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Tandem Cycling A bicycle built for two. Want to find out more about this wonderful world of tandems? Check out this forum to talk with other tandem enthusiasts. Captains and stokers welcome!

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Old 08-31-05, 09:27 AM   #1
cornucopia72
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Broken handlebars; Is it a common occurence?

About three months ago and while in a pace line, a friend and fellow rider broke his handlebar. We were going under 25 MPH but since he was on the drops, when the handlebars broke his chest hit the stem and he and the rider behind him went down. He broke his collar bone and has not returned to the road since. After this incident there was a lot of talk about the need of replacing the handlebars at least every two years. We felt confident since our Santana tandem was less than a year old.

Well, yesterday, while standing on a moderate climb, I found myself holding to a loose piece of pipe on the left side of the bars. Thanks to the quick reaction of my stoker and the very slow speed we were traveling at, we did not go down. We were 20 miles away from our truck and the nearest town. We searched for a piece of wood or something that we could stick inside the pipe. Then my stoker suggested using the pump. We moved the broken area to the middle of the stem, took the tape out of the handlebars and with it braced the bars with the pump. It felt so sturdy that we continued our planned ride but instead of 100 miles we only did 80.

Yesterday we wrote to the handlebar manufacturer to ask if they would replace it. But we were thinking that maybe we want to go with something a little sturdier. How common is for handlebars to brake on tandems? Any suggestions as to how we could minimize the possibility of a problem?
Thanks
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Old 08-31-05, 05:51 PM   #2
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Glad no crash occurred! Have heard of only a couple handlebars breaking on any road bike.
Have used bars on 3 of our tandems for over 50,000+ miles . . . all these bars were alloy. One bar was even drilled out to run bar-end cables internally!
Currently using c/f bars for both stoker and pilot with about 8,000+ on the odo . . . so far so good.
Good thinking/handling of stoker/pilot saved the day with a jury-rigged pump as a bar!
Manufacturer should be sent the busted bar and approximate mileage and be willing to send a new/upgraded one gratis.
Pedal on TWOgether!
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Old 09-01-05, 05:48 AM   #3
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This is a normal racing event unfortunately, given teh penchant for feather-light equipment. You don't give the make and model of the bars; certaily if you're using a pair of Deda 215s or some other real light Al bars, they may fatigue and break under the added load of a tandem. Or poorly made carbon (I did not use the word cheap, a lot of expensive carbon is poorly made); or good carbon with the wrong stem clamp or clamped incorrectly. I have Deda 330s stock on my bike and have yet to replace them for this reason. I was hoping someone would have data about what "weight" bar is necessary for tandem handling and safety. My stoker now has a set of ITM 260s but she ain't steering. A stout set of bars shouldn't need routine replacement: airplane frames are aluminum and last for a generation. But if you go for real light weight bars they won't last. Ask yourself if saving weight on your handlebars makes sense. In racing, the classic is "do you want to save weight with your brakes?"; here, the bars would seem a critical component which should be viewed safety-first. Everyone here seems to get that brakes need to do what they're designed to do. Bars are the same....
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Old 09-01-05, 07:33 AM   #4
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Originally Posted by ElRey
You don't give the make and model of the bars........
The bars are Modino Q-race 26mm 44cm. I am 6'3", 185 lbs and my stoker is 5'5", 147 lbs. We do not race but do ride hard and go up steep hills often. We defenitely do not want to save wt. on the bars. Any recomendations on thickness and size? Is it safe to assume that a heavier bar would be sturdier? Does c/f bars fail sudenly, the same as aluminum?

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Old 09-01-05, 07:36 AM   #5
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Originally Posted by cornucopia72
We felt confident since our Santana tandem was less than a year old. Well, yesterday, while standing on a moderate climb, I found myself holding to a loose piece of pipe on the left side of the bars.
Assuming these were the stock bars, did you report the failure to Santana?

If they weren't the stock bars, whose were they and what model?

Bars break, but there's usually a reason...

- track racing places very high demands on bars; a lousy place for SL models
- strong sprinters who race should consider updating bars and stems every season
- other racers and folks who put 10s of thousand of miles on each season under hard use are far more likely to put enough fatigue into the bars and stems to warrant periodic replacement
- very large riders should regularly inspect their bars, stems, as well as seatposts for indications of accelerated wear and consider periodic replacement consistent with how much they ride the bikes
- score marks from bars twisting in the stem clamp or from razor blades used to cut handlebar tape ends near the stem that are, in effect, stress risers which weaken the bars
- prior crashes or other impacts against the bars (driving into a garage with the bike on top of the car) where it was assumed there was no damage
- product defects
- the use of SL or carbon bars with the wrong type of stem (4 bolt vs. 2 bolt)
- over-torqing the stem clamps
- the use of superlightweight components by riders who are anything but superlightweight

However, the vast majority of handlebars on the average cyclists handlebars that have been properly installed are usually good for many thousands of miles of use by most average cyclists. In fact, if I exclude racers who have snapped handlebars, the numer of cracked stems and seatposts actually become a more frequent occurance, particular stems of late: two stems along in the last year among our friends, one a hard core team on a tandem with well over 10k miles (hairline crack under the stem neck) and another strong but average sized rider who logs 2k miles a year or so on a 3 year old bike (also a hairline crack).
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Old 09-01-05, 12:03 PM   #6
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I did a web search on Modino handlebars and came up empty, so can't talk about them particularly. Not sure I agree that Santana is the place to complain, maybe the shop you bought from, but then again I don't know Santana. Maybe they make these bars in-houese. I can say that ITM bars have been very durable for me, and Ritcheys seem to be OK but not as good. Deda gear hasn't worked out well for me- light but fragile- but the 330s on my Cdale are heavy eonough I'm leaving them for now. Profile = horrible, avoid like the plague (I do have a set of Profile carbon aerobars on my tandem but they don't really take much load... sort of like arms on a chair). Of course, the weight and engineering may be as important as brand for this purpose; triple butted, 195 gram 7075 Al bars don't seem like they'd make sense when you're steering 400lbs of bike/rider. I have a set of Kestrel carbon bars (not the SL variety) and they seem pretty strong. BUt given the stress on a tandem bar I don't know I'd want carbon... 2 vs. 4 bolt stem faceplates for carbon bars is a goodly part of, but not the entire, story: Easton's top-of-the-line stem (which I use on my Kestrel bars) has a two bolt faceplate but the faceplate is very wide and has a curved contact patch- distributes the load across more fibers so they say. My best recommendation, if a gun was to my head, wold be the ITM 260 in a correct size. Since you're a big dude, I'd gues that's a 46cm. I ride 44s and am only 6'.
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Old 09-01-05, 12:26 PM   #7
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I'm guessing what he meant was "Modolo" Q-Race and, if memory serves, Santana does use Modolo bars on their tandems. Again, from what I recall, these are pretty beefy (300+ gram) T6 alloy handlebars. For comparison purposes, our road tandems and my half bike use 3T Prima bars which weigh in at 220 grams and at least one set have more than 20k miles of use. I'm about 170lbs but don't have a massive sprint.

BTW, one of the best reasons to let Santana know is so that they can be alert for any similar reported failures which could be indicative of a defective production lot from their supplier or something else that they may need to run to ground, e.g., unqualified mechanics doing the assembly, stem incompatibility, or any one of a couple of things.

Also, as I've mentioned to others who have shared problems or issues that they have with their tandems (or that others have shared with them), it's only fair to give the manufacturer or the business that sold the bike to you an opportunity to make things right before deciding to alert the masses. After all, part of what you pay for with new products like tandems is warranty and factory support. You might as well take advantage of it. And, given that this failure could have resulted in serious injury, if the bar was defective or mis-installed I'm sure all the parties concerned will be glad that you aren't having your lawyer make the calls.

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Old 09-01-05, 01:28 PM   #8
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It is Modolo Q-race... sorry about that. At tandemgeek's recomendation I called Santana and they are going to replace the bars. I am glad I called them because it turned out that the bars are 25.4 and not 26 as I had assumed. I was also thinking on going to size 46 for enhanced control but decided against that because of fear of putting more stress on the bars due to laverage.
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Old 09-01-05, 09:59 PM   #9
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I've snapped a Profile Hammer DB bar and went down. Thankfully, I was crossing a street on a Rails-to-Trails route and was only at 10-12 MPH at the time on my solo.

Since then, all my road bikes and tandem are / will be with carbon bars now (9 total) - 2 are still alloy (ITM Millennium and Deda Newton) but I have a 26.0 and 31.7 carbon, respectively, in the waiting when its time to replace the bar tape on each.

I think much of it depands on the clamp style (1-, 2-, 3-, or 4-bolt faceplate / clamp) and whether you've "spun" them in the clamp during setup or otherwise. The slight scratches and creases created by the edges when rotating the bar in the clamp is enough to score and slowly weaken the bar.

A 25.4 in a 26.0 clamp will also be cause for concern - too tight and not spherical enough to hold the bar at equal pressure on all sides. A 25.8 / 26.0 or 31.7 / 31.8 pairing is OK, but the extra 0.6 will make the clamping area more ovalized.
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Old 09-02-05, 07:50 AM   #10
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MOdolo Q Race bars are on sale at Nashbar right now for $24. Personally, I would never think of using a $24 set of bars on a single. I'd recommend upgrading your bars to a major brand.
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Old 09-02-05, 09:20 AM   #11
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Quote:
Originally Posted by ElRey
MOdolo Q Race bars are on sale at Nashbar right now for $24. Personally, I would never think of using a $24 set of bars on a single. I'd recommend upgrading your bars to a major brand.
Modolo IS a major brand and an OEM supplier to many companies like Santana....

If you're insecure about an affordable, durable but not superlightweight bar that has been produced for many, many years Modolo also sells a $300 carbon bar through Excel, the Competitive Cyclist, and some other more pricey retailers. It would be interesting to know what caused this particular bar to fail and hopefully Santana has asked our friend to return it to them so they or perhaps Modolo can inspect the failure point.
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Old 09-02-05, 10:17 AM   #12
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Yes, I was just about to come back here and recant... T'geek beat me to it. MOdolo has a good rep. I don't know anybody who uses them, but that's on me not them. And the Q Race would seem a good choice from their line for a tandem.
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Old 09-02-05, 10:50 AM   #13
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I also saw the Modolo Q-race in Nashbar for $24.00 but it was 26mm and not 1". The Santana Rep, Gerrard sp??, was most helpful. He asked me to send the bars back. Since we are training for the Bass Lake / Powerhouse double century I asked him to send the new bars right way. I need to call him back with the tandem serial number and after he provides me with a RAN, I will send the bars back. I'll make sure to ask what do they think about the cause for the failure.
I also asked Gerrard about CF handlebars. He told me that they are working with the manufactures and that soon there will be a tandem specific oversize stem/bar CF option.
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Old 09-02-05, 08:50 PM   #14
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I have a little theory about this issue..

on a typical single bike the bars suffer from many torque loads, not only from body sopport and pure downwards presure but the Upwards motion when you are springting or climping, anyway on a single bike the whole bike kind of rocks side to side when this loads are being transfer diminishing the stress on the components, on a tandem specially if the "Couple" is a little Off face, out of sich whatever you want to call it , those loads are going to be magnified in a big way reason why bars are more prone to twist, bend and break,, just take a look at a stocker stem and seatpost and how sometimes they are misaling, twist and bend do to the effords of the stocker to "Control" the bike.

well i hope this make sense,,believe in moments like this (more than ussual) i wish my Ingles was a little better since the concepts are a little complex to explain..
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Old 09-08-05, 02:32 PM   #15
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I have broken only one handlebar in years of riding. But since it can lead to such a bad accident, I do try to replace them at least once every 3 years on bikes that I ride often.
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Old 09-08-05, 03:24 PM   #16
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Up until two weeks ago, I had heard of bars failing, but never witnessed it first hand. Well a rider we were riding with, on his single bike, was climbing one of the moderate inclines we have here in Florida when his handlebars broke. They broke right at the stem clamp. They were TTT Forma bars which are not exceedingly light.

This rider is a tall strong guy that is probably at least 225 pounds and typically stands and pulls on his bars when he climbs. I'd say that for a guy like him, it would be a good idea to change his bars every 10,000 to 15,000 miles. For a smaller rider or one that does not apply large cyclical loads on his bars, that replacement would be needed on much longer intervals. However defining that interval is a difficult thing. Unlike steel or titanium, all aluminum parts will fail from cyclical strain in time - predicting just how many cycles will be necessary to cause a fatigue failure is the hard part (and probably frought with legal liability concerns as well). So everyone is left to make their own estimates and then take their chances.

Too bad there are no steel or Ti bars that I have seen readily available.

BTW, I would think that a cheap handlebar would be safer than an expensive one, simply because the cheaper bars are heavier and use a thicker cross section of aluminum. When you buy a more expensive bar you are paying for extra butting and swaging, designed to remove any superfluous weight.
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Old 11-02-05, 10:50 AM   #17
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It would be interesting to know what caused this particular bar to fail and hopefully Santana has asked our friend to return it to them so they or perhaps Modolo can inspect the failure point.
Santana sent us new bars. My understanding was that Santana will cover the cost of the bars and I would have to pay for express shipping (we needed the bars right away for an upcoming century ride). We sent the broken bars to Santana. A few days later Santana called us and said that they will not cover the cost of the bars because they found out that the bars were improperly attached to the stem (over-tightened). When I mentioned to Bill that the Tandem, which we purchased from Precision Tandems, came with the bars already attached to the stem, Bill said that he would look into that. We are happy to report that Santana paid not only for the bars but also from the express shipping. We do not know if Santana in turn charged Precision Tandems....

In summary the bars failed because they were over-tightened... Santana has excellent customer service.
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Old 11-02-05, 11:31 AM   #18
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dude, did it take 2 months to resolve this?
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Old 11-02-05, 02:29 PM   #19
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Somewhere up there was a discussion of carbon fiber vs. Aluminum...

Aluminum has a tendency to bend when it is highly stressed, which leads to small cracks forming and eventual complete failure. Pinching of the bar at the stem is a good possibility, since it really does take a lot of work to bend an AL bar, even a cheap one.

Carbon fiber is a different animal. It's much more resilient than AL so a well-built bar will handle more low-amplitude stress than AL without deforming. The only thing is that if carbon fiber is stressed to its VERY HIGH breaking point, it will fail catastrophically, i.e. explode.

I used a Race Face carbon bar on my mtn bike back when I weighed about 220#, and never had a problem with it. The key is making sure that you're buying from a good carbon fiber manufacturer.
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Old 11-02-05, 04:08 PM   #20
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One of the things I noticed on our Dale MT tandem was that the pilots bars were flexing a bit. I did not trust them as We are a bit aggressive on our offroad jaunts, and replaced them with Downhill spec Riser bars. These are heavy, and pretty thick aswell. The pilots bar I put on to my position as stoker as they were more comfortable, a bit wider and a slight rise. 6 months later- the stokers bars snapped, and not at the centre either. It was 1" out from the centre bulge.

Mind you, as I have said we are aggresive riders, but the thought of the pilots bars snapping is not something that I want to contemplate. Since then, all parts upgraded or replaced on the Dale, have always been of Downhill quality parts. Not necessarily heavy parts, but the quality is there and so is the high price.
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Old 11-02-05, 04:49 PM   #21
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dude, did it take 2 months to resolve this?
No, they sent the bars right away. I was wating for my credit card statement to show the express shipping charge. Santana did not charge me for anything.
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Old 11-02-05, 05:10 PM   #22
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We've got titanium riser bars on our tandem. No worries at all. Fatigue would be a concern with aluminum, as they're 27" wide, mine have bar ends, and they get wrestled a lot.
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