The Golden Wrench

A blog about bicycle repair and maintenance by the mechanics at Freewheel Bike.

Thursday, October 27, 2011

This In An Old Shockspital Post Someone Asked About

  I repair a lot of Fox Alps Rear shocks. The downside of these shocks is that they have two major failure modes.

  1. The strut cracks and the shock will not hold air anymore. Sometimes I can replace the strut with a used one. Used ones are getting harder and harder to find so the this is becoming harder to to.
  2. The Eyelets crack. Same story here.

  If you have an older Cannondale this can be a real bummer because nothing else fits in place of the clevis mount Fox.

 SNC00227 But the guys out at Risse Racing put together some of their Genesis Air Shocks for me and they have the clevis mount!! Yeah! The retail is $198 and they out perform the original Fox Alps.

   So if your shock can’t be repaired this is a really nice to keep your bike going!

The Moonlander Had A Moonlanding At Midtown

Karl was busy taking measurements and recording all the pertinent information.
The new Surly Moonlander seems to be much lighter than its Pugsley predecessor. And boasts a much larger tire.
You should come up with questions to try and stump Karls initial information gathering efforts. I am sure his wheels are already turning planning some crazy future Moonlander project.

Tuesday, October 25, 2011

Rohloff Internally Geared Hub Service

Today I'll be showing everyone how to change the oil on a Rohloff Speedhub. I've been riding mine since June and have put about 500 miles on it so far. Rohloff recommends an oil change annually or every 3000 miles. Since this hub may see winter duty it's a great time for the initial oil change.
No matter which configuration of the Speedhub your bike has, you can leave the wheel installed. If you're using disc brakes now would be the time to remove your rear brake pads. With a little care the pads may be left installed and a clean rag placed over the caliper to catch stray drops of oil. Tools/Supplies
  • Rohloff oil change kit
  • 3mm hex key
  • 8mm box wrench (optional--for EX box when unmounted)
  • spray cleaner
  • rags or cotton swabs
Clean the rim and hub shell, especially around the drain screw, to prevent debris from entering the hub. The Speedhub should always have 25ml of oil inside to run as smoothly as possible. I will be adding oil and then removing the used oil and replacing it. Rohloff has a cleaning oil and "all-season" oil produced specifically for the Speedhub--nothing else should be used. The cleaning oil, at a lower viscosity, acts as a solvent to thin the all-season oil and remove any contaminants from within the hub. Draw 25ml of cleaning oil into the syringe fitted with the tube and drain plug. Rotate the wheel so that the drain screw faces upwards. With a 3mm allen key remove the drain screw from the hub and carefully thread the syringe into the hub. Slowly inject all oil into the hub, remove syringe and replace the drain screw.
To fully rinse the old oil from the hub you can spin the cranks or go run a short errand with the cleaning oil inside the hub. If you're doing all this in the shop you can spin the cranks for a few minutes at a decent cadence and switch between gears 3-5. Have a snack or relax for a few minutes to let the used oil settle inside the hub. Again, rotate the wheel so the drain screw is facing upwards, remove the screw and install the empty syringe. Rotate the wheel so the syringe faces downwards and slowly draw as much oil as possible from the hub. You won't be able to remove all 50ml from the hub because some will always stick to the gears. I managed to draw out ~35ml and you should expect about that much. Rotate the wheel so the syringe faces upwards, remove it and dispose of the spent oil. Usually, you'd fill the hub with 25ml of all-season oil, but for cold weather you can mix the oils without worry. I'll be using the maximum 1/1 ratio of cleaning to all-season oil. Draw 25ml oil into the syringe and mount to the hub. Fill the hub, but take care to equalize the pressure within the hub. You may notice more resistance on the syringe with the last bit of oil. The plunger may spring back--take your time with the oil and allow the plunger to naturally return to "zero". Once the syringe is empty you may draw a little air from the hub to prevent pressurization. Replace the drain screw. Don't forget to replace your brake pads.
All done!

Monday, October 24, 2011

Brass Mass

This is where the magic inside an older terra
logic is stored.

Thursday, October 20, 2011

You Wanna See The Inards?


I got some feedback!!

1. I always thought the idea with copper paste is to put it on the back of the disc pad where it contacts the piston. That's supposed to stop the high-frequency vibration between pad and piston, which can cause squeal.
However, I've never found this to be a problem with modern disc brakes.
If you can get it in the USA, I find Muc-Off disc brake cleaner to work really well.

2.I deliberately avoided being sarcastic in my last comment, which has been deleted! I would have thought that someone with 'the touch' when it comes to disc brakes, would know that putting copper paste onto the pads and disc (and not the backs of the pads, where its supposed to go) will ruin them.
This article makes you look a bit foolish.

Don, no comment was deleted; it just takes a bit for moderation to catch up. And for the record I do not have the ability to moderate comments that is handled by someone else. AND I have never deleted a comment on any blog that I sit on and there are quite a few.

Your comments are spot on. Everyone makes mistakes and maybe I have made one; maybe not. As I have said I am waiting for Motorex to get back to me because they were not clear as what should be done with the copper paste. And in all fairness it was offered up as a competitor for the Squeeeall Out, so I just went ahead and treated it as if it was the same style of product. The instructions aren't super clear but the context seemed to be.

So... when I get a chance I am going to try Don's idea, it certainly seems more feasible and I will get back to you.

B "$.02" Rose

Monday, October 17, 2011

Battle of the Disc Brake Cleaners

People ask me about cleaning their disc brakes all the time. "Should I use disc brake cleaner, gasoline, boiling water or alcohol?", is something I get at least once a day.
People don't always realize that I consider my real specialty to be disc brakes. I have always had the touch when it comes to disc brakes. I have more bikes with disc brakes than suspension also.
So when two products showed up at on my desk both claiming to eliminate squeal I was very skeptical. I have done some preliminary testing and there are three things that jump out at me so far;
  1. Squeal Out: This is a gritty goup that you put on your pads and rotor. Then you actuate the brake lightly for a little while (don't ride any real distance with this stuff on your brake) and then clean it off. It actually works better than I thought. One thing it did really well was quiet down the feedback you get from mechanical disc brakes. If you are running mechanical brakes and you get weird tnk, tnk, tnk, tnk noises as you apply the brakes this stuff seems to hone everything done and give a quieter smoother feel.
  2. Motorex copper paste: This stuff seemed to hone the pads and rotor also but we could NOT get it off the brake. So the brakes got quieter but we were not able to clean the copper paste off afterwards so the brakes didn't develop power after we used it (but they did not squeal). I have sent an email to ask Motorex if we used it right because the jar is thin on instructions.
  3. Dawn dish detergent and water: Still the best! I learned to rely on this back in the Cannondale days when working on CODA Competition brakes was a daily occurrence for me. Its easy on the environment, easy to clean up and cheap! Keep an eye on the Shockspital Blog for some handy tips to manage your disc brakes in the future; including the secret of letting Dawn make your life better.
And as always I learned that boiling your pads doesn't help, Speed Clean and other "disc brake cleaners" are OK for your car but generally aren't the best idea for your bike (most are petroleum based).

I will follow up on this again as soon as I hear back from Motorex. Motorex makes a great selection of shock oils and the very BEST, MOST recommended DOT fluid on the market as far as I am concerned. So I am interested to hear more about their idea of what the copper paste will do for disc brakes.
--B Rose

Saturday, October 15, 2011

In Praise of Prevention (yes, Prevention)

Here is some stuff you've heard a million times, with a few timely cliches mixed in for variety.
  • Honesty is the best policy.
  • The bubbles in bread are yeast burps.
  • Maintaining your stuff will make it last longer.
  • Bike stuff is getting more expensiver all the time. Cyclocross tires (!!!) are more than ATB tires, for heaven's sake.
  • Maintaining your stuff will make it last longer.
  • Motorex suspension fluids are very nice.
  • The length of time for which the stuff of you lasts is in direct proportion to the amount of maintenance you throw at it.
So mix all those truisms together, set it aside and cover it with a cheese cloth while you make the gravy.

Wait, no! The point is that your fork is an expensive, complicated thing. Retail on a middle-of-the-road fork (as in, 4 pounds, 26" wheel) is still going to be $400 to $500. For a nice fork, think $800-$1000. Inside, there are springs, dampers, liquids, protons, valves, nitrogen, mouse droppings, radio waves, shims, gases, and (if it's a Magura) the faintest hint of schnitzel.

Just like anything else, there are parts in this system that break down over time. For example, the top seals usually last about a season before they start to either weep oil or allow dirt inside the fork. The foam ring that keeps oil on your upper tubes gets corrupted faster than that. Damper oil has a shelf life, and can migrate past o-rings to places it doesn't belong. Speaking of o-rings, they are wear parts as well, and can begin to leak air and fluid.

What will you notice while these things are happening? Probably not much. Remember, you're the one who has been wearing the parts out, so it's likely you won't notice that much has changed because most of these parts don't puke in the middle of a ride. They wear out slowly, and eventually your fork stops doing anything productive besides weighing the front of your bike down. At least you won't notice until you get on a bike with a new or recently-serviced fork. There you will notice that the compression stroke is smoother, you get full travel, the rebound feels better, and all the adjustments turn easily.

Forks are sensitive to neglect, and performance can deteriorate without you even knowing it's happening. If you're racing, you need your fork to be working properly, or else you'd be riding rigid and saving the weight. If you're just riding, you want your stuff to work right. Don't wait for black goop to come out of your top seals. Don't wait for all of the oil to leak out on your garage floor. Don't wait until your compression stroke feels like your unshaved legs in late September and you can't hold a good line in corners anymore.

Changing the oil in your car is always cheaper than changing the engine in your car. Changing your the filter in your furnace is always cheaper than changing your furnace. Changing the diapers on your children is always cheaper than... uh... something.

Preventative fork overhauls are always cheaper than "my fork is leaking and clunking" overhauls.

Thursday, October 13, 2011

Shockspital Is Truly Home

This might seem like just a box to you; but to me it is much more. I have worked very hard for a long time to make Shockspital special but it really took Freewheel to get it to the next step. It looks like a box but its really a milestone.

Wednesday, October 12, 2011

Knowing When To Stop...

This was a step to far...

Manitou's Absolute Plus Tuning System

Recently the mechanics at Freewheel Bike, the new home of Shockspital, were introduced to Manitou's new Absolute Plus Tuning system by Shanan and Ed from the Hayes group.
I'm excited about this system because it is the first time that bike shops are able to easily perform true custom tuning on suspension forks.

This is Shanan in the white shirt. He's been with Manitou for a loooong time. If you've ever called Manitou for tech support chances are you talked to him.

This is Ed. He's and engineer (note the white board).

Ed was explaining the difference in damper shim thickness. It all seemed to make sense at the time.

This is the tuning book that comes with the kit. It helps you choose which shims to use to tune the fork for individual riders.

This is the parts kit. It comes with damper pistons and shims.

Wednesday, October 5, 2011

Di2 on a Cronus CX???

Frankenbikes, Jackalopes, and Velos-Kludges are some of our favorite things. The average mechanic's bike is usually a mixture of old, new, beautiful, ugly, and well-loved items that have been accumulated and curated over his or her career. Coveted items such as Mafac brakes, Dura-Ace 7400 anything, beleaguered Flite saddles, and old Hugi hubs find their way from bike to box, and box to bike until either Sir Isaac Newton enforces his Second Law, or an unexpected rent payment comes due and it's time to liquidate some capital.

Here at the shop, we tend to accumulate old parts from repairs. Usually the customer is either traumatized by what happened, i.e. "the velociraptor what ate my leg also done messed up my shifter, and therefore, I don't want it around, lest I get bad dreams" OR, he or she doesn't want to pay to have the parts fixed. In the case at hand, it was the latter.

One of our favorite customers busted up a brand new Trek that was set up with Dura-Ace Di2 shifting mess of goodies. Out of the wreckage (WRECKAGE, let me tell you now!), we were able to salvage most everything from the Di2 setup except the front derailleur, whose cage was pretty much destroyed.

The frame could fit in a laundry basket. It was a mess!

OK, so we successfully dissected it. What do we do with it? Not much call for a 1x10 road bike these days, and getting all the little aftermarket doodads from shady websites to make it into an allegedly mountain-compatible setup would have been expensive and risky.

Well, Kevin the Boss Man rides his bike furiously and occasionally falls off and breaks himself. He's sort of a "tape-it-and-play" type, so things like sprained wrists and broken thumbs don't really slow him down that much. Truth be told, he has watched too many Civil War documentaries and is afraid that his doctor is going to furrow his brow with his arms akimbo, sigh gravely, and reach for a hacksaw.

His crunched-up hands and wrists tend to limit his range of motion for the big throws required to shift some road groups. So when he got a deadly new Trek Cronus CX rocketship for gravel roadin' and CX racin' and single trackin' and stuff, shifting the bike in the heat of battle was a literal pain. Since we had the busted-up Di2 set sitting around, we decided to try to retrofit it.

"But I don't want to be a Di2 bike, guys!" said the Cronus CX in that whiny "I own you and you will buy me a pony" sort of voice.

"You're gonna be a Di2 bike and you're gonna like it, you lecherous, sponge-bathing, Froot-Loop devouring circus midget reject! That's the problem with kids like you and your roller skates and your dungarees, you don't appreciate quality. It's all ball bearings and transistors these days"

"But I look all stupid with a front derailleur that isn't a front derailleur! I'm a 1x10! Nobody in the entire Rutherford B. Hayes Memorial Jr. High is going to sit by me in the cafeteria! I'll be such a loser in the game of life, and I've only just got started at it!" said the Cronus CX, with an appreciable flow of alligator tears.

"Fine! We'll stuff the front derailleur remnants inside the down tube, will that stop your sniveling? Don't push your luck, or I'll turn this car right around! So help me, I'll fill your shorts with pork chops and make you walk home in this bear-infested wilderness!"

"Oh, look at me! I'm as lithe and supple as a figure skater now!" said the Cronus CX, all 1x10 and electric-shifty.

Will it hold up to the Boss Man's crashing and bashing riding style? Time will tell. All the wires and stuff are tucked up inside the downtube, but the battery is still exposed to the elements. And it will see elements.