Wednesday, February 25, 2015

Joe's Bike

Four years to the day tomorrow, I blogged about Joe's road bike after building it for you.  Four years ago, Joe was 76.  After 4 years and thousands of miles and a joint replacement or two, Joe couldn't swing his leg over his bike to ride.  He came in looking for a new bike with a step-thru frame.  While there are plenty of step-thru bikes on the market, they are all pretty much heavy, non-inspiring comfort or hybrid bikes.  Nothing that could easily converted to a bike that offers a spirited ride.  Well, there was one that I knew of that could fit the bill.  Soma Fabrications make a pretty nifty mixte framed bike called the Buena Vista that would be an easy convert to drop bars like Joe likes.  

Buena Vista ordered, arrived, built, call to Joe - "that looks fabulous!"  Take it for a spin, Joe, let me know what you think.  And that's where Joe's limited flexibility showed itself.  Even with the lowered top tube of the mixte design, it was still too high for Joe to lift his leg over.  Back to the drawing board.  

"What would you think about cutting the top tube out of your road bike and welding in a new "top tube" as low as possible, Joe?"  Joe liked that idea as it used everything he already had and didn't generate excess.  Now I just had to figure out how to get it done.  A call to Cameron Falconer, fresh off my recent MUSA disc cross frame production to discuss the possibility of converting Joe's frame and because Joe's 80 and still rides a bike and loves riding bike, Cameron agreed.  We talked about cable routing, how low the tube could get, and to work Cameron went.

The result?  According to Joe, it's fabulous.  I did have to move the seat tube bottle cage to a place high up on the new tube with a Two Fish cage adapter.  As I was riding to work one morning last week, I saw Joe pedaling towards me.  As we passed, I asked how was the bike.  "Fabulous!"  And away Joe pedaled.  

Yes, the bike is a bit flexy, but for Joe and his riding style, it's perfect.  Ride on, Joe!

Post script - this was the first and last step-thru conversion from Black Mountain Cycles and Cameron Falconer.

(What's playing:  The Jayhawks Baby, Baby, Baby)

Friday, February 13, 2015


Long before Enduro™ was a thing, there was a company named Enduro selling bearings.  Good bearings.  One of my favorite jobs to perform on a bike is replace old, worn out bearings in hubs and bottom brackets.  The difference is immediate.  There's nothing quite like transforming a dried out, crusty bearing that barely spins and crunches in your fingers into a smooth spinning part.  

Up until recently, if your Shimano Hollowtech II bottom bracket wore out, your choices for a new bottom bracket were either another Shimano or a Chris King with a hefty price jump.  Basically, you had a choice between replacing your worn out bottom bracket with the same thing for about $30 or $40 or dropping about $150 for a King or other pricey, but good, bottom bracket.  

My preferred method to deal with worn out Shimano bottom bracket bearings was to remove the offending bearings and press in new Enduro bearings.  Enduro make a nice kit for performing this task - two new bearings and a nice dust/dirt shield.  The bearings Enduro used to replace the Shimano bearings are slightly larger since they don't use the plastic sleeve that fits into Shimano's bearings.  Bigger bearing means they should carry a bigger load.

For about twenty bucks in parts and another thirty to forty in labor to remove cranks, bb, press out old bearings, press in new bearings, reinstall cranks, check can have a sweet smooth rolling crankset and not have to have to dispose the entire bottom bracket unit.  Reuse the cups and center sleeve and keep on pedaling and have a better bottom bracket.

I was reminded of how much I like this fix when a bike came in for new chainrings and chain last week.  After removing the chain, I marveled at how smoothly and easily the cranks spun.   Give them a spin and they spun round and round and round and ...  They spun around a lot.  I then remembered that I had replaced the bottom bracket bearings with Enduro bearings quite a while ago and they were still fresh as day one.

I also recently discovered/realized that Wheels Mfg. had produced their own bottom brackets with prices that sit comfortably between Shimano's and Chris King's.  For $55 you can get a new bottom bracket that is assembled with Enduro's radial ABEC-3 bearings and for $75, you can get their bottom bracket assembled with Enduro's angular contact bearings.  Twenty bucks is a good upgrade to get a bottom bracket with angular contact bearings since they are better at resisting a side-load - and it's very common for Shimano bottom brackets to be overloaded from the side when the left arm crank arm fixing bolt is overtightened.  That act is probably the main reason why Shimano Hollowtech II bearings fail prematurely.  The Wheels Mfg. bottom brackets are a new addition to the shop, because they work great and offer a nice option on a new build or repair job.

"DO NOT DISASSEMBLE" - yeah, right.


A fresh Enduro bearing ready to be installed

Enduro bearings still like new after miles of off-road riding.

Or if you're starting from new, this $75 Wheels Mfg. bottom bracket with Enduro angular contact bearings is a great choice - and it's made in the USA.  Shot doesn't show the included secondary shield.

(What's playing:  The Byrds Hungry Planet)

Monday, February 9, 2015

Tandem From ... Part 2

Yesterday, I put up the post about the Actos Machine tandem build focused more on the drivetrain.  Besides the R601/R603 cranks, it got new Ultegra 6700 shifters and derailleurs and an XT 11-32 cassette.  The shifters were installed on a set of Ritchey WCS carbon bars.  The Ritchey WCS stem was fit to a quill stem adapter (1" threaded fork).  The rear bars are Fyxation time-trial style bars in 25.4 to fit the titanium adjustable stoker stem.  A SRAM red aero bar brake lever operates the cantilever drag brake.  The red color lever is a nice touch/match to the red King hubs and red vintage Salsa quick releases for wheels and seats.

Part 2 will mainly deal with the rear chainstay mounted WTB Speedmaster roller-cam brake.  During my work on the bike, a friend who used to work at the old Point Reyes Bikes, where the bike was originally sold and built, recalled having had plenty of issues with the rear brake when building it originally.  The one thing about the rear brake that stood out to me was that there was minimal clearance between the cam and the bb shell.  There was no cable guide.  The shift cable, originally, ran across the bb shell without a guide (there was a large thin washer between the drive side fixed cup and the bb shell.  I assumed this to be to keep the guide-less shift cable from migrating off the bb shell to the right.  Maybe this was okay with the previous drivetrain, but this new 10-speed set-up would need to be a bit more precise.  

I decided the rear shift cable needed a guide to keep the cable from moving across the shell.  I modified a Shimano guide by cutting off the front derailleur cable guide and thinning out the guide to make it as low-profile as possible and installed it as far to the right as it would fit to allow space for the cam.  

To address the issue of the cam hitting the bb shell when the brake was applied, I dug back into a bag of tricks I learned long ago.  Dug deep.  WTB roller cams use a stainless bushing that fits on the brake post.  Then the arm with the pressed-in bronze bushing slips over the bushing and rotates around the bushing.  The arms also have a Grease Guard™system where grease can be injected into the side of the arm and then runs around a groove on the stainless bushing, thereby greasing the pivot and making it rotate smoothly. 

Years ago, I recall needing to modify another WTB roller-cam by pressing the arm onto the bronze bushing in a different location.  When moving the arm on the bushing, you lose the ability to push fresh grease between the bushing and stainless pivot - unless you make a new groove.  Making a new groove requires relocating the bronze bushing first, redrilling the bronze bushing, and making a new groove in the stainless pivot.  Easy.  But slightly time consuming.  

The brake is in the stock position.  The hole in the side of the arm is where grease is injected.

The arm relocated on the bronze bushing - gaining critical clearance for the cam to pull.

Yeah, that's going to work nicely.

I drilled the hole through the bronze bushing with the stainless bushing in place to see where the new groove had to be located - see the tiny divot above the stock groove.

I used a hacksaw to cut a small, shallow groove around the circumference of the pivot to serve as a guide where a deeper groove had to be made.

A Dremel tool was (lightly) fixed into my vise with a small round grinding bit.

More detail of the Dremel grinder and where the groove will be.  This is before I cut the groove deeper.

The old groove and the new groove.

Brake all buttoned up.

Tools used to modify the brake.

With the rear derailleur cable guide installed.  The front derailleur cable runs around the bb shell through a piece of cable liner.

New clearance for the cam.

Arm clearance on the right side...

Arm clearance on the left side.

Brake arm in its new location on the bushing.

When the bike was originally built, the brake bridge must have been redrilled to lower it.  I didn't like the look of the second, unused hole, so the bridge got trimmed giving it a cleaner look.

All done!

(What's playing:  Gang of 4 I Fled)

Friday, February 6, 2015

Tandem from ... Part 1

Only a couple years in the making, this Arctos Machine titanium tandem made by Merlin co-founder, Gary Helfrich, is owned by a local resident.  I'm guessing it was made around 1990 and had most of the original parts on it when I brought it into the shop a couple years ago.  The task was to install modern road components, converting it from a flat-bar bike to a drop-bar bike.

Because one of the parameters was a triple crankset and integrated brake/shift levers, that narrowed things down to Shimano.  The R601/R603 cranks are an interesting design.  The stoker's crank is mix of Ultegra 6700/Dura Ace 7900 aesthetics combined with an axle design like the XTR 970.  A kind of Octalink/Hollowtech design.  This is where I ran into problem #1 and #2.

Problem #1
The stock front eccentric bottom bracket is not threaded, it utilizes pressed in bearings and square taper axle.  This requires a new eccentric bb.  Problem #1a - the diameter of the eccentric is a one-off part and does not match any available eccentric sizes - by a long shot.  From my product development days working with Taiwanese vendors, I knew that Tien Hsin/FSA made several eccentrics of various sizes.  I found one that was close (a little oversized) and sourced it from Taiwan.  With frame and new eccentric in hand, I headed to Petaluma, CA and the shop of Sean Walling's Soulcraft Cycles where he chucked it up in his lathe and turned it down to fit perfectly in the old frame.  Big thanks to Sean.

Back at the shop, new eccentric installed, time to install the cranks.  (Expletive and problem #1b)  The stoker's crankset  chainrings don't clear the chainstays or the rear, chainstay mounted WTB Speedmaster roller-cam brake.  Hmmm.  Don't panic.  The stoker crank design is such that it requires spacers (supplied w/crank) under the left arm to set the arms just so against the bearings.  Instead of installing the spacers under the left arm as the instructions dictate, I installed some under the right arm and some under the left arm to get me the chainring clearance needed on the right side.  There was still an issue with the left side, but it's way easier to deal with this issue on the right side.  The right side was dialed and chainline was still ideal - the left side, however, problem #1c.

Initially, the problem with the timing chainrings was the chainring bolts were a bit too close (touching) to the brake arm.  A combination of filing a bit of the corner off the chainring bolt, changing the 42t rings to 38t (the smallest that will fit to a 130mm bolt circle), and filing a bit of the brake arm got everything to play well together with good clearances.  


Making clearance with the file

Some of the tools used to get the cranks installed.

No clearance here - time to improvise.

The original eccentric used a double bearing on the left side - good idea.

Filing the brake arm for clearance

Checking clearance - only want to remove just enough.

The 38t rings helped, but not enough.


Clearance, Clarence.

Stoker operated drag brake cable routing

The bike also got a new wheelset build with Chris King hubs with a stainless drive shell.


All should be good to go, right?  Wrong.  Problem #2 rears up, but that will be in Part 2, which I'll try to get to soon as it's deserving of a separate post.

(What's playing:  Blondie Dreaming)

Tuesday, February 3, 2015

What's In The Stand: WTB Phoenix

Yes, another Steve Potts made frame.  This time under the Wilderness Trail Bikes badge as a revered Phoenix.  It's pretty much known that the Phoenix is one of the best riding mountain bike frames on the trails.  It's always been my goal to make a frame I design disappear beneath the rider.  A frame that requires no super-conscious effort to pilot.  The Phoenix does exactly that.  

This is an early 1" steerer tube Phoenix that's been repainted.  It's purpose is to be a rider - a real, daily rider.  Back when the Phoenix was offered, an option on the frame was for a press-in, Grease Guard™ bottom bracket.  I know most shops would look at the frame's bottom bracket and say "hey, there's no threads here, you're frame is ruined."  I know that the threads were blown out with a purpose-made reamer that allows a 6003 bearing with a 17mm diameter axle to be pressed in place.  The tell-tale tiny hole drilled into the bb shell approximately 7mm inboard tell me that Grease Guard™ bearings were installed into the frame at one time.  The difference between a standard 6003 bearing and a GG bearing is that the GG bearing had a groove machined into the outer race that allowed grease injected through the holed drilled into the frame to fill the bearing and purge out old grease, thereby prolonging the life of the bearings.  The system worked.  It worked real good.

However, Grease Guard™ bearings are no longer available, so a standard 6003 Enduro bearing was called into duty and pressed into the frame with a Phil Wood axle.  It's a great system.  The 6003 bearings are large and support the bearing very well.  With all of today's large diameter axle, thin PF bearings that creak and don't last even a ride season, the old 6003 system that was also used by Klein is a smart design.  I'm a fan.  

Ready to ride

An old set of Klein bottom bracket tools was called into service to install the bearings and axle.  

You can see that the threads have been reamed out.

Ready to go!

(What's playing:  "Living Famously" - Keith Moon)