# ECDM Geometry



## switchbacktrog (May 10, 2013)

Has any one felt the need to slacken the fork rake on an ECDM using an Angleset? The 70.4 degrees quoted by Ventana seems a bit steep to me with my limited tandem experience.

Our new ECDM feels a bit too light and sensitive on the steering for my liking. We test rode one fitted with a Fox Float 36 and that one was just right. Ours is fitted with the new Pike. 90mm stem. Tapered head.

I've emailed Ventana for advice.

I just want to load it a bit without going so far that it becomes floppy during low speed manoeuvring.


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## reamer41 (Mar 26, 2007)

Old thread....

Did you ever come up with anything to give you a better feel? How long is the pike? Or I guess I should ask if the AtoC is much greater than the frame was designed for?

I've got an '06 ECDM (26" wheels) and my fork is taller than recommended, and the steering is like you describe. I think I'm going to space the fork down another 1/2" and see if it improves it. I'm currently on a Fox 40 at either 5 or 5.5"travel. I can only space it down so far before I will have to shorten the springs....

I dragged the old KHS tandem out of the garage the other day and I really like the way that bike steers and handles better than the ECDM. But it has a fork that is (close to) the recommended A to C.


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## PMK (Oct 12, 2004)

reamer41 said:


> Old thread....
> 
> Did you ever come up with anything to give you a better feel? How long is the pike? Or I guess I should ask if the AtoC is much greater than the frame was designed for?
> 
> ...


A great example of how two similar machines, used in defferent locations prefer different setups.

We also have an 06, with 26" wheels. Also run a Fox 40, and have no concerns with handling. Our 40 has had the traveled decreased and runs a firmer spring.

If I had one complaint about the 40, it is the style of triple clamps and offset axle limit the left and right steering lock angle. Most times a non issue, but there are a few local sections we seldom ride clean since I can not turn the front wheel enough to get the tandem around the corner.

PK


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## reamer41 (Mar 26, 2007)

Paul, how much have you decreased the travel? Or should I ask, how much travel are you running? My comments regarding handling really only pertain to slow speed riding and maneuvering.

I totally agree about the steering lock. I've ridden some tight turn with the fork bumpers on the frame the whole way around. It's a little unnerving! And there are those tight spots which are unridable due to the limited steering lock.


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## PMK (Oct 12, 2004)

reamer41 said:


> Paul, how much have you decreased the travel? Or should I ask, how much travel are you running? My comments regarding handling really only pertain to slow speed riding and maneuvering.
> 
> I totally agree about the steering lock. I've ridden some tight turn with the fork bumpers on the frame the whole way around. It's a little unnerving! And there are those tight spots which are unridable due to the limited steering lock.


As for the travel, can I reply in a few days when I get home?

Yes slower speeds are always a bit more challenging but not too bad, except for dealing with super tight turns.

Before going to a change on the front, have you checked the rear sag? Running the RP23, make certain you have a small air can or reduced air volume. For rear sag, run 1/8" with the stoker alone on the bike.

With the smaller air volume, the bike will not wallow and holds the rear end higher up. Not sure what setup your bike came with, it may already have a smaller air can.

This would be an easy bike to sort out if you were local.

PK


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## switchbacktrog (May 10, 2013)

reamer41 said:


> Old thread....
> 
> Did you ever come up with anything to give you a better feel? How long is the pike? Or I guess I should ask if the AtoC is much greater than the frame was designed for?


We had the Pike reduced to 140mm from 150mm travel.

Ventana suggested to steepen the head angle by 0.5 degrees(as opposed to slackening it) as the frame is designed around a 100mm fork, but can go to 120mm. I could only get a 1 degree AngleSet at the time and this was fitted to steepen the head angle, I was assured by the shop that I wouldn't notice the difference.

The steering weight improved enough for me to go back to a 60mm stem from the 90mm I fitted, as was intended for the top tube length specified in the build.

The problem now is that it's very difficult to steer on a camber or in a depression/rain gully as the steering is always trying to kick you down the slope to the bottom and makes it very hard to change your preferred line to get out of the low point. It's come to the point where I have to slow down to get the bike back under control, bouncing from one side to the other. On a slow cambered corner the front feels like it wants to "tuck-under".

It's due into the workshop tomorrow to have the AngleSet swung through 180 degrees to slacken the angle by 1 degree from original. Everything I've read on various forums suggests this will work, and it was my original thought to do this. The steering will be slower than before, but I don't mind that if it fixes the extreme twitchyness. I'm not convinced that you need the same steering speed as a solo bike, as you can't really flick it round the trees in the same way.

The suspension company I use has also suggested running less sag on the rear to prop it up more.
Welcome to Sussed Out Suspension UK - The Eastern regions most dedicated mountain bike (MTB) suspension centre! Based in Essex/Suffolk not far from Thetford Forest in Norfolk! UK Mondraker & GT bikes dealer! Fox, Rockshox, Cannondale, Cane Creek, Mag

I will report back in a few weeks time when we've had the chance to try it.

John


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## reamer41 (Mar 26, 2007)

Very interesting, John! Thanks for posting that. I'm interested to hear what the change to slacker steering yields in feel. 

--Charlie


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## PMK (Oct 12, 2004)

switchbacktrog said:


> We had the Pike reduced to 140mm from 150mm travel.
> 
> Ventana suggested to steepen the head angle by 0.5 degrees(as opposed to slackening it) as the frame is designed around a 100mm fork, but can go to 120mm. I could only get a 1 degree AngleSet at the time and this was fitted to steepen the head angle, I was assured by the shop that I wouldn't notice the difference.
> 
> ...


I would agree with less rear sag or a small air can to reduce mid stroke wallow. If you already run a small can, you may be able to lessen the volume more if you notice the rising rate is not enough.

As for the front, twitchy is a good description. Consider though that compared to a MX race bike, the bicycle has little ability to change fork offset. Front end geometry is not solely about headtube angle. It is a combination of headtube angle, offset of the axle in regards to the steering axis centerline and wheel diameter.

So even though you could run two forks, both 100mm as an example, one fork may have a different offset than the other, which will result in a different trail dimension. This change can improve or make worse cornering on account of how the tread on the tire side knobs bites the dirt. Head angles too steep will tend to run more on the tires center, whereas slack angles will also run on the tire sideknobs. The difference is in how everything works together to put weight on the front tire.

With MX bikes, we are able to buy different triple clamp offsets. 2mm is a noticeable change.

Slack headtubes tend create a feeling of wheel flop, while steep angles become twitchy.

The comment about tandems differing from a single I would agree with 100%. Kind of the same, but a lot different.

Fun technical topic...

PK


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## reamer41 (Mar 26, 2007)

Ha!
Pulled off a tight, descending, loose, washed out, switchback today! It was a bit sketchy, and Joyce was a bit 'concerned' but we rode through it. It wouldn't have been terribly fun to have had to bail in that spot.... Steering was not on the locks the whole time and the front end felt a bit vague at the bars.

Is that slow-speed looseness what you're trying to firm up, John?

When I had a Marz Jr. T at 170mm (had been told it was shortened but hadn't been) it felt like the front tire contact patch was perched on an ice cube (as far as feel, not traction). Shortening the travel helped. Never really liked the Jr T, though.

Also, for the record.... I do have the small air can on the rear Fox. And I have the rockers that give a 2.5:1 ratio yielding 5" rear travel. Those rockers did raise the back end a bit. When I lived in Phoenix, AZ it was very rough and rocky going and the extra travel was a nice thing (but may have overwhelmed the Fox @285psi). Now living in Prescott 4" would be fine, but don't want to lower the back (without lowering the front).


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## PMK (Oct 12, 2004)

reamer41 said:


> Ha!
> Pulled off a tight, descending, loose, washed out, switchback today! It was a bit sketchy, and Joyce was a bit 'concerned' but we rode through it. It wouldn't have been terribly fun to have had to bail in that spot.... Steering was not on the locks the whole time and the front end felt a bit vague at the bars.
> 
> Is that slow-speed looseness what you're trying to firm up, John?
> ...


Consider also for the rear, the shock length we run comes in two travel variations. Stock is 2.0 and Fox also offers a 2.25. Never fitted a 2.25. If someone tries it, cycle the entire suspension movement before riding it to ensure no interference of the shock to the frame or links.

PK


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## reamer41 (Mar 26, 2007)

Hmmm... I have a 2.25' shock from a Ventana El Ciclion. I'll take a look at that with the 4" and 5" rockers on the ECDM and see how it looks. I don't recall if the eye-to-eye length is the same or ¼' longer than the stock unit on the dcdm. Totally understand about cycling suspension with new rocker and/or shock! 

I don't need more rear travel, just better travel.


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## switchbacktrog (May 10, 2013)

reamer41 said:


> Ha!
> 
> Is that slow-speed looseness what you're trying to firm up, John?
> 
> Also, for the record.... I do have the small air can on the rear Fox.


Compared to JD Tandems' demo bike with a Fox 36 @120mm, I thought ours was too "light" on the steering effort, but put this down to the fork length(150mm at the time) and the shorter stem. I tried a longer stem as a trial(90mm) and it did increase the effort but obviously increased the reach too much. So replaced it with the short one, decreased the fork travel to 140mm and fitted the AngleSet.

Since then, I've put shorter stems on my solo bikes as well. This lighter feel took some getting used to but now it feels fine, so perhaps the tandem set-up wasn't too far wrong in the first place, and it was just me that was the problem .

Anyway.................The AngleSet has now been rotated by 180 degrees to give a 1 degree slacker head angle to standard. Trials on the road seem OK, with the steering effort pretty much the same as before, with no apparent adverse affects, even when doing slow speed manoeuvres :thumbsup:.

I won't get the chance to take it on the trails until next weekend, but hopefully the "twitchyness" and side-slope deflections will have gone as well.

As for the air can size....................It's one of these as supplied from Ventana. No idea what the air can size is. We run it at the standard 25/30% sag and with the "trail adjust" at setting 3 (firm). It does still "blow through" on occasions so perhaps we need to add a bit more air.


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## reamer41 (Mar 26, 2007)

PMK said:


> Consider also for the rear, the shock length we run comes in two travel variations. Stock is 2.0 and Fox also offers a 2.25. Never fitted a 2.25. If someone tries it, cycle the entire suspension movement before riding it to ensure no interference of the shock to the frame or links.
> 
> PK


I measured the 2.25" shock I have. The uncompressed eye-to-eye length is the same as the stock 2" shock. So the longer travel shock wouldn't be a benefit as far as rear ride height, just allow stroking further on a big hit -- as near as I can tell.

Any other thoughts Paul? Am I missing something there?


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## reamer41 (Mar 26, 2007)

switchbacktrog said:


> .
> 
> As for the air can size....................It's one of these as supplied from Ventana. No idea what the air can size is. We run it at the standard 25/30% sag and with the "trail adjust" at setting 3 (firm). It does still "blow through" on occasions so perhaps we need to add a bit more air.
> 
> View attachment 938739


That's the small air canister.


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## PMK (Oct 12, 2004)

reamer41 said:


> I measured the 2.25" shock I have. The uncompressed eye-to-eye length is the same as the stock 2" shock. So the longer travel shock wouldn't be a benefit as far as rear ride height, just allow stroking further on a big hit -- as near as I can tell.
> 
> Any other thoughts Paul? Am I missing something there?


Not missing anything. I offered the suggestion simply to set middle ground for you. Assuming there is no clearance issues with the 2.25 shock, you could have more travel than a stock rocker ECDM but less than a long travel rocker ECDM. Changing the leverage ratio will help hold the rear end up, keeping the steering angle more vertical, and minimize wallow or blowing through the travel.

You made an excellent comment also.

*I don't need more rear travel, just better travel.*

One thing I don't know, is do you have a set of 4" rockers?

I'm suggesting things (2.25 shock) to keep the stoker content with 4.5" rear travel so slightly less than now, but helping to hold the rear end up from a better leverage ratio.

Our friends with a newer ECDM 29 had weird handling like you guys are describing. For him to dial in the how the front end cornered, tracked, gain low speed agility and minimize front wheel flop, he gave up rear travel and runs very little rear preload (more air pressure).

Let me get home and pull out our ECDM. I will take a couple of measurements and post back. As a rough recollection...

Fork is 150 (6") mm travel, front sag with both riders on is around 1.5" or 25%.

Rear is set for 1/8" (shock stroke) with stoker only and may drop to 1/4" with both riders, so about 12-15%.

This is two riders ready to ride with all gear.

But I will double check this weekend.

Consider also, with me running a DHX 5.0 air rear shock, by design of the shock it has adjustable bottoming control in addition to propedal. So this also offers me adjustability to prevent wallow on midstroke and helps change the true rising rate of the entire rear suspension without a change in leverage ratio.

PK


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## reamer41 (Mar 26, 2007)

Thanks for your comments, Paul. 

I do have the 4" rockers. I will dig them out. I'll also see if there's clearance to run that 2.25" shock. If nothing else it's seen less and easier use than the current shock on the ECDM.


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## PMK (Oct 12, 2004)

FWIW, our 40 is 145mm or about 5 3/4" front travel.

PK


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## PMK (Oct 12, 2004)

I will try and scan some pages that will explain much of this and post them here.

Good handling and / or good suspension is a best compromise of many parameters and settings.

So often steering angle is stated as the culprit, but really it all sorts of things. Rear sag, rear spring rate, and overall rear suspension action is a definite factor to proper front end performance and handling.

FWIW, it is more difficult to get good suspension on a bicycle than on a motorcycle. Much has to do with the rider being the larger mass on the bike, and without a throttle, it can be tough to get good suspension action.

PK


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## reamer41 (Mar 26, 2007)

PMK said:


> FWIW, our 40 is 145mm or about 5 3/4" front travel.
> 
> PK


Mine is pretty much the same. (I don't remember exactly how close the wipers come the the bottom triple clamp when bottomed -- close, though.)

Next time I have the fork opened up I will add another 1/2" spacer. Might have to shorten the springs, though. (Which are the heaviest Fox offers. I weigh 210, and stoker about 160.)


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## PMK (Oct 12, 2004)

reamer41 said:


> Mine is pretty much the same. (I don't remember exactly how close the wipers come the the bottom triple clamp when bottomed -- close, though.)
> 
> Next time I have the fork opened up I will add another 1/2" spacer. Might have to shorten the springs, though. (Which are the heaviest Fox offers. I weigh 210, and stoker about 160.)


Team wise, about the same. Firm the rear before dealing with the front.

PK


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## switchbacktrog (May 10, 2013)

reamer41 said:


> Very interesting, John! Thanks for posting that. I'm interested to hear what the change to slacker steering yields in feel.
> 
> --Charlie


We've had it out on some fairly tame trails and there is a small improvement, but not as much as I'd hoped for, although it does seem to have more of an affect in improving the stability at higher speeds. We will have travel further away to try it properly as we tend to lack much in the way of "terrain" where we live. I'm pretty sure that the increase in shock pressure to prop-up the rear may have helped more than slackening the head angle. I seems odd that changing from 1 degree steeper than designed, to 1 degree slacker makes so little difference :???:. Perhaps the fork travel is still too long @ 140mm.

John


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## switchbacktrog (May 10, 2013)

An update................just back from a weeks riding in the Forest of Dean where we could do a proper test on some steeper and rougher terrain. Much the same as before TBH. I then increased the front tyre pressure to 30psi having found an old "tyre pressure thread" on here. This was big improvement on the tendency for the steering to grab the terrain on a camber. I'd previously been running at around 26psi with a 2.4 tyre. It does seem that quite a few folks are running 35psi though, can't really bring myself to run that high as it must compromise grip at that pressure, and perhaps cause you to "ping" off roots and rocks. I should have realized how much tyre pressure affects the steering as the "grabbing" problem was very noticeable when we developed a slow puncture. Perhaps I'm still used to using "single bike" knowledge and still have a lot to learn about tandem set-ups.

We managed over 30mph on one of the smoother downhill tracks so it can't be too bad now. The next plan is to remove the AngleSet and return the HA to standard as I'm not convinced the 1 degree HA change + or - made a noticeable difference TBH.

The steering is still far too light for my liking so might fit a Hopey steering damper to smooth things out more. Again, an old thread brought this device to my attention as I'd not heard of it before and the reviews seem to be very positive with regard to what I'm trying to achieve.

Another problem we had was the stoker coming detached from the pedals on fast sections with very small rocks or roots (flat pedals and 5-10 shoes). This was cured by switching the shock to the "descend" mode which is something we'd not bothered with previously and increasing the rebound damping by two notches. We normally just leave it in "trail" mode. I put the Pike fork into fully open position for the fast downhill sections as well, and this was far smoother. I can't believe how much difference these two changes made.


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## switchbacktrog (May 10, 2013)

Well, I fitted the Hopey steering damper yesterday and it took me about 3 hours. It was a case of measure 6 times and cut twice to get the steerer tube to the correct length to fit both the damper and rider. Took the AngleSet out first and replaced the standard angle Hope head-set with the base-plate sandwiched between the head-tube and the top bearing cup. Then re-assembled it all with the base plate and set the pre-load before fitting the rest of the damper unit. I must have had the fork in and out about 8 times before I was happy to do the final assembly.

































And the result.......................superb. Can't believe it's taken me so long to get it just right. The damper feels a bit odd when you start to turn off the centreline as it starts to load, but once you are in the corner it just feels like there's the right amount of load on the bars. It took a couple of miles to twiddle with the adjuster and get used to it, but we ended-up absolutely flying round the curves in a nice smooth line rather than turning the curve into a multi cornered line. We even got the back end sliding a couple of times, also clipped the Stokers bars on trees a couple of times as we were leaning into the bends more which also caused a few pedal strikes as well. I think the extra speed was due to me having more confidence to maintain speed right through the bend rather than backing-off before.


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## Sanchofula (Dec 30, 2007)

Okay, so when you say the front end felt light, was this when climbing or descending? 

Did it feel "floppy", ie have tendency to fall over to one side when turning sharply at slow speeds?

It's curious that everyone in this thead is running so much travel, esp when Ventana spec'd the ECDM for 100mm. A slackened front end can be a bit wonky and will tend to wander and flop. 

A slack front end is not so much of a problem on a solo bike where you can manual and you have less load to manage, but on a tandem it makes you weave like a drunken fool, esp. on narrow trails with sidehill and rut issues..

The Pike can be reduced to 120mm, that might be worth considering as a trial. 

As to rear suspension, you might want to look into volume spacers, I'm not a Fox expert, so I don't know how they manage this, but with a Rockshox you can add volume spacers to ramp up pressure on big hits without reducing small hit sensitivity; same thing on the Pike.

I also thought about the steering dampener, but I didn't want to slow the return to center, plus it seemed like it wasn't solving the problem. We went to a shorter fork (80mm) on the Jefe and it handles better. Sometimes folks try to add more suspension, when what they really need is better suspension.

Just a note on set up, but it looks like you have 2 x 20mm head set spacers under your bars. That's a lot of spacer, which can cause fork steerer failure from excessive leverage; one inch is considered max. Another thing to consider is that having the bars high will reduce stability. You might want to drop your bars incrementally and see if that slows down the action.

If you're running a 2.4, like an Ardent EXO, you don't need 35psi. We are a team of 350# and we never run more than mid 20psi. Hard tires bounce off obstacles and slide around too much.

If you already know all this, then just disregard 

It's kinda fun playing with bike/tandem set up!


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## switchbacktrog (May 10, 2013)

Thanks for the great information . Replies in BLUE

Okay, so when you say the front end felt light, was this when climbing or descending? 
Both

Did it feel "floppy", ie have tendency to fall over to one side when turning sharply at slow speeds?
No

It's curious that everyone in this thead is running so much travel, esp when Ventana spec'd the ECDM for 100mm. A slackened front end can be a bit wonky and will tend to wander and flop. 
I tried an AngleSet to steepen the angle and it made very little difference.

A slack front end is not so much of a problem on a solo bike where you can manual and you have less load to manage, but on a tandem it makes you weave like a drunken fool, esp. on narrow trails with sidehill and rut issues..
That's what I had.

The Pike can be reduced to 120mm, that might be worth considering as a trial. 
That was going to be my next project, shouldn't need it now.

As to rear suspension, you might want to look into volume spacers, I'm not a Fox expert, so I don't know how they manage this, but with a Rockshox you can add volume spacers to ramp up pressure on big hits without reducing small hit sensitivity; same thing on the Pike.
I've done this on the Pike.

I also thought about the steering dampener, but I didn't want to slow the return to center, 
The Hopey damper only works in one direction, the return to centre is not affected.

Just a note on set up, but it looks like you have 2 x 20mm head set spacers under your bars. That's a lot of spacer, which can cause fork steerer failure from excessive leverage; one inch is considered max.
I didn't know that.
EDIT: _Just done some research and from what I've found, it seems like 20mm is the max for a carbon steerer, around 40mm on an aluminium one and just about what you want on a steel steerer which the Pike is. The manufacturers test them with the stem right at the top of an un-cut steerer tube, although the total stack height will be different depending on the frame. Some of this info was road based so the loading is nowhere near what we endure.
_
Another thing to consider is that having the bars high will reduce stability. You might want to drop your bars incrementally and see if that slows down the action.
Could be worth a try, but the damper seems to do the job at the moment.

If you're running a 2.4, like an Ardent EXO, you don't need 35psi. We are a team of 350# and we never run more than mid 20psi. Hard tires bounce off obstacles and slide around too much.
That's exactly what I thought. We were previously running 26psi, currently at 30psi which seems to work well as we are getting very little deflection from the terrain now, this was the case before the damper was fitted. For the above reasons, I can't bring myself to increase the pressure any more, and don't need to now either. I might try dropping it in 1psi increments to try and find the "sweet spot".

I don't really like treating the symptom rather than the cause, but in order to keep the higher bottom bracket height that 140mm gives, I reckon that where we are now is pretty much as good a compromise as is possible at the moment, although I will probably drop the stem a bit.


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## Sanchofula (Dec 30, 2007)

A higher BB is crucial, I absolutely hate having pedal clearance issues. I run the shortest cranks I can get (170mm) and the tallest tires that'll fit my fork (29 x 3").

I like to play with outfitting during rides, sometimes I'll switch stems and change the stem height, which gives my stoker and dog a nice long rest 

Bar width is personal, but a wider bar tends to cause "overcontrol" as the smallest movement is amplified; of course bigger bars offer more leverage. I run wide bars, 730mm, previously ran 760mm.

It's also worth trying shorter stems, I've run from 45mm to 90mm, the rule is narrower bar + long stems or wider bars + short stems.

Next year we're going to commission an FS frame from Davinci (if they'll accommodate me), independent pedaling system, 83mm BB, 120mm fork, 100-110mm CC shock, Boost or 150/177 hub spacing, sliding dropouts with capacity for 26 x 4 to 29 x 3, and a high BB (12+" at the Stoker).

I think all the MTB tandem frames need to be built around a 120mm fork, there are no decent 100mm fork available nowadays, the standard is 120mm and it seems to be here to stay.



switchbacktrog said:


> Thanks for the great information . Replies in BLUE
> 
> Okay, so when you say the front end felt light, was this when climbing or descending?
> Both
> ...


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## laksboy (Sep 4, 2007)

Nurse Ben, Did you ever commission that Devinci? I'm curious about their design and how they ride compared to an ECdM. I'm on a 12 year old ECdM and want to upgrade. Mainly for a modern fork (Fox 36 TALUS and the 27.5+ tires).


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## mtbmitch2 (Sep 24, 2007)

what offset works best on a fs tandem, 44 or 51?


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## ebnelson (Oct 30, 2006)

We've always used the standard Fox 51mm offset on our 29er ECDM. The ECDM headtube is fairly steep, but the low speed handling goes to **** if the forks axle to crown is much over the Ventana specification. Decreasing the trail may help for low speed turns but I'd have a bunch of toe overlap if I bring the front wheel closer. Our ECDM has a 24" TT with a 70mm stem. Our next frame will have a longer TT and shorter stem.


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## laksboy (Sep 4, 2007)

Anyone see the announcement on Ventana's facebook page?
https://www.facebook.com/ventanausa/
New ECDM, 27.5+ stock with boost spacing. Room for 3" tires.
Anyone know if the geometry has changed at all (Longer cockpit + more standover)?


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## mtbmitch2 (Sep 24, 2007)

laksboy
I just built up the ECDM27.5 boost spacing. Boost Helm fork at 130mm travel. My sears angle reader needle is right about 71.5 degrees. So I don't think the frame has changed. This frame is actually just a 29er frame with the modified rear triangle. Running 38mm LB rims with 2.8 nobby nics btw.
Mitch


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## laksboy (Sep 4, 2007)

On the wheels, any reason you didn't go for the 40 or 46mm ones with the fatty tire?? I assume you went the "EN" extra strong lay-up, and did you get 32 or 36 hole? My front will be a dual position Lyrik or 36. Once I get my current ECdM sold, that is! What's the rest of the spec? I'm leaning towards a 1x XT-di2 and maybe a wider range (than XT) cassette. Also curious, are you running the timing chain on the left or the right?



mtbmitch2 said:


> laksboy
> I just built up the ECDM27.5 boost spacing. Boost Helm fork at 130mm travel. My sears angle reader needle is right about 71.5 degrees. So I don't think the frame has changed. This frame is actually just a 29er frame with the modified rear triangle. Running 38mm LB rims with 2.8 nobby nics btw.
> Mitch


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## mtbmitch2 (Sep 24, 2007)

Only going 2.8 wide on the tyres so 38mm rim is wide enough. Yes on extra strong layup which requires 14mm nipples. Timing chain on the left. Running Middleburn square tapers with triple (22,30,38) and 11-40 sunrace x3 rear cassette, 10 speed. Lots of mountains here in Idaho so prefer to spin at 57 years old. Note, Crankarms not timing in picture. 203mm rotors with hope 4 piston calipers. Going to add a air volume removal spacer to try to stop a bit of wallowing in the midstroke. I think the shock needs some revalving but will try this first. Low speed rebound only 5 clicks from full in and low speed compression pretty far in also. Wife and I will not be riding aggressive stuff so wheelset should be fine at 32 front and 36 rear on Hadley hubs with DT Swiss 2.0-1.8.2.0. Will reweight since I have got a bit of weight off. Initially at 41.4 pounds


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