Santana Sweet 16 Rim Crack under normal use
Has anyone else had a Santana Sweet 16 rim crack under normal use? This crack occurred after about 3000 miles on the rear wheel, right side, directly above where a "pushing" spoke enters the rim. The proposed explanation is that the spokes gradually became de-tensioned over time, eventually causing the failure. The crack was discovered immediately after a spoke broke. There is no sure way to tell if the crack developed before or after the spoke breakage. My guess is that the crack was there before the spoke failed.
What have the folks at Santana said? Also, if you don't mind me asking, what's your total team weight and riding style?
I think those wheels carry a 2 year warranty.
The wheels have a 2 yr warranty, but they are 6 months over that.
Santana has stated that the probable root cause for both the crack and the spoke failure was the gradual loosening of the spokes. Although I find this to be a plausible theory, I find it difficult to except that the wheel gave no warning prior to these failures. These wheels performed nearly perfect up until the failures. They were slightly out of true, but not enough to take a wrench to them.
Santana did not (would not) answer my question as to how many of this type crack they have seen. I know that broken spokes are not uncommon on these wheels, but the frequency of cracked rims is unknown. Santana makes a big deal out of having the right spoke tension, as they should. These are high performance wheels and the purchaser should be aware and be willing to “maintain” them…..But Santana never stated, written or verbal, that the wheels require periodic spoke tension maintenance, even though they remain true and trouble free. When asked if my wheels (2 yrs, 6 months old) were built with a “spoke dope” of some kind, the response was that they did not know.
The wheels have about 3000 miles over 3 riding seasons. About half these miles where with a total crew of weight of 170lb Captain, 175lb stoker. The remaining half is with same captain but with a 145lb stoker. The riding style was aggressive with a lot of “off the saddle" climbing on short rollers and steeps. I have 2 other wheel sets that I use around town when I know the road conditions will not be bike wheel friendly. These wheels have never seen trauma. I ride them hard but take good care of them.
My concern is 2 fold. I am about to invest more into these wheels to affect the repair. It is not so much the money as it is the uncertainty of the reliability. If I know that I could have prevented this early failure by periodically checking spoke tension, then I have no issue with that. Also, Santana has recently stated that since they have had such great success with these wheels, they have not only reduced the rim (and hub) weight, but they have also removed the 400lb weight limit.
In general, I would suggest that proper and equal spoke tension on the low-spoke count wheelsets is as you would expect: twice as critical as a wheel with twice as many spokes. Also, at the first hint that one of these wheels is out of true, they need to be re-trued by a qualified technican whom the wheel's manufacturer will recognize as such so that your warranty is not adversely affected.
Originally Posted by FHB
All of that said, Santana has gone out of their way to suggest these wheels are problem free and, yet, folks do have problems with them from time to time. I don't think that's completely unexpected, but often times their response is. So, if your dealer did not provided you with any care & use instructions for these wheels when you purchased them, alone or as part of the tandem, then I would say the burden of proof that you failed to properly maintain the wheels in accordance with any published instructions that they did not provide to you at the time of sale is on your dealer and, in turn, Santana. I would make this request this via phone with your dealer and if necessary with Steve Lesse at Santana and follow-up in writting with a specifc request for a remedy/repair at their expense, despite being 6 months out of warranty under the premise of "good will". Even if your dealer is working with you on this, I would still call Santana and let them know that you are having a problem and working with your dealer on the remedy.
Also, since you're inclined to stick with the Sweet 16's, I would also see if your dealer / Steve Lesse would be willing to entertain a generous trade-in credit for your current wheelset on a set of the newer "stronger" wheels with the longer warranty. Alternatively, you could push for a warranty replacement of your current wheels under "good will" and push for a deep discount on a new wheelset (new business for your dealer / Santana), then put your rebuilt wheels up for sale to defray some of the cost of the new wheelset.
Just some thoughts on how you could proceed. No guarantees.
I don't have yet a year's experience with tandem wheels.
But based on my single bike wheel experience, I will opine that 3000 miles & 2.5 years is not too shabby for a set of low spoke count tandem wheels.
I might be inclined to make a stab at some sort of redress. Or, I would buy a new rim and have the wheel rebuilt and have the front wheel tensioned/trued at the same time.
From a recent Email from Bill McCready... Purportedly, the current high watermark for trouble-free mileage on a set of Shimano/Santana Sweet 16's is 12,000 miles. However, it was reported that about 1% of the wheelsets sold to date have had problems, most of which related to spoke tension. In this note he suggested that there is documentation provided to buyers that addresses the need to check the spokes for tension. However, there were not a lot of specifics.
Originally Posted by galen_52657
Tandem wheels, at least conventional ones with as few as 36h, can easily last 20,000 - 30,000 miles under average conditions IF they were built properly, are kept true, and don't fall victim to potholes or other damage. We have one set of '98 Phil Wood / Mavic CXP-30s with 12k miles that are now "spares" (set side while we beta tested some other wheels) and a very strong, ~300lb team with the identical '98 wheelset had their identical wheels rebuilt following this year's NWTR after spoke-hole fatigue began to show up on the rim with some 25,000+ miles of use on several continents and all over the US. Note: the two aforementioned wheelsets have 145mm rear spacing.
Thank you for your thoughts and insight. I have "spoken" to the "great Bill" and have decided to have Santana replace the rim and spokes. He has cut me a small deal, but it is still painful. I have asked Santana for the wheel tension specs. They have stated that the spokes should be set between 100 and 150 kgf. Despite the fact that my 1991 Wheel Smith spoke tensiometer is not calibrated that high, I should be able to take a reading when I receive the rebuilt wheel and use this for future reference. They also have confirmed spoke dope will be used in the making of this new wheel.
I have the original 40 spoke wheel set that I use on occasion, and have also built up a set of 36 spoke wheels, 14G, Sun Metal narrow rims on Phil hubs. These wheels have seen many miles and have saved both myself and another Sweet 16 user from riding the sweep wagon to the finish. The total weight difference between this Sun Metal/ Phil wheel set and the Sweet 16s is approx 230g. Not bad for a conventional wheel set. Phil was able to supply a rear hub with the 160mm spacing that worked out just right.
Do you know if the Rolf tandem rear wheel can be adapted to 160mm? Based on what I have read and measured, the Rolf wheels may be about 70 to 100 grams less per wheel, than Santana's latest Sweet 16 offering. We have 2 CoMotions in the club with this wheel set with almost twice the miles that I have with no issues. The crews on these bikes are lighter and their standing styles are not as aggressive, so this may have something to do with the better longevity.
You'd need to check with Co-Motion or the folks at Rolf to ascertain if they have already produced or sourced extra-wide end caps for the axle to permit installation in a 160mm drop-out and what if any implication is for warranty coverage. Assuming they don't have any provisions for adapting to 160mm drop-outs, Phil Wood has a wide assortment of end caps that could probably been machined down to work and of course you can always have a machinist make them from raw stock.
As for feasibility.... unless you're racing and need the aerodynamic advantage to improve your placing or just really like the bling factor of the low-spoke count wheels, the additional cost and added headaches associated with them when things do go wrong, it's hard to rationalize their use on a daily basis. However, since they do look good and seem to offer some performance advantages that folks are pleased with they will become more pervasive just as they have on most solo bikes. And, in this regard, if I had a 160mm rear spaced tandem and wanted a low spoke count wheel I'd stick with Shimano / Santana wheelset... the hubs are certainly as good as the ones used by Rolf and the rims and spokes are proprietary to both so there is no advantage to one brand or the other. Durability and longevity are TBD for both and they are equally succeptible to spoke tension problems. So, assuming you keep the spokes properly tensioned on either wheel, spoke pull-throughs and spoke hole fatique should happen no more often on one than the other and, unless you're using disc brakes, the rims will all need to be replaced at some point in the future due to braking surface wear...
So, perhaps the lessoned learned is, implement a regular wheel maintenance program on your Sweet 16's that includes checking the rims for trueness before each ride: remember, an out of true condition, no matter how slight, is a clear indication that the spokes have gone out of tension. A tensionometer will be needed and you must guard against overtightening the spokes on a low spoke count to preclude a spoke pull-through. You'll also want to have the internals cleaned and lubed on at least an annual basis. Actually, these are just the basics for all wheels, but they become more important when fewer spokes are being used to carry the load vs. a 36h wheel.
Rear wheels, of course, get a lot of torque, compared to front wheels.
Having said that, we have run 36H rear wheels for over 30 years. Rim failures/broken spokes: Mavic rims lasted between 15 to 25,000 miles on the rear.
One Mavic rim, on the front, rolled 56,000 miles and then we sold the tandem!
Very few spoke failures. Years ago we did pop a couple spokes in our rear wheel on our Assenmacher when we were torqueing hard up a set of long hills . . . ping! ping!
Also, in northern Arizona we popped a spoke in rear wheel while descending/braking down the very winding/steep Oak Creek Canyon going into the Red Rock country of Sedona.
A well built wheel (and I do not build wheels) is worth the extra $$ a good wheelbuilder charges.
Currently have over 8,000 miles on Velocity Aerohead rims 32H front and 36H rear, mated to Chris king hubs and using DT Revolution DB spokes. So far so good!
Marketing/hype will boost sales on some products . . . so buyer beware!
Pedal on TWOgether!
Rudy and Kay/zonatandem