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-   -   Looking for an Alpha Q X2 Tandem Fork (https://www.bikeforums.net/tandem-cycling/623672-looking-alpha-q-x2-tandem-fork.html)

ginkeler 02-21-10 11:41 PM

Looking for an Alpha Q X2 Tandem Fork
 
Help....I'm looking for an Alpha Q X2 Tandem Fork....anyone know of a source?

TandemGeek 02-21-10 11:49 PM

Calfee may still have some, but I'm not sure if they're selling them for aftermarket buyers. You'd need to contact them to find out. If they aren't selling them ask them for a recommended replacement, as they'll know what the next best thing is... or when the next best thing might be available as Calfee was working on an in-house solution to the demise of Alpha Q.

Precision Tandems still lists them but the prices are over the top; probably best to call around to some of the specialty tandem dealers, e.g., Tandems East, Mt.Airy Cycles, Crank-2 tandems, Tandems Ltd, Tandem Cyclerworks of Colorado, Gold Coast Tandems & Recumbents to see if they have any on hand.

It's really tough finding them as they were discontinued last summer and there just weren't a lot in the pipeline at the time.

Butcher 02-24-10 10:21 PM

There's one on eBay.

Al Bundy 02-24-10 10:50 PM

http://www.bikeforums.net/showthread...pha+car+q+fork

I had a car accident a while back and couldnt find one
all remaining stock is with Calfee and Como - bought direct from True Temper
May be some odd ones around and at one point Mel (TandemsEast) said he had one.
The Edge might be the ticket if you lose the ebay auction.

ginkeler 02-25-10 11:40 PM

Thanks....Already contacted Calfee, Co-mo....they have a very limited supply and will not sell them w/o including a frame....they don't have a sure thing lined up for anytime soon. They both claim there going to be dead in the water soon....I've contacted most of these shops you noted and they have nothing...some didn't even know that these forks were out of production.

ginkeler 02-25-10 11:42 PM

Used, cut-down with the plug glued in.....mmmmm

ginkeler 02-25-10 11:49 PM

I spoke to Mel...at first he said he had one and then when it came down to it, nothing??? The Edge forks are real nice but the max weight is too low for 2 guys..... My fame builder is trying to work with them to make a fork????

Ritterview 02-26-10 12:46 AM


Originally Posted by ginkeler (Post 10452923)
The Edge forks are real nice but the max weight is too low for 2 guys..... My fame builder is trying to work with them to make a fork????

The Edge 2.0 fork doesn't have a weight limit, however it does specify:


Warning:Edge Composites forks are not approved for tandem bicycle use.
The Alpha Q fork weighs 375 grams and the Edge 2.0 350 grams. Edge components in general, and the Edge fork in particular, are reputed very stiff and robust for their weight. So, it isn't known that the Alpha Q is more tandem capable than the Edge, though it has a tandem designation.

Edge knows that the tandem market is interested in its forks, but it may not think the tandem market worthwhile to test the 2.0 for that application.

born2pdl 02-26-10 09:36 AM

Bontrager tandem carbon forks with Al steer tubes were being closed out a year or two back. Maybe there are some still available. We replaced the steel fork on our 2004 Trek T2000 with one and I like its quicker but not twitchy handling. Weighs lots less than the steel fork, more than the alpha q. I'm glad I got it instead on the alpha q. I ride withour worrying about it at all, but would have always wondered if my 375gm fork were going to fail during an unexpected event.

TandemGeek 02-26-10 10:57 AM


Originally Posted by born2pdl (Post 10454087)
but would have always wondered if my 375gm fork were going to fail during an unexpected event.

Have you received any first-hand or even second-hand reports of unexpected catastrophic carbon fork failures on tandems... Alpha Q or otherwise?

I'm not talking about carbon forks that develop stress cracks and have to be replaced or forks that broke as a result of a crash caused by something else, but an honest-to-goodness "just riding along and my tandem-rated carbon fork failed without warning"?

Ritterview 02-27-10 01:39 AM

The site doesn't indicate they are out of stock:

Alpha Q X2 Carbon Tandem Fork

Ritterview 02-28-10 01:05 AM

Co-Motion is using an Edge fork on this bike, from NAHBS. The Alpha Q is still listed on the website as the Macchiato's fork, but perhaps Co-Motion has made the switch. Co-Motion's imprimatur would provide some confidence in using the Edge 2.0 on a tandem.

http://farm5.static.flickr.com/4030/...4aff3c6282.jpg

Paketa now lists the Easton EC90 SL as its high end fork.

mrfish 03-01-10 10:26 AM

Most people I know think that the EC90 SLX is marginal on a single bike and opt for the SL as a stiffer alternative. SL on a tandem...Hmmm...

Still, to put all this single bike fork on a tandem stuff in perspective:
1) European safety standards have increased significantly in the last few years, without much reason as forks didn't previously fail through JRA use, so it's true to say that single forks are over-specified for most people, and now most cater to worst case scenarios of very heavy riders.
2) If a man weighing 140kg or whatever can ride a fork comfortably on a single bike, why should a man and a woman weighing 75kg plus 60kg on a tandem stress the fork any differently? My Engineering degree says the stresses experienced by the fork are the same. Basic mechanics suggests that the forces can only act on the fork through the headset bearings, wheel spindle and the reaction force from the tyre. As long as the total mass of the tandem and the proportion of weight through the front wheel is the same, the fork has no idea whether it's on a tandem or not. If the tandem riders ride in the same way as the rider on the single bike, then the forces must be the same. Note this assumes that the head tubes are equally stiff, which I think is a fair assumption.
3) Quite a few people have run cyclocross forks on road tandems without big issues reported (although this is like saying a lot of people do base jumping and you don't hear much about the deaths)

My personal view is thus moving towards it being reasonable for light teams to use high quality single bike forks on a tandem. I would agree that safety margins are lower than usual, so it would be prudent to install and inspect the fork periodically to avoid stupid risks. Question remains what constitutes a light team - is it 100kg, 150kg or 200kg?

It would be interesting if someone familiar with bike stress analysis and tandem / single bike impact standards could comment.

Dean V 03-01-10 10:57 AM

As long as your front brake was powerful enough you could definitely put more load under braking on a tandem than a heavily loaded single, due to the longer wheelbase. There is also those bumps and pot holes that you don't see in time. On a single you quite often have time to lift the front wheel, with the tandem you just have to plough on through.

WebsterBikeMan 03-01-10 10:58 AM


Originally Posted by mrfish (Post 10465545)
2) If a man weighing 140kg or whatever can ride a fork comfortably on a single bike, why should a man and a woman weighing 75kg plus 60kg on a tandem stress the fork any differently? My Engineering degree says the stresses experienced by the fork are the same. Basic mechanics suggests that the forces can only act on the fork through the headset bearings, wheel spindle and the reaction force from the tyre. As long as the total mass of the tandem and the proportion of weight through the front wheel is the same, the fork has no idea whether it's on a tandem or not.

My physics degree begs to differ :-)
The proportion of weight through the front wheel is not the same. On my single, I'm putting substantially more weight on the rear wheel (70-30? 65/45?), while on our tandem, we're about 45-55, as I recall - 45% front, 55% rear.

But your basic arguments still holds. I can find the force on my front wheel - put a scale under the front wheel with the rear held in a trainer, and the wheels level. Put both riders on the bike and read the scale (with binoculars if necessary). A single bike fork rated for a single rider who puts the same force on the front wheel - whatever the weight distribution - should have the same impact on the fork.

TandemGeek 03-01-10 11:21 AM


Originally Posted by mrfish (Post 10465545)
If a man weighing 140kg or whatever can ride a fork comfortably on a single bike, why should a man and a woman weighing 75kg plus 60kg on a tandem stress the fork any differently?

None in the grand scheme of things if we assume max braking or an impact with a road obscacle are the thresholds, but the number of cyclists that weigh in excess of specific fork limits pale in comparison to the number of tandem teams who would. For reference and while not truly scientific, Question #6 of my Winter '05 Tandem Survey indicated 63% of the respondents claimed a team weight in excess of 140kg .jpg. Given that most folks understate their weight with about the same frequency in which they over state their average speed there aren't a lot of folks out there that would meet the threshold of a fork limited to about 300lbs. Oh, and don't forget to add in the weight of the tandem as ridden which is typically twice that of a single bike.

So, at least for manufacturers, why should they waste their time and profits certifying forks for tandems that are severly weight limited in terms of the standards used for mass-produced tandem bikes? I want to say that 400lbs - 450lbs is often times cited as the benchmark.

Conversely, since there are so few 'tandem-rated' components available, nothing prevents a lightweight team (noting I would peg lightweight at under 275lbs) from doing their own research to establish which forks are, in fact, rated for enough weight to accommodate the gross weight of their tandem. Again, I have over the years contacted a number of manufacturers to ask those very pointed questions "off the record" with regard to how well-suited a given compoment might be for our lightweight tandem team. Some will speak off the record and make it clearly understood, "you're doing so at your own risk... however..." before sharing if the design limits will accommodate. But, again, for general consumption by the masses, weight-limited components on tandems are just not worth the liability burden for anyone in the business.

WebsterBikeMan 03-01-10 12:24 PM


Originally Posted by TandemGeek (Post 10465763)
Not in the grand scheme of things if we assume max braking

I think this is the key one. At max braking, the rear tire of a single is about to leave the ground, which means the front has force with a forward component of about 0.67g times the mass of the bike plus rider, and downward component 1g times the mass of the bike and rider. (I'm pulling the 0.67g from various web searches). The net force is about 1.2g times the mass of the bike and rider, or 1.2 times the weight of the bike and rider. With a tandem, it's pretty hard to get the rear tire to leave the ground, but estimates of the maximum coefficient of friction between tires and dry road appear (according to that great oracle, the web) to be in the range of 0.7. Which means that you skid first, but just before skidding you're looking at fairly similar forces on the front fork, except that they are in proportion to both riders' plus the heavier bike's weight. The forward component is greater than on a single, and slightly more than in proportion to the total weight. I can't find a good estimate of the downward component, but I can easily put a lower bound on it: we have .45 of our weight downward on the front when there is no braking involved. The upper bound is 1. So long as the the shift puts it above about .75, you're looking at more force on the front fork than the weight of the bike plus the team (.7^2 + .75^2 = 1.05). At any rate it is more than double the static force on the fork when at rest or in constant horizontal motion.

And this is the time when it is most likely to matter.

So if your team plus bike is lighter than the heavy single rider plus bike, you're OK. Otherwise, the argument about weight distribution doesn't help much.

Eddie50 03-01-10 06:07 PM

I have one, its new, never been cut or installed, I bought when I had my cannondale, but I changed tandem and it came with a carbon fork.

I would be willing to sell it, if someone is interested, I am in canada, but sinche its light should not be too expensive.
Just PM me if you have questions.

Bruno

TandemGeek 03-03-10 04:37 PM


Originally Posted by Ritterview (Post 10461081)
...but perhaps Co-Motion has made the switch.

Probably not.

Alpha Q is still their OEM offering and will remain so until their fairly robust in-house supply of X2's is exhausted.

uspspro 03-04-10 09:10 PM

The Alpha Q feels too flexy to me really. I love the Edge 2.0 on my CAAD9 single.

Ritter, let me know how you like it on climbing out of the saddle and most importantly while cornering on speedy descents.

The behemoth steel one on our old Santana might have had too slow of geometry and was more like "driving a truck" but it was sure stiffer than this Alpha Q. If the Edge feels good, I would make the switch.

Ritterview 03-04-10 09:46 PM


Originally Posted by TandemGeek (Post 10476838)
Alpha Q is still [Co-Motion's] OEM offering and will remain so until their fairly robust in-house supply of X2's is exhausted.

I emailed Co-Motion to ask them about the Edge fork on their NAHBS tandem, and to inquire as to their plans with the demise of True-Temper. Their response, which I told them I would share with the BF Tandem Cycling forum:


Originally Posted by Co-Motion
Hello Ritterview,

Thanks for contacting us. I've spoken with Mark Livingood about this, so assumed he would share some info with the group. The Macchiato we had in our booth at the NAHBS show belongs to one of our dealers who installed the Edge fork of his own volition. Edge does not have a tandem-ready fork, although they are one of the manufacturers we have been working with to make a suitable replacement.

We are currently receiving prototypes for testing purposes from 3 different manufacturers. After we run our own tests as well as some third party tests we will have a Co-Motion branded tandem fork. Price, weight, geometry and appearance will be similar to the Alpha Q X2. We have enough X2 forks to last us through May, not for resale, but to outfit the tandems we spec them on. Don't be concerned about us being "dead in the water". We've been working on this project since last fall.

Best regards,

Dwan Shepard

Co-Owner

https://mail.google.com/mail/?ui=2&i....1&disp=emb&zw

Co-Motion Cycles, Inc.
4765 Pacific Avenue
Eugene, OR 97402
541-342-2210

So,
  • The Edge fork on the NAHBS Machiato did not signify a Co-Motion endorsement.
  • Co-Motion is testing forks from 3 manufacturers, one of which is Edge.
  • Co-Motion will pick one of these to market as a Co-Motion fork.
  • They will need a Co-Mo branded fork by May, when they exhaust their supply of Alpha-Q's.

Nice that Co-Motion is working on this, as a new carbon tandem fork is a welcome development.


Sweet Macchiato from NAHBS, nicely equipped with with ZG's, Topolino's and an Edge fork.

http://farm3.static.flickr.com/2711/...cdd941d0cd.jpg

TandemGeek 03-04-10 10:20 PM


Originally Posted by TandemGeek (Post 10476838)
Thanks for contacting us. I've spoken with Mark Livingood about this, so assumed he would share some info with the group.

Which I did to the extent needed to address the basic question, noting our 'discussion' included some additional details that caused the vast majority of the information to carry this caveat, "We'll make an official announcement about this when we've made a final decision and have product ready to ship. So, this info is for your eyes only, please."

Therefore, when I post something like this...


Originally Posted by TandemGeek (Post 10476838)
Probably not.

Alpha Q is still their OEM offering and will remain so until their fairly robust in-house supply of X2's is exhausted.

... it's because I've looked into the matter with the folks who know what's really going-on.

You may also recall this tidbit from January 1st's Bulletin Board:


Originally Posted by TandemGeek (Post 10476838)
Et tu, Alpha Q? For those who may not have notice, Reynolds quietly got out of the carbon fork business a while back so no more Ouzo Pro Tandem forks. In fact, John Slawta of Land Shark cycles apparently bought up a lot of Reynolds' remaining inventory and blew them out on Ebay at about 1/2 price. More recently I've learned that True Temper (aka, Alpha Q) is also exiting the carbon fork market so, again, for those who had tandems built around an Alpha Q X2 tandem fork, replacements may be hard to find as current inventories are exhausted. Now, on the bright side, I have it on good authority that a well-known bicycle design and fabrication house has approached True Temper regarding the possible acquisition of Alpha Q fork technology and tooling. More to follow IF something develops.

No, that was not a reference to Co-Motion. But, as I said, I do my best to share what I can while still respecting confidentiality, so you must sometimes take me at my word on face value.

TandemGeek 03-11-10 02:56 PM


Originally Posted by Ritterview (Post 10457485)
The site doesn't indicate they are out of stock:
Alpha Q X2 Carbon Tandem Fork

They have since flagged the Alpha Q X2 as "This item is backordered" which, it turns out, was also true back on Feb 27th.

However, it does appear as though they do have a source. Probably best to call and speak with someone to get real time information on availability.

The price is definitely right...

TandemGeek 03-16-10 03:32 PM


Originally Posted by TandemGeek (Post 10512492)
However, it does appear as though they do have a source.

Or not.... which is not surprising.

Full disclosure: Frankly, I had a hard time believing Beyond Bikes (or anyone else for that matter) still had X2's in stock at full price, never mind at a 20% discount. So, just for kicks I put one on order. As noted above, the order sat in limbo for a while which seemed to suggest that there really wasn't one in stock that they could use to fulfill the order. When I called to check on the order after several business days had passed as the order sat in limbo the support folks said "It was showing as on-dock"??? Hmmm. Interesting. Well, I decided to let it ride and then on March 11th I receive a notice that it had shipped. Hmmm. Maybe they did find a source?

Well, the X2 showed up today only it wasn't an X2. It was a CX fork carrying a CX designation on the "Made in China" label and elsewhere that the distributor had gone and labeled as an X2. In fact, they went to the trouble of even attaching a label to the fork leg right along side the CX markings and cantilever bosses.

Anyway, it's going back to Beyond Bikes on a call-tag for a full refund. Thankfully, I already have a spare X2 fork so I'm not overly concerned.

Bottom Line: File this one under Too Good To Be True... which is what it seemed to be from the git-go.

Ritterview 03-16-10 04:25 PM


Originally Posted by TandemGeek (Post 10534842)
...So, just for kicks I put one on order.

Wow, that is going above and beyond the call of duty, TG. It would have been cool if you had discovered the the legendary elephant's graveyard of of AlphaQ's, with vast piles of new X2's available at 20% discount.


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