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Co-Motion Carerra review

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Co-Motion Carerra review

Old 10-04-14, 09:30 PM
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dstang12
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Co-Motion Carerra review

We purchased a 2014 Co-Motion Carrera five months ago. This is a review of this tandem after the first five months.

About our riding style. Our first tandem was used Burley Rumba that included the optional stoker carbon softbeam and a drum break. We are a 300 pound team and ride about 2000 miles a year on the tandem together. We live in Colorado at the front range of the Rocky Mountains. We do occasional group rides and also like to do a week long self supported tours using hotels. We are comfortable standing up on the tandem, but by no means as smooth as on a single bike. Compared to a single bike, we are slow going up hills, slow to accelerate, we hold our own on the flats, and just bomb going downhill. Due to our location, there is really no flat routes. Even our short regular routes have 500+ feet of climbing.

There is a tandem specific shop that is 1.5 hour drive from us. After several shop visits over a couple years, we decided to purchase the 2014 Co-Motion Carrera with the S&S couplers. We decided against the Rolf wheelset and substituted 36 spoke DT Swiss tandem hubs and Velocity Dyad rims instead. We also went with the Thudbuster seatpost upgrade. We decided to use the dealer that was 1.5 hours away (instead of having a local shop order it for us) because we liked the idea of having a shop that had tandems in stock that folks can try before purchasing. Here is a report of what we liked and didn't like after our first three months.

The Carrera frame is a work of art. The welds are spot on. The bends in the chain stays and seat stays truly gives this bike class. We love the fact that the lateral tube has been removed. There are several advantages to this. There are less S&S couplers which results in less cost, less weight, and easier dis-assembly & assembly of the frame when packing the bike into the suitcases along with more room in the suitcases. The only drawback from not having a lateral tube is that the stoker may have fewer water bottle mounts. We do not notice any flex in the frame at all. The frame is responsive as would be expected from a sport bicycle.

We also like the Gates timing belt. Because it doesn't have lubricant on it, we are not getting chain marks on our calves. It is also cleaner process when packing a bike into the suitcases. The belt is quieter while riding. We also have a Garmin cadence/speed sensor that we use a rare-earth magnet on the stokers pedal to get to work properly. On the Burley, which had a traditional timing chain, when we were pedaling slowly, the magnet would move the chain over to the magnet and clank against the pedal. This is not an issue with the carbon belt. The belt has a tension specification. There is a tool that can be purchased to perform this function, but we have had good luck using a iPhone with the Gates tension app. This results in one less tool needed when on a trip.

We found that the stock Continental 700x28 Gaterskins that came with the bike were too harsh. We have since installed the Continental 700x32 Gaterskins instead. On the rims and inflated to 100psi, these tires actually measure 34mm wide. The tires provide a smoother ride and we feel more connected with the road on the fast downhill descents with uneven pavement. Many folks claim that wider tires have more rolling resistance. We have found that the wider tires result in faster times on our regular routes. I don't think the wider tires add to the time climbing, but we do go faster downhill. Not sure if this is due to additional confidence due to the connected feel to the road or if the rolling resistance is less due to the lower pressure in the tires absorb the vibration more efficiently on uneven pavement. I think the key with wider tires is to make sure they are supple. Anyway the Carrera frame & fork has additional room for even a wider tire. I believe a 38mm wide tire (actual – not what is stated on the tire) would fit. We are currently not using fenders so I cannot comment on them.

The stoker liked the comfort of the softbeam that was on the Burley tandem. The hope was that the Thudbuster ST seatpost was an acceptable replacement. After a few rides, the stoker was adamant that this was not the case. We were able to return the Thudbuster to the dealer and then purchased an USE Sumo XCR seatpost. This seatpost has a longer travel, more shock adjustments, weighs less, and has a sleeker look. The most important fact is that the stoker finds that this is as comfortable as the softbeam.

We are generally happy with the breaking performance of the TRP Spyre 8” disk brakes. The combination of the rim and drum brakes on our previous tandem was superior, but since the drum brake is no longer produced, the TRP Spyre disk brake is acceptable...although I would be interested in looking at a braking system that had more power for the steep descents. We like that the disk brakes grab instantly in wet weather, unlike the reduced braking capacity on our previous bike with rim brakes. Another minor comment is that the front disk rotor pings the calipers when cornering sharply or when the front wheel kicks out a rock that we are going over. The use of a 15mm through axle skewer would likely correct this. Again, this is a minor annoyance.

We had initial setup issues with the Spyre brakes though. Initially, they would go instantly out of adjustment and would make terrible noises and vibration when activated. We e-mailed the dealer about this and they did not have a solution. We then decided to take it to a local shop due to the dealer not providing confidence for correcting the issue for a 1.5 hour one way drive. The local shop recommended to re-surface the brake mounts. The TRP Spyre requires tight tolerance to the mounting surface. Previously, Co-Motion used Avid BB-7 breaks that have a floating washer mount system that does not require this tight tolerance. The tool required to do the resurfacing operation is a specialty tool that not all bike shops have. They will also need to spend some time to create a jig to fit the 145mm rear drop out spacing. We had our local shop perform this on the front and rear break mounts. This resulted in a night-and-day difference.

We also had issues with proper shifting of the rear derailleur. It was obvious that the cable was sticking somehow. Tandems bicycles are unique in that a standard component group cannot be used due to its length and gearing requirements. Inspecting and lubricating the existing cable & cable housing resulted in no improvement. Contacting the dealer only resulted in a statement that the tandem should shift like a single bike. I then decided to replace the cable housing and cable. I used a teflon infused cable and new Shimano housing. This greatly improved the situation. The question remains if there was a defect in the original cable or housing that was missed or is there a better combination of components that Co-Motion could provide to allow for proper rear derailleur shifting? We did test ride several tandems at the dealer before deciding on our purchase. The only bike that did not have rear shifting issues was a bike with Di2 electronic shifting. At the time I thought it was due to cable stretch and adjustment issues. Now I'm not so sure.

Another note on the gearing. The bike comes with 52, 39, & 30 tooth chainrings and a 11-32 cassette. When we tour and are going over mountain passes, it would be nice to have a lower gear.

The carbon fork that comes with the Carrera have wide fork blades and a tapered steerer. It is obvious that this fork is meant to take the punishment that a tandem can dish out. I do have a concern about the carbon dropouts. It appears to have the same thickness and size as the carbon fork as on my single bike. I'm not sure if carbon is a good choice for dropouts. The serrated texture of the hub end and skewer will slowly file away the carbon material of the dropout every time the wheel is removed and inserted. Tandems tend to be around for a longer period of time than a single bike. I suspect the front wheel may also come off more often for transport. I'm wondering if there is a minimum thickness specification of the dropout which will require the fork to be replaced?

After 3 months of use, we had issues with the fork. The carbon cracked in the dropout along the lawyer lips. After contacting Co-Motion about this issue, they provided a pre-paid shipping label to ship the fork to them so they could assess the failure. They determined that this was not a defect and was due to removing the front wheel or placing into a car rack with excessive force (we disagree on this). Co-Motion stated that the broken tab could be epoxied back in place and they would ship the fork back to us at no charge. Personally I feel that the fork is an integral part of bicycle safety and that this is an unacceptable solution. Furthermore this broken fork has prevented us from riding our less than 3 month old tandem for weeks (actually well over a month) during prime summertime riding conditions. As a goodwill gesture, Co-Motion did allowed us to purchase a replacement fork at dealer cost. I could not purchase a replacement T390 carbon fork since I believe it has a design flaw (either metal dropouts or an all carbon dropout with a 15mm through axle skewer would correct this) and this delicate fork would be broken again in a few months. I choose to replace with a steel (Speedster) fork. A carefully crafted e-mail to the dealer that resulted in a goodwill gesture by the dealer to pay for the steel fork. Since Co-Motion has such a good reputation, I'm quite surprised, shocked, and disappointed by their response. Co-Motion does not directly manufacture the carbon forks, but they have an OEM company in Taiwan manufacture it. I suspect that Co-Motion will change the design of this carbon fork in the future that will address this issue.

Based on our experience, I have two recommendations for purchasing a tandem.
1)Consider purchase the tandem from a local bike shop that you trust. I think tandems are likely to have more setup issues than a single bike (this was definitely the case for us – there are more issues than what is discussed here). The issues are more than adjustments and may require specialty tools and component knowledge. It was unfortunate that the dealer was 1.5 hour drive away, but the dealer did not help the situation by not providing us with assurance in their mechanical ability. When discussing some of the issues with Co-Motion resulted in a statement “This is a dealer issue. It is unfortunate that your dealer isn't closer so you can take the bike to them and make them fix it.”
2)I'm going to question the use of carbon on critical tandem specific parts, especially on items that cannot be purchased at a bike shop or online. In the case of the fork, there are three advantages of this material over a steel fork: weight, vibration absorption, and handling. I believe that all three advantages are minimal compared to on a single bike. The weight difference between our previous tandem (Burley Rumba) and the Co-Motion Carrera is ~10 pounds. On our typical routes, it is difficult to see a definitive improvement in time. The small improvement in time is lost in the noise of other factors such as temperature, wind, traffic, and if both captain and stoker are having a good day. The vibration absorption advantage of the fork is minimal because the stoker is the rider that has the roughest ride on a tandem.
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Old 10-04-14, 10:11 PM
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B. Carfree
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That was a very helpful review. Great detail.

It is always unfortunate when things go wrong and manufacturers and dealers don't step up and do the right thing. Considering the nature of fork failure type crashes (which appear to be thankfully quite rare), I don't blame you for not accepting a repair or even paying for a replacement.
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Old 10-05-14, 06:39 AM
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Thanks for the detailed review. We have sold our coupled speedster and we are planning another purchase. Our last three bikes (a tandem and two singles) have been purchased directly from the builders. They were all assembled directly in the shop, with no dealer in the middle. Several thousand miles with no issues on three bikes. Each of the two tandems we purchased through dealers had serious problems in the first 100 kilometers. I know this is a small sample size, but we'll continue to work directly with the builders whenever we can. Good luck getting the fork sorted out.
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Old 10-06-14, 11:04 AM
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Good info to share but it reads more as a listing of ownership issues. For a review I would want to add some riding impressions and comparisons. I cannot tell if you like the bike?

The way these bikes are sold does irk me too. I bought from a dealer when I would have rather bought from Co-Motion directly. I honestly cannot say that the dealer added anything to the process. I do know I was very frustrated to have to adjust derailleurs on my first or second ride and expected this would have been dealt with correctly by the dealer (cable conformance/stretch is likely the issue which would have warranted an informative comment). My dealer is no longer in business, fortunately I am more comfortable doing my own work than taking it to a shop.
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Old 10-06-14, 11:18 AM
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Thanks for the write up. We test rode a Co-Mo Robusta this spring and were impressed with it compared to our Santana Scandium. The brakes seemed to be less impressive when compared to our hydraulic Maguras on our Ventana mountain tandem (obviously!), and even to our Santana's upgraded Cane Creek Direct Curve v-brakes. I chalked it up to the possibility that they were glazed and/or not properly bedded in. I'm still on the fence as to whether disk's are all that necessary or worth the balance of advantages/drawbacks. It also had the Rolf wheels with 28 Gators which is a "no go" on San Diego's post-apocalyptic road surfaces.

I would be leery of carbon dropouts on a tandem fork, too. Mostly because the first thing I do is file off those stupid retaining lips. I'd be less than enthusiastic about doing such to CF. Dropouts are the site of major wear and tear, no matter how daintily you treat them. [retrogrouch]Why, I remember when dropouts were properly made of chrome plated steel[/retrogrouch]. Our Santana at least has metal down there. But the steering tube is, unfortunately, plastic. It seems quite heavy duty in the Santana over-engineered sense, but who knows. As you have no doubt discovered, larger cross-section tires do more for front-end ride quality than saving 8 oz on a fork. I think you made a good call on getting the fork swapped for their steel version, Why worry?

For lower gears, I would suggest getting a cassette with a 36-tooth big cog and possibly getting a 28-tooth granny ring. Front up-shifting suffers somewhat with the smaller granny. If you only need it occasionally, it's easy to swap out before a trip where you know you may need to shave off those extra gear inches.
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Old 10-06-14, 04:55 PM
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From one newbie to another: welcome to the forum. As you can see, I live near Nederland. We may have seen each other on the road.

Bob
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Old 10-06-14, 11:35 PM
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Thanks for your thorough review. Interested to hear more about your 11 speed shifting issues - is it fully resolved or must you constantly tweak it?
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Old 10-07-14, 10:57 AM
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The only rear shifting issue we've had on our Speedster was when I accidentally used a piece of brake housing for that final section before the RD. We have gotten the nicest shifting by using Alligator housing between the brifters and front braze-ons and Jagwire smooth cable inside their plastic sleeves which run inside the Alligator and as far as the BB cable guides.

We run a 26T granny ring and 12-34 in back. The 26-39 shift works fine with our FD. YMMV.

We have a carbon WoundUp fork, now 11 years old, still perfect.

I know I'm not in the majority, but after following vehicles with tandems on roof racks, it just doesn't seem like a good idea. We always put our bike in the car, a Subaru Imprezza. In the winter, when we need full coverage fenders, we put it in our pickup with a canopy.

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Old 10-07-14, 12:15 PM
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Originally Posted by dstang12 View Post
Since Co-Motion has such a good reputation, I'm quite surprised, shocked, and disappointed by their response.
I've been mulling this over for a few days now. I live in Eugene just a few miles from Co-Motion. However, when I bought my last tandem I steered clear of them. A big part of why I went elsewhere is that Co-Motion is prone to selling the newest-latest-greatest without appearing to fully understand what the pros and cons are. Their fork design/failure and proposed solution are examples of this. (I shudder at the thought of fork failure on a tandem.) Their products seem prone to just such malfunctions as you encountered. Often, they step up and handle the issues properly, but they don't have a formal policy that binds them to doing that and that bothers me. I guess my approach to bikes and to standing behind one's product are not in synch with Co-Motion.

Interestingly, even though I am seeing an increasing number of other tandems on the road locally, I'm not seeing any Co-Motions. I don't know why this is. I'm seeing some Calfees, Santanas and Burleys, which kind of spans the price range, but no Co-Motions in spite of the fact that Co-Mo generously supports every cycling event that comes up.
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Old 10-07-14, 12:19 PM
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Originally Posted by Carbonfiberboy View Post
In the winter, when we need full coverage fenders...
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Old 10-07-14, 02:08 PM
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>"after 3 months of use, we had issues with the fork. The carbon cracked in the dropout along the lawyer lips."

I'm curious what you exactly mean by this. Did the dropout itself crack, or did the little ridge ("lawyer lip") crack/chip? If it's just the lip, I can see that not being too big of a deal, as they aren't integral to the dropout. I can't imagine that Co-Motion would have offered to epoxy and send the fork back for use if there was any sort of structural issues. The liability potential would be huge (in fact, I'm surprised they offered to do anything to it).

My Santana Cabrio triplet came with a carbon fork. I know everyone says carbon forks are as strong as steel, etc., etc., and I'm certain Santana vetted the design specs against possible loads, but I just didn't feel comfortable having a carbon fork on a three seater bike that could carry 400-500 pounds of riders depending who was on the bike. I guess it's just a mental thing. I swapped it out for a steel fork, but kept the carbon for when we ride the bike as a tandem (which so far has been never, but maybe someday...).
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Old 10-07-14, 06:26 PM
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Concerning the carbon dropouts, the only fork I've had to replace was the OEM fork on my Trek 5900 single. This was a relatively early generation carbon fork with aluminum fork tips. After many years the adhesive between tips and the carbon legs started to fail.

Trek replaced the fork with a current product - all carbon.

YMMV.
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Old 10-07-14, 11:04 PM
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Thanks for the review dstang12.

Sorry to hear about your issues with the fork and understand your decision to move away from CF. We have a CF fork on our tandem it performs well and we have had no problems but, for many, peace of mind may be better with steel.

How many times have you taken advantage of the couplers for a trip? This was something we considered but in the end went with a non-coupled frame - I still wonder about it a little.
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Old 10-09-14, 07:53 PM
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Our tandem has a 10 speed cassette in the back. We have gone on a couple dozen rides since replacing the cable & housing. Have not had to re-adjust since the installation so I would say it is resolved. It doesn't shift as crisp as my single bike, but it is adequate.
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Old 10-09-14, 08:08 PM
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The crack takes out more than just the layer tab. It goes into the dropout at ~45 degree angle downward. Your statement about it not being integral to the dropout is the argument that Co-Motion made. Since this is carbon, I was also concerned about internal cracks and stress fractures that can't be seen. I did ask if the fork was x-rayed to verify this. The answer was no.

I'm not an expert in carbon failure analysis. Is x-ray an acceptable method to determine if internal stress fractures exist?
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Old 10-09-14, 08:58 PM
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Sounds like a little bit of buyer remorse on the Carrera, as far as the Co-Motion Carbon T390 Disc fork goes I would say that it's a mid level entry fork with carbon drop outs, Co-Motiom Tandem Elite Carbon Disc fork has alloy drop outs, this fork is supplied on there Macchiato, a little research on your part before purchasing would have given you the opportunity to make a choice for different components as a ad on, you choose to purchase as spec. At that price point. There's no reason your tandem should not have clean crisp derailleur shifting, I would advise using Dura Ace ptfe cables & Dura Ace polymer coated derailleur cables. Shimano 10 speed chains are directional ck. to see if installed correctly. I've found most tandem manufacturers have there employees putting bikes together that will work, but it's the job of your LBS, not so in your case to fine tune the tandem as we'll tuned machine, test ridden with 2 shop employees and only then to be presented, are learn to do it yourself, to your own level of acceptance.

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Old 10-10-14, 06:43 AM
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Originally Posted by Bad1 View Post
Sounds like a little bit of buyer remorse on the Carrera, as far as the Co-Motion Carbon T390 Disc fork goes I would say that it's a mid level entry fork with carbon drop outs, Co-Motiom Tandem Elite Carbon Disc fork has alloy drop outs, this fork is supplied on there Macchiato, a little research on your part before purchasing would have given you the opportunity to make a choice for different components as a ad on, you choose to purchase as spec. At that price point. There's no reason your tandem should not have clean crisp derailleur shifting, I would advise using Dura Ace ptfe cables & Dura Ace polymer coated derailleur cables. Shimano 10 speed chains are directional ck. to see if installed correctly. I've found most tandem manufacturers have there employees putting bikes together that will work, but it's the job of your LBS, not so in your case to fine tune the tandem as we'll tuned machine, test ridden with 2 shop employees and only then to be presented, are learn to do it yourself, to your own level of acceptance.
Where can you procure tandem length Dura Ace ptfe coated cables?
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Old 10-10-14, 10:58 AM
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I used Easy-Split In-line cable Separators to achieve the shifting and performance that I wanted, with the ptfe cables, A little costly but looking at the overall cost of a tandem it's not that much.
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Old 10-10-14, 02:39 PM
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Originally Posted by dstang12 View Post



The crack takes out more than just the layer tab. It goes into the dropout at ~45 degree angle downward. Your statement about it not being integral to the dropout is the argument that Co-Motion made. Since this is carbon, I was also concerned about internal cracks and stress fractures that can't be seen. I did ask if the fork was x-rayed to verify this. The answer was no.

I'm not an expert in carbon failure analysis. Is x-ray an acceptable method to determine if internal stress fractures exist?
Yes, for sure that's more than just the lawyer tab flaking off. I agree that it would give me pause, too. That being said, it's probably fine because the splitting is at the very bottom of the dropout and there is plenty of "meat" left there for the axle. I'd bet this is not such an uncommon thing to see with carbon forks, due to people placing the fork tips on the ground when they have the front wheel off, etc. (not saying you did that). Looking at the dropouts on most of my steel forks, they all pretty much have the paint worn off where the QR clamps and also on the very bottom of the dropout.

I can't imagine most bike manufacturers having an X-ray machine sitting around to check out carbon forks. Pretty big expense and specialized knowledge required to run it. I'm still surprised that Co-Motion told you it was ok to ride... a lot of potential liability doing that. Whether they should have replaced it for free is debatable, as without knowing for sure it appears that it could be attributable to user error.
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Old 10-10-14, 06:28 PM
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Originally Posted by dstang12 View Post



The crack takes out more than just the layer tab. It goes into the dropout at ~45 degree angle downward. Your statement about it not being integral to the dropout is the argument that Co-Motion made. Since this is carbon, I was also concerned about internal cracks and stress fractures that can't be seen. I did ask if the fork was x-rayed to verify this. The answer was no.

I'm not an expert in carbon failure analysis. Is x-ray an acceptable method to determine if internal stress fractures exist?
Looks cosmetic. I look at the integrity of the actual slot the axle goes into. The crack only hits the very end of that slot where there is not direct contact with the axle and thus very little support. I might even wonder if that chip is mostly resin being on the end/corner as it looks to be.

The location of that chip and the scraping on the rear suggest to me that the carbon fork is much more sensitive to handling during wheel install. Appears that you want that axle going in perfect and not banging around to get right.

I would probably "fix" that fork with some thin CA glue from the R/C hobby store. The thin glue wicks into cracks and such extremely well. I would be sure the chip is pressed in tight before hitting it with the glue. Note that this type of CA sets up extremely quickly. I used to build R/C planes with it and you literally held the two pieces together, dribbled some glue on the joint, and bam it was set. It would set your fingers just as well and quickly.

If I was too concerned with erosion of the carbon I might even laminate thin stainless steel at the contact points. Sand some texture on the back side of the metal facing. Do a bit of careful sanding with medium grit paper to give the epoxy something to hang onto. Clean it all good with acetone so no oils whatsoever. Thin layer of glue. Use the wheel as a clamp to squeeze it all together. Inspect regularly
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Old 10-11-14, 12:12 AM
  #21  
twocicle
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Originally Posted by dstang12 View Post



The crack takes out more than just the layer tab. It goes into the dropout at ~45 degree angle downward. Your statement about it not being integral to the dropout is the argument that Co-Motion made. Since this is carbon, I was also concerned about internal cracks and stress fractures that can't be seen. I did ask if the fork was x-rayed to verify this. The answer was no.

I'm not an expert in carbon failure analysis. Is x-ray an acceptable method to determine if internal stress fractures exist?
Looks more like a side shot of a Guppy fish. :/

Jokes aside, I believe it is important to find a good shop you trust and can drop into with any issue and bounce those off the mechanics there. Although I build up, rebuild, rebuild, rebuild (ie: can wrench pretty well), there are occasional issues I come across where my LBS has really helped out. I insist on paying for everything - even though I am on their sponsored team. Gotta support the LBS... no freeloading. The more mechanically savvy a person is, the quicker that person will be in determining whether or not a shop is up to the task. Sometimes unfortunate, but when you purchase from dealers the mfr may require you to work through that same dealer per the warranty wording.

Concerning the Spyre brake, it sounds like a setup issue that an able shop should be able to resolve with simple spacers or alternate adapters, unless as your shop suspects, the frame mount is not aligned correctly. If that is the case, then the mfr should fix it. Likely they will require you to work through the shop where you purchased the tandem. Braking grip can be modified by cleaning or changing out the rotor and/or pads (which are of a standard Shimano type).

Concerning the Gaterskins, not surprised you found the ride harsh. Gaterskins feel as supple as a... Gaterskin. Rather than going with 32mm tires for everyday non-touring riding, I'd suggest getting a better quality tire such as the 4-Season model. These are maybe 25% better feel. Ultimate suppleness in the Schwalbe Ultremo lineup (IMO another 25% more supple), but a bit less puncture resistant. Although I use Conti 4000 tires on our singles, I would not put those on our tandem due to the tread/sidewall transition layup and too many reports of blow offs from tandem teams.

Last edited by twocicle; 10-11-14 at 12:23 PM.
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Old 10-11-14, 08:41 AM
  #22  
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Co-motion's offer to repair the fork with epoxy free of charge, or let you buy a replacement at a discount sounds fair to me. I agree with your sentiments about carbon drop-outs though. If the tips are so fragile, maybe they should have designed in metal scuff plates at the ends.

Personally, I avoid going through a local dealer, and have purchased two tandems directly from the manufacturer and done the final assembly myself. There are a limited number of maintenance issues I would go to the shop for. Maybe 2 or 3 over 15 years? These machines are really not very complicated. However, I understand and respect that many are not comfortable taking a wrench to their bike.
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Old 10-11-14, 06:40 PM
  #23  
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Owned and rode a 1993 full custom Co-Mo tandem for 'only' 56,000 miles. Great tandem and great folks to work with.
Currently own and ride a 2003 Zona full carbon custom tandem with c/f Alpha Q X-2 fork. 40,000 miles on that tandem and no issues with frame/fork and only fair wear on componentry.
The latest and lightest gee-whiz stuff can be problematic. Have test ridden many components that were in development stage; some never made it to market.
Tried the first D/A 3-chainring brifters; after 3,000 miles gave up on 'em as the triple was troublesome and seldom got clean shifts.
Also tested the first Di2 electronic shifting. Great when it was working, but failed miserably after 1,800 miles of usage in the middle of a hill climb. So much for recharging and redundant warning system that never did work!
Test rode one of the first Gates carbon belt drives; nice but quite pricey at the time; never do get chain tattoos on legs as I never oil my chains (been using the hot wax method since the '70s).
Used disc brakes (front and rear) on a test tandem. Great stopping power, however consider them a bit of overkill and yes, have seen folks spray water on their disc brakes to cool them and also having warping and melting of plastic parts.
Back to using triple front and 9 speed cassette with bar end shifters. May be 'old' technology but works great!
Just our input/actual experience.
Pedal on!
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Old 11-13-14, 07:00 PM
  #24  
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Just a note. Skewers are only suppose to leave a small imprint in the palm of your hand when tightened properly
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Old 11-13-14, 11:54 PM
  #25  
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Having done some layup work, I'd say the apparently cracked fork end is a factory defect. What probably happened is that for some reason the fiber layup didn't come out quite right and was a bit short on the bottom or perhaps had an air bubble. They probably prepped it and puttied it, then faired it in so you couldn't tell and painted it. So that's the reason it cracked so easily and probably did happen when using the rack. That's also the reason CoMo is a bit lax about it: it's not structural. It cracked where the fibers end. My guess is that there is no further damage and the fork is perfectly safe. You might try to pull the broken parts completely off and see if I'm right about this.

Probably a carbon dropout fork is stronger and safer than an aluminum dropout carbon fork. Bonding epoxy to aluminum is always a tricky business. Lots to go wrong there: the basic bond, shock, and corrosion in the aluminum. Continuous carbon fibers are really a better way to go as long as the design takes into account the properties of a carbon epoxy layup, which this design appears to do.

That said, we've never had a problem with our 10 y.o. carbon/aluminum WoundUp fork.
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