# Suspension Fork Set Up and Wheels/Tires for Technical Terrain?



## Sam Jones (Feb 25, 2005)

I have described our current set up below and would appreciate any
comments or suggestions from you more experienced folks out there.

The terrain we ride is very technical with LOTS of rocks and logs and
in many sections is quite tight single track with turns that are
barely makeable on the tandem.

Our ECDM is set up with a Maverick DUC 32 and MTX rims with 2.4 WTB
MutanoRaptor Kevlar bead tires with tubes. We are a relatively light
team (180# captain and 102# stoker). We don't go bombing down hills
at high speeds and (at 128 years) don't have the horse power to
charge up hills in big gears.

What we have found that works the best for us so far is:

Run the DUC 32 (which has the full tandem set up) with max rebound
damping and about 110# of air which gives nearly 3" of sag. This
gets the front end down to the same place it would be with a 4" fork
and 1" sag - which makes is much easier to navigate the tight turns
and minimizes the "bounce" or rebound when going over rough rocks or
big logs at low speeds. For BIG logs, I can yank the bars up to get
full extension on the fork to minimize the impact. The only down
side of this set up so far is that we sometimes hit the captain's
chain wheel on big logs. (Sudden Stop) We have minimized this by
using 28 tooth timing sprockets mounted on the insides of the
spyders.

Run the tires at 25 or 26 PSI. This gives excellent traction and
again minimizes the "bounce" or rebound when going over rough rocks
or big logs at low speeds. It is amazing to watch the tire distort
when going over angled logs that look like they might otherwise kick
the wheel off to the side. So far (in about 5 rides of 5 to 20 miles
each with this LOW pressure) we have had only one pinch flat! I
attribute this to the fact that the tire is rather high volume which
is increased by the 34MM width of the MTX rim AND to the PRB (Pinch
Resistant Bead) design of the rim that puts a rather wide flat edge
on the rim to spread the "pinch" load over a large area.
http://www.bikeparts.com/search_results.asp?ID=BPC114462

I am probably going to go with the Stan's No Tubes rim strips and
sealer to further reduce the chance of pinch flatting (and maybe
reduce rolling resistance a little as well).

We have so far been quite pleased with the performance of these tires
on our rocky terrain (which doesn't have much gravel or sandy surface
that would require deeper tread). I have a 2.35 Kenda Tommac Short
Tracker (Semi-Slick) Kevlar bead tire that I may also try on the
rear. I have had very good luck with the 2.1 version of this tire on
the back of my single and they roll really well (we are horsepower
challenged)

Your comments or suggestions are welcome!


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## Lutarious (Feb 8, 2005)

*thoughts*

I agree about the 2.4 Mutano Kevlar. Great tire. I'm surprised you run them that low, but it sounds like it works.

I've been thinking about a Sus fork for our tandem, but I like the handling how it is. Not sure if the longer fork wouldn't make it "push" in corners, especially hauling A** on sand covered fire roads. Something like a really tough Z-2 Bomber with stiff springs and lots of damping might be choice. I dunno.....


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## cmckim (Jul 18, 2007)

*tandem fork*

I have always been suprised at how different forks feel on a tandem compared to a single. I suppose it's the additional mass, but they are so SMOOTH. We haven't done any offroad work on a rigid fork (even our first test ride had a bombshell fork), but I think that forks work much better on tandems. Like watching a motercycle fork work: the fork works and the motorcycle stays stable. I feel that the bike handling would be improved if you didn't change the geometry too much. Decent rebound would be a plus as well.
Depending on how much travel you want and how heavy your team is, one of the marzzochi heavy single crown forks could do great for you.
Try it you'll like it...


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## sparrow (Dec 30, 2003)

Sam
Seems you've got it all thought out. I was not blown away by the Maverick forks on single bikes, but seems several tandem users are happy with them. While not tandem rated, we've had good luck with Rock Shox Lyrik, Fox 36 and Marzocchi 66 models. Seems the Freeride world of MTB has brought a lot of good tandem-usable products into the world. 

I like having an air spring, or air spring assist on tandem forks to allow for ramp-up in spring rate at the end of travel to prevent bottoming.

You are right to run a stout front wheel, worlds of difference, control and safety wise.


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## BIke N Gear (Sep 27, 2004)

Sam Jones said:


> Run the DUC 32 (which has the full tandem set up) with max rebound
> damping and about 110# of air which gives nearly 3" of sag.


Sam,

Just curious what the "full tandem setup" is. I have a Ventana El Conquistador de Montanas as well as a Maveric Duc that is not being used. Didn't like it on my 26" bike. I have been contemplating putting it on the Ventana as a 69'er, by limiting the travel and putting 29" front wheel on the bike.

When I first mentioned this to Maverick (several seasons ago) they didn't recommend using their fork a tandem. Though they did say people were doing it.

Thanks,
Gary


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## Sam Jones (Feb 25, 2005)

BIke N Gear said:


> Sam,
> 
> Just curious what the "full tandem setup" is. I have a Ventana El Conquistador de Montanas as well as a Maveric Duc that is not being used. Didn't like it on my 26" bike. I have been contemplating putting it on the Ventana as a 69'er, by limiting the travel and putting 29" front wheel on the bike.
> 
> ...


I'm not sure of the history but I think Maveric now says their fork is OK for tandems. I think MTBTandems recommends them for teams under 350#

Ethan - the tech guy at Maverick gave me the following guidance:
1. change to 6Nm negative spring 
2. Put 15 ml oil in the air chamber 
3. Put 15 wt oil in the damper presssurized to 80 psi.

Regarding converting to a 29 - Since the ECDM is not designed for a 29 wheel you will end up with a very high front BB and standover and slower steering.


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## sparrow (Dec 30, 2003)

I think mtbtandems.com has Mavericks custom altered for tandem use right outta da box.


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## TandemNut (Mar 12, 2004)

The Maverick is rated for tandem use by Maverick. Our experience has been that, even with the "tandem setup" from Maverick, the fork is under-damped and slightly undersprung. For that reason, I've always recommended the fork for teams under 300 lbs. For those teams, the fork seems to do well. 
I've got a DUC on my 29'er single, with the tandem setup, and it's still borderline under-damped. I only weigh 250 or so.
Helluva fork, though. Wish we were lighter so I could build us the uber-light tandem. This would be the fork.


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