Wednesday, June 30, 2010

Oh, Canada.

Hey, all you hockey pucks out can be festooned with the maple leaf if you like. This custlomer hails from up north and wanted a little symbol of his former home on his bike. The maple leaves remind me of days when folks wanted more stuff in thier paint to signify something to do with their origins. I'll be putting a couple of French flags on a frame in a couple of weeks. I'm all enthused about the whole mountian bike nostalgia going on right now. Old bikes that used to languish in garages forgotten are now sought after as historically significant rideable relics. Maybe one day even my old bikes will be collectable. Vote for me to get into the mountain bike hall of fame ( Industry catagory )and that old lobster in the garage might pay for a new refigerator.....or something.

Saturday, June 26, 2010

Anatomy of a build

The customer for thos scandium 'cross frame requested a pictorial of the assembly process. I'll share it with all of you who check out this blog on occasion. Granted , this isn't every last step but given the time I had, it shows most of the process. Below is my drawing table with the plan for the frame well under way. I do a full-scale drawing for every bike-no autocad here , just your basic drafting equipment and a bevel protractor to accurately find the angles.
Here you can see that the drawing is finished. I made a correction to it-that's why there are some extra lines where the top tube is pictured. Having a full scale drawing makes it easy to chek the work as I go along. If the something dosen't line up with the drawing, Iv'e got a problem to solve.

Here's a photo of the boring operation on the lathe. I remove a little material from the head tube to make it a little easier to weld and later machine for the headset. I only have 50 amps in the shop so if the material is too thick , I can't get good weld penetration.

Here's the first weld-seat tube to BB shell. I always start here. I don't have to but it seems the logical place to start as it is pretty much the center of the frame.....all tubes project outward from this point, more or less.

I lay out the complete tubeset on the drawing table to make sure the tubes are the correct length to be used in this frame-too long and I'll cut off the butting and not have as strong of a bike in the end.

This is the final turning operation on the head tube. I take a small amount of material off the outside and leave a 'collar' at either end of the head tube. I like the way it looks and it puts more material where it is needed in the higher stress zones.

I weld the finished head tube to the top tube early in the process. If I make an error in the head angle , it will be easy to check at this point ans start over if it is too far out of spec.

This is the mitering process being done on the front end of the down tube that will meet the head tube at approximately 60 degrees. All the main tubes and stays are cut this way if they are to be welded to another tube.

This is my home-made main triangle jig with the seat tube, BB shell and downtube held in place for welding. I'll tack the down tube in three places, then remove the assembly from the jig and do all the weld passes. When this is done the main triangle will be in two pieces, this one and the head/top tube sub-assembly.

Here's the front triangle all welded up sitting on the jig.

When the fron triangle is aligned, I check it against the drawing to make sure it's correct. At this point I can use the drawing to orient my rear-triangle jig which bolts to the seat tube.

Here's the rear triangle jig being used to hold the dropouts and chainstays for welding. I leave this jig on the frame until all the stays are fully welded on.

Once the rear triangle is welded up I go through an alignment stage, doing the final check with an appropriate rear wheel and a Park frame alignment stick. It's pretty basic but it tells you all you need to know about inaccuracies in your craftsmanship tht need to be addressed.

Here's the final product laying on the drawing and hooray ! It all lines up as it should. There are a lot of little steps that I didn't get a chance to photograph but this is my first attempt at showing how a frame goes together in my shop. Some day I'll produce a DVD if I have the time.

Monday, June 21, 2010

Cross frame for the guy that revolutionized west coast racing

Originally, cyclocross in California and elsewhere was kind of an obstacle course torture track that only circus performers could master . This style of racing, though amusing for spectators bared no resemblance to European cyclocross racing. About 15 years ago, a fellow in Santa Cruz who was helping the local promoter set up courses noted that the races were not wery well attended and there were some pretty bad injuries as a result of the "Jungle-cross" courses. This man was and is Jeff Clark. Jeff did a bit of research and discovered that cyclocross in the classic sense was a much faster, flatter type of racing that didn't involve river crossings, scrambling over fallen redwood trees five feet in diameter or jumping drainage ditches eight feet wide and four feet deep. Jeff proceeded to change the course designs for the Surf City cyclocross series and the result was an increased amount of participants and spectators. Not only that, the local racers started doing better on the national scene and some even went and raced in Europe with some success. I feel that everyone who currently races cyclocross and enjoys it owes something to Jeff Clark. I built him the best frame out of the best set of materials I had in my shop. This is the result. I only had one of these tubesets left and it might be a year or more before I see another one. I can think of nobody more deserving than Jeff as ironically, he has been to hundereds of races as a course manager but only now is thining of racing. Maybe this frame will help make it fun , just like Jeff's influence has made 'cross racing fun for hundereds of racers, including myself.

Friday, June 18, 2010

Tig team s.l. 'cross, 2010 version

I started building this model in 1992 and it was my first tig welded 'cross frame. The ability of the frame and fork to take large tires made it instantly popular and it pretty much put me on the map as a builder of useful and lightweight cyclocross frames. This version is the latest, even though the fork is a bit of a throwback in style. The flat-crown fork actually has more tire room than a unicrown and isn't much heavier. This frame will mostly see commute duties between Sacramento and Davis, California.
Back in 1992 this frame would have single bend stays and horizontal dropouts. Now i have the ability to put a little more style into it with the s-bends matching up on all the stays. I custom bend the seat stays so that the tire room is adaquate and the cantilever bosses are where they are supposed to be for optimal brake setup and function. This is the stuff i was winging back eighteen years ago.....I guess I got lucky most of the time.

Tuesday, June 15, 2010

an oldie for sale

This isn't one of my very first but it is one of the first 20 tig welded mountain bikes I have made. It dates from 1993 and is serial number # 0017. I built it for a friend's wife who recently upgraded to a full suspension bike. There ins't enough room in the garage so its time for the old one to go. Some parts are original, some not. There's a first generation 1" steerer Judy on the bike that still works.....amazing. The shifters and rear hub are 8spd XTR with the bulk of the rest beint XT. There's a set of diacompe v-brakes and levers. The bike has one of my custom stems....kind of a rarity. Asking price is $ 450. The right shifter is a little messed up but apart from that, the bike is in very good rideable condition-the wheels are dead straight. Call me at the shop for more details. The frame is small, good for a 5'4" rider.831-429-8010

Saturday, June 12, 2010

Scandium CX frame for Nor-Cal

The customer for this frame said that he had primarily an MTB background , so I put a 44.5 MM downtube in this frame so he could ride it down some rocky trails when not racing . I am using the new Easton Scandium that I purchased last summer for the top and downtubes in my team bikes. This stuff is pretty light but it is genuine Easton tubing and I trust it more than other stuff of a similar nature. We'll see how it holds up to the Bay area 'cross series in a few months.

An old one comes back home

This bike was bought on craigslist for $ 500. Although it was missing a few parts, it was still a very undervalued bike at the price. As it turns out, this one was ridden to many wins and possibly a national championship by Bobby Walthour III. Bicycle racers frequently have financial ups and downs that make for the need to purge the herd periodically. That must have been what got this bike into the open market. Today it is owned by someone well aware of the bicycle's heritage. The owner brought # FA-008 by the shop for me to see. Now you see it as well , rescued from the streets of San Fransisco.

Tuesday, June 8, 2010

Where's the beef ? Take a look at the stays....

A local customer who I built a big-tire road frame for in 2007 ordered this frame. It is essentially a Pegoretti style welded steel frame. The chainstays are Prestige samples, the seatstays are U.S. 4130 aircraft cro-mo.The only dorpouts that would accomodate these large tubes were these Paragon hooded style. The rest of the tubeset is Columbus Spirit oversize tubing. The frame weighs about 3 lbs. 14 oz. , not bad for such a beefer. This customer was toughtful to give it room for Continental 700x28 tires to calm down the ride a little. It will be interesting to see how it rides.

Wednesday, June 2, 2010

Cycle speedway bike for the U.K.

Ever hear of cycle speedway ?- Niether had I. I guess the closest thing to this sport ever to happen in the U.S. was "Formula-one" , an ill-fated attempt at a new dirt bicycle race. Cycle speedway on the other hand has had a pretty long life in the U.K. and in Europe as well. Check it out on's wild. Super short track and lots of bumping in the corners seem to be what the sport is all about . This odd looking frame is what I was asked to build. The headtube is way short.....but not quite as short as the customer asked for ! I had to take a little poetic license. The bike will not have tires like this but some 1.5" slicks. There will be no brakes of any kind on the bike and it will have a single freewheel only. How do you slow down ? Just put your feet out and wait. Besides, it's all about speed and caveman simplicity.....brakes just slow you down.