April 26, 2012

A rough sketch on Bike Cad

I have been spending the past few days measuring and comparing notes on my bikes, primarily a comparison of my my current road bike and those of the measurements that I have calculated for my first custom road bike.  It turns out that my Specialized Sirrus road bike (from the early 90's) is relatively close, in terms of angles and measurements, to the bike I intend on brazing.  This reinforced my belief that the Specialized does indeed fit me quite well for a stock production bicycle.  I did change a few items on the bike such as a longer 100 mm quill stem, 42 cm ergo bars with a 90 cm reach and Selle Italia Storica saddle.  All of which seemed to dial in the comfort level dramatically.

The Specialized Sirrus has a 54 cm seat tube, 55.5 cm top tube and 42.5 cm chain stays lengths. The 72 degree seat angle and 73 degree head tube angle are not that aggressive, however the bicycle responds very well to my input.  I especially appreciate how this bicycle feels while cornering.  The chain stays are of medium length with an average bottom bracket drop of 7 cm.

I plan on building my first frame with similar characteristics.  The lug set from Long-Shen has a 73.3 degree seat angle and a 73 degree head angle.  I will stick with a standard 7 cm bottom bracket drop.  The measurements I have calculated for this bike will have a 54 cm seat tube and a 54.75 cm top tube.  The stem will be brazed at a length of 105 mm.  This is close to the measurements of the Specialized, however it will differ slightly in the length of the top tube.  Currently I am deciding between a 43 or 43.5 cm chain stay length spaced at 130 cm for a 10 speed cassette.   I am basing these calculations on the 700 c X 28's that I will be running on the new wheels and the current clearances of 23 cm tires and planet bike fenders on the Specialized.  I will need to accommodate for clearances of the 37 mm fenders while still leaving room for brake pad adjustment using Grand Cru long reach caliper brakes.

I have heard fantastic reviews of these brakes and look forward to comparing the stopping power with what I am currently using.  This bike will have a bit of a Velo Orange/Grand Cru theme as I also plan on using the Grand Cru 50.4 bcd crankset as well.  I  still have yet to decide on a saddle, seat post, handlebars and tires for this bicycle.  I have, however decided to opt for a less expensive 1" threadless headset made by Tange.  A Chris King 'nothreadset' is still the best in my books but I can't seem to justify the added price.  Martin from Hoopdriver Bicycles has placed an order for one which should be arriving within a few weeks.

I have also ordered a set of Velo Orange PBP rims laced to Grand Cru hubs from Hoopdriver.  My skills are severely lacking in the wheel building department.  Not wanting to mess around with a brand new set of rims and hubs I am having Martin build up the wheels.  Some things are best left to the experts.  I chose to go with 36 instead of 32 holes so these wheels should be bomb proof!  I'll save wheel building practice for my next build project.  For now I will practice by adjusting my poorly built machine made mountain bike wheel sets on my truing stand at home.

I drew up a quick sketch of the bike using Bike Cad on-line.  Since I do not have the headset, wheels and brake calipers in my hands yet I have not actually done any real calculations of fork length and trail given that the fork crown will have a 7 degree offset and straight blades.  There appears to be a slight possibility of toe overlap in the Bike Cad drawing, however the settings did not let me change the fork angle on the basic web application.  Since I have yet to calculate my 'actual' fork offset and trail measurement with my set up I have relied on the Bike Cad being close enough at this point.  In the event of toe overlap I might extend the top tube by a few millimetres to compensate.

Bike Cad sketch

There is something nice about being able to see a visual layout of the bike before it is actually constructed.   This is more or less how I pictured the bike in my head, although the finer details are not represented in this drawing.  

Before getting too far ahead of myself I will be sitting down at the dining room table to sketch out a 1:1 scale drawing of this build.  Having got a good idea of the overall measurements for the front triangle I will most likely start by braze the stem first before I cut and mitre the tubes for the frame and fork.  Fingers crossed, I hope to be lighting the torch in the next few weeks.  Once the basement floor is painted I can finish setting up my workshop to actually function as a work area rather than a pile of boxes and bikes hanging from the rafters.  Sadly this seems to be the one task causing me the most amount of anguish.

April 19, 2012

Dual Control Experiment

In a previous post I explored the idea of equipping the new build with Retroshift adapters and brake lever mounted thumb shifters.  The idea seems like a reliable way to achieve shifting from the hoods at a reasonable cost, not to mention the benefits of serviceability with this system. I am still curious about this setup however I  have decided to go with conventional Dual Control levers for this build.

Over at the lazy randonneur's blog, Vic has acquired a set of Retroshift equipped levers and intends to review them on his new 26" long haul trucker build.  I am in eager anticipation of his feed back as he is a reviewer who tells it like it is.  Although his long haul trucker build will not be his go to long distance bike, he is sure to be putting in some decent miles on it in the near future.  I am interested to see what these levers will be like for a randonneur as opposed to their intended cross rider market.

In my research for parts and components for my build I came across a drive train system that immediately caught my attention.  I decided early on that a ten speed double set-up is what would suit the intended purposes of this bike nicely.  Since I am building this bike from scratch and will not be transferring any components over from my other bikes, this gave me a certain freedom to pick and choose so far as my budget and my sense of aesthetics allowed.

In my attempt to keep within a reasonable budget I came across a review of microShift's Dual Control levers and derailleurs.  I had never heard of microShift before but was impressed with their line up of drive train components.  What blew me away was the price!  As far as I have read from the reviews there seems to be no lack in performance in shifting, nor any complaints or issues regarding durability.

MicroShift is an engineering company based in Taiwan and has been in production of Dual Control levers and components since 1999.  Although Sram, as a drive train component manufacturer also arrived on the scene about this time (Grip shift 1988, Sram derailleurs 1997), Sram's success with acquisitions and marketing has allowed for a greater share of the north american market.  While Shimano, Campag, and Sram have been battling for market share, microShift has come in under the radar with an attractive line up of components which might cause others to sit up and take notice.

I have since ordered a set of microShift Dual Control Levers, braze-on front derailleur, and 10 speed rear derailleur form Bike Nashbar in the US.  These parts came out to be well under the price of a comparable Shimano product.

microShift Dual Control Levers (10 speed double)        SB-R102B        $139.99 USD
microShift braze-on front derailleur                                   FD-R72-F         $ 29.99  USD
microShift 10 speed rear derailleur                                     RD-R56S          $ 39.99  USD

I plan to write a follow up review of the microShift drive train once I have finished the build and put some solid miles of wear on the components.

We are fortunate to live in an age where the modern bicycle derailleur has more or less been perfected with reliable and accurate shifting available to all models of (properly adjusted) components.  Shifting has never been better, and although companies will try and make you believe that electronic shifting will be the new standard it is still too early to tell if the market will accept the added price and complexities of these new digital systems.  Mavic, Suntour and Sachs tried early in the 1990's to convince the market that electronic shifting would be the next big thing, but failed to produce a reliable system.