add something.

jnbrown

Another Calfee owner here, I also agree the carbon tubes Calfee uses are very robust and could be used off road.
I would be concerned though if hit by a rock that was kicked up or crashed it could be damaged more easily than say titanium. Its a lot of money to pay for something that might be damaged and the benefits are not as tangible compared to riding it on the road.

akexpress 

You might want to contact Alex Nutt at mtbtandems.com he is a wealth of knowledge and a dealer for many brands including Calfee. He sells more mountain tandems then anyone else probably more then all others combined. Tell him Mark from Alaska and Dan from Colorado sent you, he will take good care of you.

DeadGrandpa

I googled titanium MTB tandems and got basically nothing. I'm gonna have to go with carbon. My one carbon adventure bike held up to a slide/crash on gravel, and that's basically where I think I will be riding. Runs down ski slopes are not in my future. I really prefer climbing hills to going downhills at insane velocities.

Dean V

We got a Cannondale 29er a few months ago specifically for riding the gravel roads in our area. I have been very pleased with it.
Fairly light, can take quite a big tyre and all the componentry works well.