Rear shock on Ventana ECDM
#1
Member
Thread Starter
Join Date: Nov 2008
Location: Denver
Posts: 28
Bikes: Trek commuter, Frankenbike 29er, Intense Spider XVP, Meridian tandem, big green ECdM
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Rear shock on Ventana ECDM
I posted this over on mtbr.com's tandem forum but thought I'd post here as well -- seems to have a bit more activity & some very knowledgeable folks.
I recently purchased a used ECDM and had the LBS give it a once-over since I'm a poor bike mechanic. The only issue found was the rear shock (Fox DHX Air 5.0) isn't rebounding properly. Their recommendation was to have it rebuilt - about a $130 task. I'm wondering if that shock is worth the investment or if I'd be better off purchasing something new. If a new shock is the best route - any advice on which one?
Does anyone have input or advice on this? It's not an issue of trying to minimize cost - I would just like to have a good shock back there and want to make an educated decision.
Thank you!
I recently purchased a used ECDM and had the LBS give it a once-over since I'm a poor bike mechanic. The only issue found was the rear shock (Fox DHX Air 5.0) isn't rebounding properly. Their recommendation was to have it rebuilt - about a $130 task. I'm wondering if that shock is worth the investment or if I'd be better off purchasing something new. If a new shock is the best route - any advice on which one?
Does anyone have input or advice on this? It's not an issue of trying to minimize cost - I would just like to have a good shock back there and want to make an educated decision.
Thank you!
#2
Member
Thread Starter
Join Date: Nov 2008
Location: Denver
Posts: 28
Bikes: Trek commuter, Frankenbike 29er, Intense Spider XVP, Meridian tandem, big green ECdM
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Update: I rec'd some good advice on mtbr.com.
#3
Senior Member
Join Date: Mar 2013
Location: Grass Valley
Posts: 167
Bikes: Co-Motion Primera Co-Pilot, Trek Madone 3.1
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 13 Post(s)
Liked 0 Times
in
0 Posts
Buying new may not be quite so simple...
Shocks are, or should be, matched up the spring rate. Thus I would expect a spring/shock combination for a tandem to be quite different from one on a half-bike. True that adjustment on shock might compensate, at least somewhat.
Thus the question is if the OEM shock you have has been tweaked for the tandem application or did they just throw standard parts together and call it close enough?
Shocks are, or should be, matched up the spring rate. Thus I would expect a spring/shock combination for a tandem to be quite different from one on a half-bike. True that adjustment on shock might compensate, at least somewhat.
Thus the question is if the OEM shock you have has been tweaked for the tandem application or did they just throw standard parts together and call it close enough?
#4
Member
Thread Starter
Join Date: Nov 2008
Location: Denver
Posts: 28
Bikes: Trek commuter, Frankenbike 29er, Intense Spider XVP, Meridian tandem, big green ECdM
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Good point.
It's my understanding it's a stock unit & tweaked / adjusted for use on the tandem.
It's my understanding it's a stock unit & tweaked / adjusted for use on the tandem.
#5
Senior Member
Join Date: May 2008
Location: Royal Palm Beach, Florida
Posts: 1,236
Bikes: 2006 Co-Motion Roadster (Flat Bars, Discs, Carbon Fork), Some 1/2 bikes and a couple of KTM's
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 28 Post(s)
Likes: 0
Liked 1 Time
in
1 Post
I replied to you on MTBR. Hope it helped.
For us, I the Fox DHX 5.0 air has internal shim stacks very close for the ECDM, and I changed no shims during rebuilds. The clickers have a wide range and easily dial in and as I explained we adjust on the fly almost every ride.
The 5.0 air early style is a very good design.
PK
For us, I the Fox DHX 5.0 air has internal shim stacks very close for the ECDM, and I changed no shims during rebuilds. The clickers have a wide range and easily dial in and as I explained we adjust on the fly almost every ride.
The 5.0 air early style is a very good design.
PK
#6
Member
Join Date: Dec 2006
Posts: 35
Bikes: 2013 Co-Motion Robusta, Litespeed Classic,Litespeed Bella
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Just curious.......... did you consider getting in touch with the builder(Ventana) and asking them what they would recommend?
#7
Senior Member
Join Date: Nov 2007
Location: Anchorage, Ak
Posts: 620
Bikes: 2015 Calfee Tetra tandem,2016 Calfee Tetra Adventure Tandem, Ventana ECDM 26 mtn tandem, Ventana ECDM 29r full suspension Mtn tandem ,Ventana Fat tire tandem, Calfee Dragon Fly, Santa Cruz Carbon 5010, 907 Whiteout fat tire
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 57 Post(s)
Likes: 0
Liked 6 Times
in
5 Posts
Call Sherwood at Ventana he is very responsive and helpful.
#8
Senior Member
Join Date: May 2008
Location: Royal Palm Beach, Florida
Posts: 1,236
Bikes: 2006 Co-Motion Roadster (Flat Bars, Discs, Carbon Fork), Some 1/2 bikes and a couple of KTM's
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 28 Post(s)
Likes: 0
Liked 1 Time
in
1 Post
During AORTA 1 a few years ago, I talked with Sherwood about rear shocks on the ECDM. In simple terms, he mentioned the design of the frame and linkage rates / ratios were based on the current style of airshox. This was important since my main concern was having a new frame built and obtaining proper rising rate for a coil spring Ohlins style shock.
Ultimately, the ECDM we purchased used to strip parts off of, became our full suspension off-road tandem.
When we purchased it the machine had a Fox RP series installed on it. I did open the shock and revalve the shimstacks to a better setting. In the end though, once I installed the non tandem rated Fox 40 Kashima fork, the RP shock could n longer keep up. I then went shopping and have settled on the Fox DHX 5.0 air series. These have a ton of available adjustments both in compression and rebond along with a variable volume rezzy to dial in riding rate.
The OP posted also on MTBR, I responded there explaining that I would not make a change in the shock, but rather ensure the the unit has a minimum of 100 psi in the rezzy but 125 would be better and see if it cures the knocking rebound, which it should. He was quoted 130 for a rebuild, and honestly, that is a fair price if done by a quality suspension tuner.
PK
Ultimately, the ECDM we purchased used to strip parts off of, became our full suspension off-road tandem.
When we purchased it the machine had a Fox RP series installed on it. I did open the shock and revalve the shimstacks to a better setting. In the end though, once I installed the non tandem rated Fox 40 Kashima fork, the RP shock could n longer keep up. I then went shopping and have settled on the Fox DHX 5.0 air series. These have a ton of available adjustments both in compression and rebond along with a variable volume rezzy to dial in riding rate.
The OP posted also on MTBR, I responded there explaining that I would not make a change in the shock, but rather ensure the the unit has a minimum of 100 psi in the rezzy but 125 would be better and see if it cures the knocking rebound, which it should. He was quoted 130 for a rebuild, and honestly, that is a fair price if done by a quality suspension tuner.
PK
#9
Senior Member
Join Date: Nov 2007
Location: Anchorage, Ak
Posts: 620
Bikes: 2015 Calfee Tetra tandem,2016 Calfee Tetra Adventure Tandem, Ventana ECDM 26 mtn tandem, Ventana ECDM 29r full suspension Mtn tandem ,Ventana Fat tire tandem, Calfee Dragon Fly, Santa Cruz Carbon 5010, 907 Whiteout fat tire
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 57 Post(s)
Likes: 0
Liked 6 Times
in
5 Posts
Paul
i wish I had your suspension knowledge as I'm sure our Ventana and singles would really benefit from your expertise and ride a whole lot better.
Mark
i wish I had your suspension knowledge as I'm sure our Ventana and singles would really benefit from your expertise and ride a whole lot better.
Mark
#10
Member
Thread Starter
Join Date: Nov 2008
Location: Denver
Posts: 28
Bikes: Trek commuter, Frankenbike 29er, Intense Spider XVP, Meridian tandem, big green ECdM
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
I've been lurking on the various tandem forums for a while (here & on mtbr), figured there was plenty of real world experience, and just was looking for input on if the current shock was worthy. PMK has a big track record of shock advice, so as soon as he gave a thumbs up on the shock I figured I'd send it in for a rebuild. Going up to DirtLabs in Boulder today and I'll pick it up later this week. Will also be using them for their 'suspension setup service'.
With a big investment like this I feel comfortable spending some money up front to make sure everything is working as best as it can.
#11
Senior Member
Join Date: May 2008
Location: Royal Palm Beach, Florida
Posts: 1,236
Bikes: 2006 Co-Motion Roadster (Flat Bars, Discs, Carbon Fork), Some 1/2 bikes and a couple of KTM's
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 28 Post(s)
Likes: 0
Liked 1 Time
in
1 Post
As far as suspension and things that go along with it, I have been intrigued and passionate about it since the mid 70's. I enjoy helping friends but came to not like it so much as a business. Far easier to fix airplanes and feed the family than do shocks. Maybe you can come to AORTA 2 and we can get you dialed in for sag and clickers.Rebuilds or revalves would be tougher...bring your single also. See you in Asheville?
PK
Thread
Thread Starter
Forum
Replies
Last Post
Mainframeguy
Tandem Cycling
7
02-04-11 03:13 AM