Showing posts with label SRAM. Show all posts
Showing posts with label SRAM. Show all posts

Tuesday, 4 April 2023

Bike Project: 2012 Tomac Flint 29 (29er XC to Dropbar Gravel)

2012 Tomac Flint 29 gravel bike
2012 Tomac Flint 29 Gravel Conversion



THE BACKGROUND STORY:

My favourite cyclist of all time is John Tomac.  The choice may be surprising as I have always been more of a roadie, but John Tomac in my opinion is a singularly unique talent in the world of professional cycling.  Tomac either dominated or excelled at multiple cycling disciplines (BMX, cross-country, trials, downhill, and yes, even road) throughout an amazing career. Very few can claim his combination of winning with such an incredible level of versatility.

Unfortunately, the branding of his iconic name has not been as successful or enduring.  The third attempt at Tomac-labelled bikes occurred between 2006 and 2013; higher-end bikes were designed and produced under the auspices of Joel Smith (formerly with Answer/Manitou) with direct input from Tomac himself. The bikes generally garnered stellar reviews but failed to find a lasting place in the competitive market.  The iconic name has languished in limbo ever since.

Recently, I was pleasantly surprised to find a Tomac Flint 29 bike frame show up for sale locally. While not rare, Tomac bikes are at least relatively uncommon. Even better, the original owner let the near-mint frame go for a song. Score!!!  This 29er XC frame was the 2012 version and had a standard threaded bottom bracket lacking the earlier Bushnell eccentric bottom bracket system (for singlespeed option).  The AN6 aluminum custom-butted tubing results in the frame weighing a claimed 1400 grams.  I like the look of the white pearlescent paint an awful lot, but I'm not sure if it will stay looking nice for very long.


                                                      2012 Tomac Flint 29 gravel bike2012 Tomac Flint 29 gravel bike2012 Tomac Flint 29 gravel bike                                                  
2012 Tomac Flint 29 gravel bike
1. Sweet head tube badge          2. Downtube sticker          3. Signature of a legend          4. Frame & aftermarket rigid carbon fork

In homage to a classic Tomac-esque move, I decided to convert the XC 29er into a dropbar gravel bike.  I had been riding a budget garage-build dropbar hybrid rig on gravel up to this point.  The process, however, was not without its hurdles. Primary among the issues was the choice of crankset and creating an acceptable chainline.  I had originally hoped to run an oversized integrated spindle 2X crankset using a 110 BCD, but the 73mm BB shell and the very wide chainstays ruled out any road or gravel crank with a ~110mm spindle. Conversely, if I used a MTB crankset with a ~120mm spindle, the 104/64 BCD would not have the chainring sizes I wanted.  The options were to run 1X (which I didn't want) or to run either an interchangeable spider or a DUB crankset and bottom bracket (not in my budget).  I dug deep in my bins for a third option, using a Shimano cartridge bearing square taper BB with a short 107mm spindle and a dog's breakfast of a crankset (Truvativ Touro cranks with a Surly 46T big chainring and a Race Face 34T small chainring).  The frankenstein combo works, but I may switch to a DUB when money and opportunity allows, possibly running a 46/32T.


Chainring / chainstay clearance

I paired some SRAM Red 10-speed brifters I had kicking around with some SRAM X7 MTB derailleurs for a mullet shifting system.  I would have preferred the X9's if only just for the rear clutch mechanism, but beggars can't be choosers.  The front derailleur clamp butts up against the lower seat tube water bottle rivnut and can't be raised any higher; this normally wouldn't be an issue but as Surly chainrings seem to have fairly tall tooth profiles, the front cage just barely clears the 46T. Everything else works pretty much as expected.  The build weight as completed sits at a respectable 11.6 kg.  If I put on some better than entry-level wheels and went tubeless, I could easily shed some weight, but I'm happy with it for now.  I will get back with some feedback once I get a few rides in.


PHOTO GALLERY:

2012 Tomac Flint 29 gravel bike

2012 Tomac Flint 29 gravel bike2012 Tomac Flint 29 gravel bike


SPECIFICATIONS:

Frame: 2012 Tomas Flint 29 (size M), AN6 custom-butted aluminum. Serial # FAT11E0024
Headset: FSA
Fork: Generic aftermarket full carbon rigid, suspension-compensated
Seatpost: Generic carbon, with a 30.9 to 27.2mm shim
Saddle: Synchros
Stem: Kona 50mm
Handlebars: Easton AX70
Brifters: SRAM Red (10-speed)
Front Derailleur: SRAM X7
Rear Derailleur: SRAM X7
Brakes & Rotors: TRP Spyre (160mm)
Bottom Bracket: Shimano UN-52 cartridge square taper, 107mm spindle
Crankset: Truvativ Touro w/46T Survey, 34T Race Face
Chain: Shimano CN-6701
Pedals: Time ATAC Alium S
Wheels: Giant GX28
Cassette: Shimano CS-5700
Tires: WTB Nano 29 x 2.1
Build Weight: 11.6 kg


RIDE REPORT: Pending





N1+1



Sunday, 6 April 2014

Bike Project: 1995 Kona Muni-Mula "The Colonel Mustard"

1995 Kona Muni-Mula = "The Colonel Mustard".  The idea was to build up a minimalist 1X quick and dirty commuter for short distances and flatter conditions, with parts I had just kicking around.  Yet another garage build, but I wanted to adapt an MTB SRAM Grip Shifter to work on drop bars just to see if it could be done (and yes, I'm aware the original Grip Shift back in '87 was a road bike product).  Normally, I would run a bar-end shifter in this situation, but this was just a experiment to create a working bodge.












Frame: 1995 Kona Muni-Mula 7005 aluminum frame 18"
Fork: Ishiwata EX triple-butted cro-moly rigid fork
Headset: Kona Impact
Seatpost: Kona Race Light
Stem: No-name (with a quill-to-Aheadset adapter)
Bars: Cannondale/Coda
Shifter: SRAM Gripshift ESP 5.0
Rear derailleur: SRAM ESP 5.0
Brake Levers: Shimano 105 SLR non-aero brake levers
Front Brake: Shimano STX cantilevers (with Kool Stop red compound brakes shoes)
Rear Brake: No-name red anodised cantilevers
Crankset: Sugino with 42 T (Specialized StrongArm clone with added spacers for chainline)
Bottom Bracket: Shimano UN-51 sealed cartridge
Rear wheel: Sun Rims Rhyno Lite rim, Shimano Deore freehub, Shimano 11-32 T 8-speed cassette
Front wheel: Mavic rim, Shimano Deore LX hub
Tires: Specialized Fat Boys 26 x 1.25" (100 PSI) road slicks
Chain: Shimano HG
Saddle: Rocky Mountain (not pretty)
Pedals: Wellgo








The frame had a nice dent on the top tube.  The previous owner mumbled something about a roof rack, a garage, and her idiot husband.  But I picked it up on the cheap, and it was otherwise aligned.  Cosmetically not pretty, but damage to the top tube is less crucial and should be structurally safe enough for road use.  I think it gives the bike character.












Who remembers the old Scott-Mathauser Superbrakes? Their brakesets used repackaged Modolo brake levers with the cable run coming out of the bottom between the lever body and lever blade.  I figured out a way to run the housing out through the lever blade of a non-aero SLR brake lever. This was a less tortuous route for the cable, and created less friction.











I was planning on using an aluminum sleeve, but found a 3/4" poly plumbing coupling was an easy solution to adapting MTB Grip Shifts to drop bars. Cut off the ridges on a side, and the cut end inserts nicely into the ID of drop bars.  I've got nothing against glue, but I trust mechanical interference a whole lot more, so I fitted a small steel press-fit pin.











RIDE REPORT:

This little machine proved pretty fun!  The slicks blew away all those peeps still riding fat knobbies to work, and the wider 8-speed gearing with allowed me to thumb my nose at those trendy single-speed or fixed-gear hipsters once the road goes a bit up, or a bit down (which it inevitably must).  26" wheels are really agile for those circuitous routes where cutting through back alleys, parking lots, and strip malls are de rigeur, with the occasional bunny-hop over curbs and railway tracks thrown in.

I had my fun with it for a bit blasting through my part of the urban jungle, then sold it as a trusty transporter to a deserving starving student.

N+1-1.

(2014-04-05) 

Blog Archive

Followers