Sunday, April 27, 2014

A Freewheel Tool Is Finally Replaced

People are constantly surprised when they look around our workshop at all of the bicycle specific tools that they see. They are even more amazed when we tell them that rarely a month goes by without us buying more. Every time some manufacturer designs something new invariably there is the need for a new tool to service it. Also things wear out over time and just need replacing, I recently needed a new DT Swiss hub lockring nut removal tool to replaced a worn out one, the sucker cost me 40 bucks too! Sometimes however a tool needs replacing for a different reason. About 8 years ago I lent someone my Maillard freewheel removal tool. This is a splined widget that fits the matching splines on the inside of an old French freewheel that was quite popular in the 70s. Well long story short that tool never came home, now apart from pissing me off slightly, I did not make a big deal out of it and figured I would replace it down the line. Not so easy, every time I tried to source that thing nobody had one, they are rarer than hens teeth. Now, as I said it is not a common freewhel but about 5 or 6 times a year one will come through the door and I would wish a fresh curse on the swine that relieved me of the tool. No more though, a shiny new Var tool has been delivered. I bet now that I have it I will never see a Maillard freewheel again, Oh well it will make  a fine paper weight...
Var Freewheel Remover For Maillard Helicomatic And Super Plus Freewheels


 

Sunday, April 13, 2014

Hydraulic Brakes. Make Them Like New Again.

Hydraulic Brakes are one of those components that everyone wants to have and then, when things go wrong, they bail and become anti fluid and pro cable actuated. I will admit that there are some good cable actuated discs out there that are very good, the Avid BB7 for instance, however, nothing comes close to the feel and operation of a good hydraulic system. That is why it is a shame when people ditch them. Even some bike shops are more than happy to sell the hydro's but don't want to mess with them afterwards for service. A hydraulic brake system can be ordered as a kit, hoses attached and filled with fluid. You can always tell a system that has come this way as it will have 3 feet of extra hose in a big loop off the bar, just waiting to be snagged by a passing Moose or even a tree limb. Now sometimes this is just laziness on the part of the mechanic but often it is fear of cracking the system open. So here is a little primer on the hydraulic disc brake system...

I have already mentioned Avid above, apart from making the BB7 they also make some great hydraulic units, the older Juicy and Code plus the newer series of Elixir and Trail. All of these models are easy to service and durable apart from working very well. Shimano also make a range that are popular and again easy'ish to service and repair. Other companies that we are fans of are Formula and Hope, both of these produce disc systems that also qualify as works of art, sadly they also  have price tags similar to a minor work from Rembrandt...

So, back to my point. What do you do when things start to go sideways? Well you service them.  Below I have taken some pictures of the complete internals of a set of Avid Juicy levers and calipers. These brakes recently came to us from a customer at the Lake of the Ozarks and they were in dire need of some TLC. These brakes are very common but basically all hydraulic brake units are following the same principles, so with a spec sheet of your particular make and model you will be in good shape.

These particular units had developed one of the common issues of older neglected sets. They had developed the sticky lever syndrome. Another common issue is a soft lever which means air is in the system either through the need of a good bleed or the hose has developed a hole or an o ring has failed on a bleed port. The sticky lever however means that the internal plunger in the lever is in need of replacing or that the caliper pistons are beginning to stick and corrode. My rule is; do both, if one end is gummed up and failing the other ain't far behind.

Wear gloves as DOT fluid is not something you want to be bathing in all afternoon and a pair of safety glasses, you would be amazed at how often I have shot myself in the face with a full syringe of this stuff.

I usually start with the lever first and, with a new bag of the correct internals, start cracking it apart. Below is what you end up with, again this is a Juicy so you will have a different looking pile of bits but they will be doing the same job.
Once the lever blade is removed it will reveal the circlip that needs to be removed to slide out the reach adjust mechanism and the plunger.

Reach adjust mech is next. If yours is a more basic model this will be missing.
In this case the parts were worn
All the parts laid out ready to clean. In this instance everything is being replaced except the body the blade and the reservoir cap.
The main culprit of the sluggish lever return is the plunger unit, in the above picture it is the thing with the spring attached to it. However when you are pulling it apart you may as well replace all the bits as they are all in the rebuild kit anyway.

Once the lever is rebuilt I attack the caliper. Again disconnect the hose first. The only way to get into the pistons is to split the caliper body in half. this is achieved by undoing the three bolts. Once you have the body in two the fun begins. The way to get the pistons out of their press fit home is with the use of compressed air. You cannot get them out any other way so don't be jamming screwdrivers in there or you will damage the body itself and you will get fluid leaking out and the whole unit will become a paperweight. The compressed air does a great job of popping them out. Warning; Make sure you don't have the thing aimed at anything soft and fleshy, it will hurt...
Waiting to be cracked open like a walnut...
The main culprits in here are the quad rings (the square edged rubber washers) and the round pistons.All of which will be replaced.
Once the caliper has been rebuilt all that is left is to run new hose, to the correct length as mentioned earlier to avoid lassoing stray Moose... Also never re-use banjo fittings or crush washers. Once they have been tightened up they have to be replaced. That's it, job done. Go ride.
Good as new.



Monday, April 7, 2014

Custom Made Wooden Rims.

Over the last year we have been working on a couple of unusual projects. We have mentioned before the Bamboo bike frame that was completed recently, which we will feature here before too long, as a follow on to the frame project however we have a set of wooden rimed wheels.

These things are beautiful, we have dealt before with an Italian rim manufacturer, Ghisallo, but these new rims that a good friend of ours has had custom made are head and shoulders better. Our friend Tom, who has been the driving force behind the bamboo frame build, went in search of a craftsman to make these hoops and boy did he find one. They are made of white oak and have been stained and finished in a lovely medium brown that shows the grain.
The unfinished rim
 
The rim after being stained and laced up.

We used the Velo Orange Grand Cru front hub.Just visible are the DT Swiss brass spoke washers that we use.
The finished wheel.
The wheels will end up on the bamboo bike frame, at the moment though, they are hanging up in the workshop and have become quite the conversation starter...



Sunday, April 6, 2014

Square Taper Crankset Woes.

The method of affixing crank arms to a bottom bracket spindle using a square taper system has been around for many, many years now and even though we have had lots of designs since it is a method we still see a lot especially on the comforts and hybrids and anything that comes from a box store.

Because we see a lot of these cranks on the cheaper bikes does not mean that it is a bad method, White Industries make a very high end crank set that uses a square taper fit and Phil Woods produce some of the most expensive bottom bracket cartridges ever in square taper format.

If the square taper crank to bottom bracket interface has ever had a problem it has been with installation and maintenance. The basic principle behind the method is that the crank arm gets tighter as it is drawn onto the square spindle because of the tapering. The most comon issue we see is the crank arm bolt coming loose or falling out completely and the bike is still ridden. Even though the crank arm is tightly fixed onto that spindle with the bolt gone the pedaling action will break the bond within a mile of riding. Now here is were it gets interesting. People just assume that a new bolt when they get home and a wrench to tighten it up will solve it. Wrong. When the arm gets loose and you continue to ride it the square hole in the crank arm just mushrooms out. The crank arms are made of soft aluminum and the spindle is steel. Once that crank arm hole becomes deformed it will never stay put, no matter how tight it feels when tightening it back up. The only cure is a new crank arm.
This is a typical example of a crank that became loose and was still ridden.
This is what they are supposed to look like
The above are pretty generic examples of the square taper cranks that you see on multiple bikes nowadays. Below is a picture of a White Industries VBC crankset and bottom bracket. This one was recently installed on a Ti Moots road frame and made a significant upgrade to the bike.
White Industries VBC crank set in anodized black.
The bottom bracket to match.
One slight issue that you have when using the white industries bottom brackets is the choice of spindle lengths or the lack of choices. In the event that a different length is needed then the Phil Woods bottom brackets are a great alternative.




Wednesday, April 2, 2014

Yearly Maintenance. (The Bottom Bracket)

 This is the time of the year when the workshop is full of bikes waiting for their annual check up. Mixed in with the bikes that we see every year are the bikes that have just been dragged out of the barn for the first time in 5 years and were put up wet in the first place. Those bikes are always interesting to pull apart and really highlight what can happen to bikes that have suffered some neglect.

However it is just not neglected bikes that have problems, any bike that is ridden regularly and hard throughout the year desperately needs that overhaul before the new season starts. Recently we had just such a bike in the workshop. This bike is one that has been overhauled by us before, not yearly I think we did a frame up rebuild on it 3 years ago, however the bike always is cleaned and lubed on the outside by the owner and kept inside.

Below is a picture of what we found inside the bottom bracket shell, once we had used a breaker bar and 2 of us to get the cartridge out!


 Keep in mind that this is an aluminum frame so that is not rust from the frame itself that you are seeing however aluminum does create a powder like substance under the right conditions. This is a mixture of sweat and moisture that finds its way down the seat tube and also the cartridge itself being steel bodied can supply some rust to the mix as well.

Moral of this story is. "If it looks good and clean on the outside, it doesn't necessarily mean everything is cool inside..."
 
This is a bottom bracket tap. The threads were so damaged after removal we had to re-cut them. Not an ideal scenario but the only option at this point.
This is the material that was removed in the re-tapping.