needmorebikes

Trying to get to the straight scoop on outfitting a tandem with a front fork.

When front suspension first started appearing on tandems, they were the triple clamp / double crown style (i.e. Rock Shox Boxxer). That made sense to me given the extra weight of a tandem.

Now I'm starting to see tandems with the typical single crown forks (i.e. Rock Shox Psylo). Question is:
Has the industry now learned that single crowns forks are actually stong enough for tandems or are only certain single crown forks acceptable for tandems?

Any info is appreciated.
Thanx,

stapfam

The answer is both. The cheaper, or lighter weight single crown forks will not take the punishment that Offroad tandeming will throw at it. The cheaper units are not up to grade, and the lighter weight units will not have the strength.

What is more important is "Will the manufacturer warrant his forks for tandem use?" and "Are heavy enough springs available?"

I have used two forks. Initially I used a Marzocchi Freeride dropoff as both points were covered. They were good enough until I put Disc brakes on the Bike. Then I found the forks flexing a bit too much for comfort, and they were only QR, which is not the ideal for a Top grade Disc unit.

Then I went to Boxers, and once again they were covered by both points. The triple crown definitely stopped the flexing under braking, and the 20mm axle gave me more confidence. Actual suspension was the same on both forks, and to be honest, if I gone for 20mm axle in the first place on the Marzochi's, I probably would not have changed them. Saying that- they were flexing a bit too much for my liking, so how long they would have lasted is any ones guess.

Please remember that I do use the Tandem aggressively, and all my components go through it. If you are not contemplating Rocky downhills taken at 35+ ( and the plus is a good plus), You are not prepared to put around 2lbs of extra weight on the front end of the bike, and your trails are generrally smooth, Then a good quality single crown that has heavy enough springs and has the manufacturers warranty for tandem use is good enough. I would still recommend the 20mm axle though if Disc brakes are used, or if you want the extra confidence of a solid axle with Rim brakes.

TandemGeek

IMHO, what they've figured out is that in the never ending search for gram savings a single crown fork can be produced that will not fail under the weight of an off-road tandem and folks will buy them. Now, as for how well those single crown forks work compared to a tandem-rated dual-crown fork like an ATC T5 or Stratos S5, even with a rigid axle the single-crown forks will not track nearly as well as the dual crown forks. I say this noting that our favorite off-road tandem builder and friend Sherwood has had some nice things to say about the single crown forks. Perhaps the terrain out in Northern California is more conducive to an XC fork. However, at least here in the Southeast, Midwest, and much of the Eastern Seaboard, I have yet to find any single crown fork-friendly terrain that I'd want to spend much time riding.

As for how others we know view this topic, some have learned from first hand experience that two crowns are better than one. More specifically, some friends of ours from Ohio took delivery of a nice new Ventana ECdM with all the high-end, gee-whiz stuff last year (Rohloff hub, etc...) and opted for a Marzocchi Dirt Jumper single crown. They recently changed it out for an ATC T5 and are just now starting to enjoy the Ventana. Up and to the fork switch, the captain -- a very accomplished rider and captain -- and his wife could not for the life of them understand why everyone enjoyed riding off-road tandems so much as it was all they could do to control the thing on technical singletrack as the fork would not track well and was forever being twisted as the front wheel followed the ruts. However, once they installed the very beefy ATC T5 dual crown fork, the shearing action was gone... the tandem would go where they steered it and did not get whip-sawed by the ruts.

Bottom Line: If you're running on fire roads and in other places where you don't have to fight tree roots, rocks, waterbars and other obstacles that put high shear loads on your forks, a single crown may work for you. Frankly, I'd rather pay a little more and carry the extra 2lbs to be sure that I had the best possible handling that I could get from a tandem fork and you only get that with a solid axle and the stiffest possible stanchions and sliders you can get... that is to say, a dual-crown fork.

Brian

Mr. Geek, please enlighten me on the couple that swapped their DJ for a T5. I have been planning on doing the opposite. I may have to rethink this one.

TandemGeek

It's pretty much as I noted. They opted to go with the lighter DJ fork to offset some of the Rohloff's weight and, not having anything other than his single off-road bike's performance to compare it to since it was their first off-road tandem, they both found the tandem to be very hard to control on single track. As best as I can recall, they found the handling so unpredictable and unsettling that they didn't find off-road single track on the tandem all that enjoyable and couldn't figure out why so many others in our group did. If you look at the below photo taken during our last get together at Tsali you should be able to figure out which team I'm referring to and why they began to suspect their fork selection could have been the source of their handling woes.



For some context, our first off-road tandem was a Cannondale MT3000 with the OEM Moto FR-T dual crown fork. Even though the FR-T had a 9mm QR, the forks sliders, stanchions, and double clamps were so over-built that the fork was fairly immune to wheel sheer and tracked very well. Our next off-road tandem was a Ventana that we fitted with a very chi-chi Stratos FR4-T, also with 9mm QR. The Stratos was no where nearly as "stout" as the Moto FR on the Cannondale and I would constantly fight the steering on that bike and we often times found ourselves down on the ground when a rut or root would torque the front wheel. Of course, I didn't realize it was the fork until we replaced that tandem shortly thereafter with another Ventana but this one was fitted with a 20mm bolt-on solid axle on a Stratos S5-T: what a HUGE difference. You pretty much point it where you want the tandem to go, and that's where it goes. If you hit a rut and keep hold of the bars, the wheel doesn't twist.

Bottom Line: Having complete confidence in your tandem's handling and equipment is essential for both safe and enjoyable rides. The fork is no place to look for weight savings if you're tackling serious technical terrain, even if you're a lightweight team.

Brian

I guess the DJ will still be the best option when we decide to travel with the bike. The T5 kind of defeats the purpose of the coupled frame.

TandemGeek

You could always wrap the T5 in a towel and put in the bottom of a nice big duffle bag filled with the rest of your cycling gear, etc... instead of the 26" x 26" S&S cases.

Brian

All that bulk, and no QR20. The T5 was not designed for travel. A QR20 would change all that.

TandemGeek

It's all about trade-offs and compromises... go with whatever works best for you.

Brian

For travel, I think the DJ will serve us better. I have no complaints about the performance of the T5 though.

needmorebikes

Thanx for the great info. It's obvious from the data and your photo that you guys are way into tandems. Side note; you metioned owning a Cannondale tandem - I personally find it odd that this year's Cannondale MTB tandem comes with a rigid fork(?)

Brian

Yep. And Kenda K-Rads. "Off road" is a broad description, but they just call it a tandem mountain bike. Not really set up for rough stuff, just off the paved roads.

stapfam

When I first got my Tandem, it had Suspension forks on it that were not up to standard, so reverted to Rigid while I investigated a suspension fork. There were not too many problems with this, except the bodies went through a lot of punishment, and fast across lumpy ground was a NO-NO. There was no way the pilot could keep his vision in focus.

The actual styles of riding than any mountain bike will see will vary, and the Dale MT is a mountain bike. I know I am biased, but the heart of this beast- the frame- is probably one of the better frames around, so it is a bike worth building on. If you then add in the styles it is going to be ridden, then what sort of fork do you fit on it? Rigid will be fine for those that buy it for a comfortable road bike. It will even be fine for smooth offroad trails. Then you get the team that would like something to take the sting out of rough trails, then those that want to have suspension for a little bit more aggressive. Then there are those nutters that will want something that work on the Roughest trail at 50 mph downhill. (yes these nutters exist, and yes it is possible to do it)

I do not know the cost of the most suitable fork for full aggressive downhill, but if that was fitted as standard, then the purchase price would go up tremendously. I think that Cannondales have have taken the correct route in leaving the choice of after market Suspension fork to the purchaser. We are all different, so when the riding style has been decided on, then the appropriate fork can be bought to suit that style.

needmorebikes

After thinking about for a while, I came to the same conclusion. Similar to selling bikes without pedals; let the owner decide!
This makes sense for a tandem fork as double crowns can be very dear ($).

Brian

Alex has them on sale for under $600. Of course, you'll need a $90 Cane Creek headset, and a new stem, to use one on the Cannondale.

tandemonium

Anybody have a report on the Psylo / tandem combination? Were they OEM or user installed upgrades?