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Design

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Design Concept

The bike has been design as a road bike, more specifically a racer. I wanted a bike that would suffice as a decent bike for road riding and the odd sportive event (such as the Wessex 100). For touring and winter riding, I will keep the old faithful Claud Butler. The new bike will probably be also used with the turbo trainer during the winter season because I am a bit of a fair weather rider! Because I had no plans for winter riding or touring with this bike, there was no need include any facilities for racks or mudguards in the design.

The picture on the left is in fact a link to a 3D model of my bike design. This is available in two versions: low res (1.27Mb) and high res (3.27Mb). These open in Adobe Acrobat, and allow you rotate the bike into any viewing angle. The low res version includes the bloke (my height), but the high res version has a lot more detail (individual spokes etc) and includes its own guided tour of the bike with my comments. This will only work on Abobe Acrobat version 7 and later (download latest version here).

The frame was mostly TIG welded using a 17-4 PH filler rod produced by Weld Mold in the US. The dropouts, braze-on's, head tube inserts and seat stays were silver soldered using an Argo-braze™ product from Johnson Matthey, which hopefully will not discolour like other silver solder products (to date there has been no discolouration).

Geometry

To determine the frame geometry I used a number of applications, compared the results, and also looked at the geometry of some production bikes that I have ridden. I used Accufit, Tim Patereks' program and the Competitive Cyclist fit calculator to help determine the best geometry. However, all of these tools gave different results, so I ended up using my judgment combined with my own experience to determine the final geometry. As it happens, the bike is a very good fit, but I think it would have been useful to have a proper fitting session with a professional, or to build a bike fitting jig.

Frame geometry
Dimension Value
Horizontal Top Tube Length C-C 557mm
Head Tube Angle 73°
Seat Tube Angle 73.5°
Chain Stay Length 411mm
Seat Tube C-C 540mm
Fork Rake 43mm
Bottom Bracket Drop 67mm
Head Tube Length 148mm

Frame Components

The Reynolds 953 parts list includes many different tube diameters, wall thicknesses and profiles. It is down to the frame designer (me in this case) to determine the best frame component for each application. I selected some of the thicker gauge and larger diameter tubes for added strength to compensate for my, perhaps less than perfect welding, and the excess pounds about my person. The seat tube that I originally ordered and received was incorrect and Reynolds replaced it for an alternative design (in fact the same tube without the swage to reduce its diameter). The original seat tube was tapered from Ø31.75mm (OD) at the bottom bracket end to Ø27.2mm (ID) at the seat end to suit a standard diameter seat post. Unfortunately on inspection, the length of tube at the seat post diameter was insufficient to adequately secure the seat post without it tending to rock inside the seat tube. This was due to a manufacturing problem at Reynolds (caused by the strength of the material). I now use a shim insert in the seat tube to allow the use of a standard seat post (I also have the option to use a larger non standard seat post).

Frame Components (Reynolds 953)
Part No. Diameter mm Wall / mm Length mm Butt Profile / mm Weight / g Qty ordered Description
SS4020A 28.6 0.55 / 0.35 / 0.55 625 120.50.320.50.85 190 1 Top tube
SS4210A 34.9 0.6 / 0.4 / 0.6 680 40.40.420.40.140 267 1 Down tube
SS4703A 31.75/27.2 id 0.6 / 0.3 / 0.6 635 100.75.215.75.170 226 1 Seat tube
SS4140A 31.75 0.6 / 0.3 / 0.6 635 100.75.215.75.170 226 1 Seat tube
FS4520A 17/29 oval 0.7 / 0.5 410 Taper to 15mm tip in 953 139 2 Chainstay
HS4400A 38.1 0.7 200 Parallel 129 1 Head tube
GS4602A 19.05 0.55 580 Taper to 13mm tip  144 2 Seat stays

The frame fittings were a bit of a no brain-er, because there wasn't a lot of choice for these bits. I could have purchased some non-Reynolds 953 components separately, but didn't much see the point of that. One exception to this was the STI braze-on's (gear cable adjusters on the downtube). These parts as manufactured by Reynolds were a little disappointing due to the complete absence of any base to spread the load on the downtube. Alternative stainless steel adjusters were purchased separately from Ceeway.

Frame Fittings (Reynolds)
Part No. Name Description Pack size Mat'l code Qty
LS100A BB Shell Ø38.1mm OD, thread 24TPI, 68mm wide EA 953 1
LS170A Rear Dropouts(PR) 7mm wide at QR/axle, 4mm at C/S tip = 15mm, S/S=13mm Set of 2 953 1
LS200 Cable guides Standard design EA 901 3
LS210 STI bosses Reynolds components not used - see text Set of 2 901 1
LS245 Head tube inserts Ø34.mm ID Set of 2 901 1
LS250 Brake bridge Standard allen key fit EA 901 1

Other Components

I chose Shimano's 105 groupset, which is Shimano's mid range road groupset. In 2006 Shimano introduced a 10 speed version of the 105 groupset which means as parts wear out I will be able to mix and match groupset components with Ultegra or Dura Ace (top of the range) components. By selecting the triple version of the groupset, I will have the possibility of changing the chainset from a triple to a compact (not so easy if you have a double).

Other Components
Name Make Model Details
Chainset Shimano 105
10 speed
triple groupset
FC-5603 172.5mm 30/39/50
Chain CN-5600 10 Speed
Rear derailleur RD-5600 GS Long cage
Front derailleur FD-5603 Triple, band type
Brakes BR-5600  
Cassette CS-5600 12-25T
Levers ST-5600  
Computer Shimano SC-6502 Flightdeck
Pedals Shimano PD-A520 SPD Compatible
Wheels Mavic Aksium  
Forks Columbus Carve 43mm rake
Tyres Vitoria Open Corsa Evo-KS 700 x 23mm
Saddle Fizik Pave Ti  
Headset Cane Creek S-3  
Bars ITM Super 300 440mm
Stem ITM Forged lite 110mm

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