Friday, June 3, 2011

Steve's Race Bike...2011

It's been a brutal few weeks, with some long stretches of time at the fire department...last stint was five days straight before I was paroled to come home.  The family life has been suffering as I've been absent a lot.  Fortunately, I was able to spend the last two days at home and in the shop, taking a break to do some grilling so we could have a family meal together, that was nice.  The weather has finally turned sunny, and so to have my spirits.  Helps so much when the day starts with a smile.

A project that was suppose to be done in February were the team bikes for the 2011 season. Suffice it to say, I did not get them done and one of Steve's big races is tomorrow, so I put the hammer down and built his race bike so he can totally dominate at the Mohican 100k in Loudenville :)

Nothing special, just a 29er hardtail with chainstay mounted discs, curved and ovalized top tube, and curvy rear end painted in a white with gold pearl clear coat.  Throw in a 28" Luv and a Disco Stick ti post and we have a fast looking bike.

Mitering the down tube...I mark each cut profile so that I can trim the tube to the closest possible length before heading to the mill to save a bit of machine time.

The front triangle fitted up.  The top tube is rolled in a ring bend press with an ovalized die just for this application...
I caught a thread on MTBR's frame forum discussing frame alignment and subsequently, welding in a fixture.  I've always welded as much of the frame in the fixture as possible, designing my fixtures for the greatest possible access while maintaining rigid and accurate contact points (headtube, bottom bracket, seat tube, dropouts).  There is no substitute for an accurate, repeatable fixture, as it creates a solid foundation to build off of, and limits the required alignment necessary post welding.  Typically, the only change I need to make once it comes out of the fixture is to spread the rear dropouts a millimeter or two dependent on how much heat I put into the stay braces.  Everything else is dead nuts straight, just how we like it.

Although some areas are tight to get into, almost the entire frame is accessible.  Here we area hitting the underside of the head tube...


Out of the fixture now, you can see the only area I still need to weld is the crotch on the left bottom bracket side.  To do this, I use an internal heat sink to protect the shell from deformation...

All tightied up...
Steve wanted a "sexy rear end" with lots of curves, so I custom bent up these stays to be quite shapely...


Brazing the dropouts to the stays, fresh out of the torch. A quick soak and a touch with the Dotco and I'll have nicely finished scalloped ends...

The side profile shot; next are braze ons, media blasting, and then off to paint.
Steve showed up last night with a mix mashed box of parts that we slowly put together into the "mongrel".  As with most last minute projects, rarely does everything go as planned.  Last night, the rear brake line was too short so he's now running a front xtr and my rear Magura off my single speed.  We had to do some modifying of the front derailleur to get the throw we desired, and he's running (by choice) a SRAM front shifter/derailleur and XT rear shifter/derailleur...in a 2x10 configuration. The best of both worlds?  We'll see how he does Saturday  :)

The really crappy 0100 in the morning cell phone shots...
It was a blistering pace for the last couple of days.  Working on finishing a few tye dye bars for Koh (which have turned out to be a lot harder than anticipated) and then putting on my dress blues to serve in the Honor Guard for the opening cerimonies at this weekends Cancer Relay for Life.

cheers,

rody

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