Tuesday, March 12, 2013

Ultegra 6700 Hub: Near Death Experience

Last fall my back wheel, the expensive, custom built one, developed an annoying creak. It's an Open Pro Mavic Rim attached to an Ultegra 6700 rear hub via 14/15 butted DT spokes on the drive side, and 14/17 super-butted spokes on the NDS.

After spending hours trying to relieve the spokes, and generally driving myself nuts trying to remedy the creak, I gave up and put my nearly identical spare on, and have ridden that the last 8 months. A couple of months ago though, I realized it was time to get ready to replace my "winter" wheel with my summer wheel, and decided to repack the bearings on both in the process of swapping them out.
Parts replace were 5,6,8,9, and 10,11,12,13. Photos are of #10's cup surface
I was shocked to find both cups and cones on the drive side pitted and spalled on my spare wheel, (purchased from PBS at a huge discount). I realized that since it was my spare, and having few miles on it, I had NOT repacked it in 2 years, as it still had factory grease in it. This was either an appalling factory lubrication failure, and/or, a serious QA problem for Shimano. I really have no idea where the blame lies, but you will note there is micro-pitting and a bit of rust all over the cups.

Pitting and spalling of an Ultegra 6700 rear hub
It's important to understand that normally for loose ball bearings, a pitted cup has no remedy, and the hub is ruined - garbage to be hurled into the trash can in disgust. For Shimano hubs (and many others), there is one exception though, and that's the drive-side cup in back, as the cup is actually part of the free-hub body, and is NOT pressed into the hub as all the other cups are, both with front and rear hubs. (the other side of the cup is a cone for the internal free-hub bearing - pretty clever)

I took the good free-hub body off my creaky, custom wheel, the axle with 2 good cones, and was able to put together one good wheel by cannibalizing two bad ones. There's definite advantages in having two identical, or in my case, nearly identical wheels (the PBS wheel uses 14/15 double butted Wheelsmith spokes on both sides). Since rear wheels are much more likely to break than front ones, having two identical rear wheels is much more important. Think about relative tire wear in the front and back, and double or triple that. 

 I ordered a new free-hub body from Amazon, and a new cone from Performance Bike Shop, who happen to remember they're a LBS, and should provide this service. They did so after a complete failure the first time (they lost all record and recollection of the order, until I jogged their memory, and then they just shrugged), 6 weeks of waiting, and then a week waiting for the re-order. When I went to pick the drive-side cone up, they informed me they couldn't sell just one - in clear contradiction to the two cones, each with their own part number, plastic bag, and price. I HATE being lied to!!!

$20, plus tax for the two cones, and $45 for the free-hub body. I'd RX getting the 2 cones along with the axle in a rebuild kit for $30 - a better deal IMHO. $65 is a lot of money to put into rebuilding a hub that didn't cost much more than that when I bought it, but the alternative was to toss the entire wheel. Nasty thing, having a nice wheel wrapped around a bad hub. In fairness to PBS, the 2nd mechanic I dealt with was very professional.

I'll see you on the dark side of the moon. Very hard to photograph. These are the best of 100+ attempts.
When the parts came I mounted them on the custom wheel, resigned to having an expensive creaky wheel for all my trouble, but still a spare. I'm not sure if it was the new free-hub, the RnR process, the new cones, new balls, or Teflon grease, but the creak is GONE!

 I now have 2 good wheels, assuming I don't find anymore nasty surprises when I repack my winter wheel, and I have replaced the stock bearings, which have G20 balls, with G10 balls I bought in bulk from Amazon.com. Btw, balls are rated according to their tolerances, so the smaller the number, the tighter the tolerances, and therefore, the better the balls. G10 is as good as steel bearings get. You can get G5 ceramic balls, and that is an advantage in having loose ball hubs. Generally though, my enthusiasm for loose balls has dissipated significantly. ;)

This looks like a spectacular grease failure. I think this was factory grease. I packed the new bearing with pure Teflon grease spread on the cups and cones, and then packed full with Finish Line grease with "some" Teflon in it. I assumed since it contained Teflon, it would be compatible with pure Teflon grease. It's usually a bad idea to mix greases.
 This brings me to an important point. If you have cartridge/sealed bearings, (a misnomer, as all bearings have seals) you don't have to worry about the cups getting pitted or spalled. You replace the cups, cones, balls, and seals whenever you replace the cartridge bearing. The downside is, you're paying a lot of extra money for parts that aren't usually needed, so for any given price point, you get better quality bearings in a loose ball hub, AND, you can get them. Chris King, for example uses his own in-house mfg-ed sealed bearings - which he doesn't sell to the public.

Close to what I've been using, which I purchased at $120 an oz from an aerospace contractor, so it's MIL-Spec. This should work just as well for 1/6th the cost. Spread in zig-zag pattern across the ball path on the cups and cones before packing with the grease below to hold the balls in place while placing them in the cup. The very best grease for preventing spalling is 100% Teflon grease. Hard to find.
Good, basic bearing grease for bikes. Basically, I use it as a filler to displace water and dirt, and let the pure Teflon do the work of keeping the bearings rolling.

There's nothing very hard about replacing or repacking ball bearings, nor free-hub bodies. It pays to swap your wheels out at least once a year, and at least repack them. The G10 balls are going for a dime a piece at Amazon. There are 18 in back and 22 in front. Well worth the trivial expense in my view.
Morningstar Ball Tweezers
Highly recommended is a constant tension ball tweezers. They hold the ball with a constant force, which you relieve when you want to release the ball. This guarantees you don't scratch the ball by squeezing it too hard. It also makes holding the slippery little devils much, much easier, and allows you to press the balls into a cup's grease pack, which will hold the balls in place until you can place the axle and cone to keep them from falling out. 

This one has a brass ball holder, which makes scratching a ball impossible. These are tools mechanics treasure. A source of bragging rights for those who know how easily balls can get scratched. When working with bearings, every attempt should be made to maintain a surgically clean environment. A human hair mixed in the grease, speck of dirt, metal fleck, or bit of rubber seal will degrade and/or ruin a bearing. It is absolutely essential that your tools, hands, rags, and general work area be absolutely CLEAN!

I am happy to report that the creak is gone, so almost worth the $65 bucks. Now I can focus on building up a new speed wheel in back, based on my old Alex wheel hub, DT Swiss bladed spokes, and a DT Swiss R585 30mm deep rim. With 24 spokes, and the 30mm profile, it should be slippery, and since the Alex hub is pretty light, a reasonable weight as well.

Monday, November 19, 2012

Lighting 2012: Helmet Mount for Headlight Pt II

Like historians, who didn't know to number "The Great War" until the next one came along, labeling it WW-II, I find myself needing to update my helmet lighting again after just a short time.

I was ordering bar tape to match my new saddle and needed to order a few extra bucks worth of something to get free shipping, so decided to splurge and spend $37 at Amazon for a Fenix E25 2xAA cell flashlight.

I almost sent it back when it arrived, because it looked too big. Too big for the mounting system, and too big for the top of a helmet. In the end though, a frontal area only 26% that of a MagicShine was appealing, so I cut it out of the package and tried it in the mount.

Whoot! It fit. Just barely, but it fit. Tight enough I aligned one of the groves in the hand hold area with one shoulder of the clamp on the bottom, but it fits quite nicely. Even with the extra thickness of a star and cut-washer set of lock washers, the bolt was long enough I could get it started by squeezing the clamp shut lightly while starting it in the threads with a screwdriver.

Two layers of Velcro straps go on either side of the Volt's "V". Note topside position of the 3-position switch, sealed by the grey rectangular patch on top

Note how the back half of the shoulders on the shoe are cut away to improve the fit

The retention tab, covered by 2 layers of Velco straps, in addition to the Velcro stuck to the shoe and helmet, provides excellent front-to-back stability.

Light is mounted slightly behind the center of gravity to allow angling it up enough to point it well up the road when in the aerobars

Minimal frontal area and low-profile mount makes this aerodynamic, silent, and keeps the weight from shifting the helmet around.

The E25 is a little long. An E35, powered by a single 18650 LION cell would be better, but the price is close to that of a Cygolite then, and this mount doesn't allow you to slip the light off when riding in daylight. It does allow you to walk into "Bertha and Bubba's Bait Barn" anywhere in the US and buy AA alkaline cells on double centuries.

The involvement on the inside of the helmet is minimal, and being a soft mount, doesn't compromise the structural integrity of the helmet's protection in any way I can detect.

This shoe got covered with an inch of soft-side Velcro which added a lot of stability when interfacing with the scratchy side Velco stuck to the helmet

The "Velcro" comes in rolls, and isn't Velcro, but a Chinese rip-off with smaller loops and hooks. It is just a bit stretchy, which really helps when doing a soft mount like this. The Fenix LD01 is pictured here for scale.

I had already futzed around with the Velcro on the mounting system before trying this, but note that the new approach is cleaner and more stable. The changes to the system are as follows.
  1. I cut the shoulders off of the shoe about half way from back to front to get a better straddle over the helmet's raised "V"
  2. I ground the shoe's retention pip off on some concrete (crude, but effective) to make the shoe completely flat
  3. I covered the flat part of the shoe with a strip of self-adhesive soft-side Velcro to interface with the scratchy-side Velcro already stuck to the helmet top
  4. I ditched the red Velcro strap running side-to-side as the mount is completely stable side-to-side now without it
  5. I added a 2nd layer of front-to-back mini-Velcro, running one layer on the right side of the Volt helmet's leading "V",  and one layer on the left side
  6. I added a star lock washer against the plastic of the mount, and a cut-washer type lock washer against the bolt head. This keeps the screw from unscrewing itself when you work the tilt mechanism back and forth when transitioning from the blocks to aerobars and back.
In the end, what made the decision to keep the E25 easy was it's extremely tight beam pattern -  1.5ft @ 25ft, and able to paint reflective signs at over 5 blocks. It lit up the dozens of trash cans in the bike lane on California Ave for 2 blocks ahead, and almost blinded me when I accidentally bounced the beam off of a 4x4' yellow speed caution sign.

I also appreciated that it was very easy to point away from oncoming riders on the ARPT by pointing it at the shoulder 20ft ahead, knowing that almost no light was spilling out into the oncoming rider's eyes. I had no difficulty at all seeing where I was going, even looking into lighting in the 2,000 lumen range from multiple bikes riding in a paceline. It's that bright! (rated at 156 meters, and it's all of that)

In talking to endurance riders, those that ride double centuries, Brevets, and 500+ mile rides, as well as devoted night riders and commuters, one thing comes up again and again. The battery life of headlights should be at least 2X your greatest need on the highest setting. The alternative is constantly 2nd guessing yourself about how much light you can afford to use, fearing complete darkness. The more challenging the ride, the less welcome this constant nagging thought becomes.

I'm going to try a single 18650 cell flashlight just for grins, as it will be smaller and should last longer, having 1 X 3.7v X 3,000mAh or 11.1 watt-hours of energy stored, v.s. 2 X 1.25v X 2,700mAh or 6.75 watt-hours of energy, and will be lighter as well.

In the end, everything is going to be powered by 18650 LION cells, because this is what electric cars, like the new Ford C-Max Energi are using. CygoLite uses these in removable packages in many of their lights, but as yet, you can't walk into a gas station in a remote area and buy them like AA cells. 

If you give up on a battery solution for the duration of the ride, then by all means go with batteries that are readily available along the way. The 1st time you are humping a bunch of dead batteries up the side of a mountain 10-12 hours into a double century, this will become abundantly clear.


Sunday, October 28, 2012

Lighting 2012: Helmet Mount for Headlight Pt I

What started out as a map light to light the Garmin 305 Edge, thermometer, and the tops of the bars morphed into a headlight as well with the incredibly bright Fenix LD01 "pen light", which puts out 85 lumens on high.

The one frustration I've had with this light, is getting it to tilt up for lighting the road properly, especially when riding down in the aerobars, and down again when I want to read my Garmin or thermometer.

With an upcoming 25 hr noon-to-noon ride on the 4th, when we "fall back" to end DST for 2010, I wanted this problem solved. I started looking at the mounting options I had laying around, and in an epiphany, I realized that the body of the Fenix is the same size as the seatstays on most bikes, so by swapping the roles of the clamp and the mounting shoe, I could make a perfect flashlight holder, purpose made to tilt.

The first mount I made was for my Bell Volt Helmet, and then, just to test the flexibility of the Velcro approach, I did another mount on an old Bell Ghisalo helmet, where the shoe fits down into the vent hole on top of the helmet, so is VERY streamlined.

Despite the scale these close-ups seems to imply, these lights are not much bigger than the AAA cells that power them - very GOOD AAA cells would be my suggestion. I'm using mostly Sanyo 1000mAh cells, and carry 2 extra batteries in my saddlebag, in addition to the 6 that power the taillights.

The red Velcro I got from an auto parts place, and the black from Amazon. The black version is not Velcro, but some "hook and loop" system, which scaled down in every way, and doesn't interface well with the normal sized Velcro. Both work well, and it's nice to have the flexibility of 2 sizes, but they won't stick to each other properly.

I've also replaced the Blackburn Mars 3.0 with a 4.0. It's easily 3-4X as bright, about half the size, weighs slightly less, has the same mounting system, but is sans the rarely used "marquee" flash mode. It still, stupidly, uses colored lenses when LEDs already produce the proper color all on their own, so the colored lens just blocks light needlessly. Planet Bike has wisely used clear lenses, and a translucent white body so the whole case turns red in constant-on mode.

On the plus side, the Mars lights have a simple flash pattern that can be tracked, not as well as in constant-on mode, but still trackable in a pinch. Their hose clamp mount makes for easy helmet mounting, and they have amber lights on each side to properly indicate to traffic they're looking at you from the side. (reflective tire sidewalls and wheel reflectors do this too)

Before, with Blackburn Mars 3.0 taillight and Velcro mount

After, with Blackburn Mars 4.0 and Velcro-ed PB seat-stay mounting system with dyslexia.

Velcro running in both directions for a good anchor. Note the lock tab forward where the back Velcro passes over it before being threaded into the inside of the helmet.

View of the inside of the Bell Volt helmet. Always run Velcro UNDER the helmet's sweatbands.

2 layers of Velcro under the shoe. One sticking to the helmet, and one on top of that (red) running under the PB mounting shoe

Close-up of mount. Easier to do the Velcro work with the clamp OFF, especially when running the black Velcro across the top of the red.

Note the receiving slot of the PB mounting shoe clearly visible here. I may cut the vertical part of the shoe off later and put some adhesive Velcro on the then flat shoe to make this an even more stable mount.

Fenix LD01 flashlight is mounted right at the balance point so it will have no tenancy to tilt up or down

The lock tab on the PB mounting shoe is clearly visible on the front side here

Bell Ghisallo helmet with PB receiving shoe mounted down inside the top vent hole

Black Velcro holds the shoe forward, tightly against the tapered front of the vent hole

Note rubber spacer wrapping the flashlight. Its cushion is required to allow the teeth in the tilting mechanism to slip past each other. Also note that the slotted holes in the wide part of the red Velcro were both worked down around the leg on the shoe that holds the clamp to it. With Velcro running in opposite directions, this makes for a great side-to-side mounting system.

These Velcro straps have just the right amount of stretch for this application, although the mount benefits from a rather tight cinching. It's also worth noting that using this same approach, a pretty large flashlight, or headlight, could be mounted if the small clamp were replaced with the large clamp.


Friday, July 20, 2012

FAIL Whale: Performance Bike Shop

I have been waiting to post the R&R of my broken Shimano 6703 shifters for Performance Bike Shop to complete the exchange - which they have FAILED to do.

Out of frustration, after 7 weeks, I took the duplicate set of shifters they sent me to the local store and asked them to credit my card. Because the item was over $100 they FAILED to do so. This after waiting 8 days for a snail-mail that was supposed to contain a Fed-X label for the return - the 2nd such label has FAILED to materialize.

After 9 days, I called the local store, and they have FAILED to receive any indication my package was returned to PBS's return center, or resulted in a refund.

It is very apparent to me that Performance Bike shop is on the ropes financially. There are a few indications of this. 1st, and foremost, any healthy company would have a functional CRM software system in place by now. PBS's system seems to be ancient, and badly broken. After a half-dozen extended phone calls, and a store visit, NOTHING is in any system anyone at customer service can find back. This is beyond pathetic.

By contrast, Amazon.com had good CRM in place by the 2nd yr of their existence, and currently handles all returns completely online, printing both the return authorization and mailing label on your printer so you can ship the package back, with complete confidence it's being tracked, and everyone knows the complete history of both ends of the transaction at all times.

The other indication PBS is on the ropes, is they've dropped a lot of vendors, and my guess is, the remaining ones are having to finance PBS's inventory.

Finally, their prices are no longer the best. Amazon can usually meet or best their price, and offers free shipping and no taxes to boot. The tax treatment is something PBS can do nothing about, but even ignoring that, PBS no longer is price competitive. My guess is, Amazon has pushed them to the brink, and they are going down.

The local PBS guy asked me to wait another week. After that I'm going to call my card company and take my money back. I'm beyond disgusted with these nit-wits.

UPDATE: 7/ 26/2012

I got a call from the shipping manager (the person who I hand-delivered the redundantly shifters to on 7/11) at the local Fair Oaks Performance Bike shop on Monday the 23rd, in response to inquire on Thurs the 19th.  Nothing.

I called today, Thur the 25th, 2 weeks and a day after returning the shifters, and talked to the sales manager. Nothing. Promised they would escalate the matter with the store manager tomorrow and call me back after I threatened to have my credit card company revoke the charge, and/or call the local TV stations. Beyond pissed off!!!

UPDATE: 7/27/2012

Got a call from the shipping manager at noon today. The return package was received on the 24th, but only after burning up a lot of phone line were the local shop people able to find this out. I wasn't entirely satisfied until I found my credit card had been credited. So 7 weeks after this debacle started I've saved $339, minus the shipping that PBS failed to reimburse me for. Draw your own conclusions. I think I'll pay a little more and get a real guarantee in the future.