SPRINGS…cause it’s spring!

Ask anybody that has studied physics about springs. They’ll tell you about Hooke’s Law, the linearity of coil springs, and brush them off as the most simple topic. They probably got great grades. Some of them probably got masters degrees or PhDs. The problem is is that they don’t know what they are talking about … Read more

One more for the road; Sweet Jesus!

It’s happened again… I joined up with the guys at Firefly Bicycles to get another dropout done. This time it’s for road bikes. Firefly makes a lot of extremely elegent and fast road bikes. The craftsmanship put into them is borderline obscene. The pride the owners of these bikes take is about the same. Any … Read more

Aaron Gwin @ Fontana City Nationals

I was at the Fontana City Nationals this weekend. A great venue and a great event. Aaron Gwin was in the house during Saturday’s DH practice. I got to meet him and take some pictures. He’s a pretty low key guy. He didn’t race on Sunday. The bike was essentially stock other than the obvious … Read more

…and it begins again.

Chips are flying this week. Lot’s of stuff to do. Crazy computer cutting robots! 2012 PVD Chainguides for Santa Cruz V-10. More bomber. Stealth layout. 2X compatable (for TR, Butcher & Nomad).

A tale of three tires

The mountain biking season is entering it’s second phase, summer. The first rains in the late fall mark the first phase, the racing season marks the second. The Sea Otter Classic is just around the corner and the 1st National Series Race is even closer than that and the Pietermaritzburg UCI WC is this weekend. … Read more

You don’t know anything unless you’ve measured it…

You never know anything unless it’s been measured. That’s the rule any engineer lives by. Most people think of suspension systems and tuning them as some sort of voodoo or black art. The #1 problem with these folks is that they really never understood the role that springs play in the system or how springs work in a … Read more

Spring perch slippery shims.

When a spring in a shock is compressed two things happen; the spring twists and the spring cocks. When this happens, the spring needs the freedom to do this otherwise the restriction results in mechanical friction in the shock, slowing it down in an uncontrolled and unpredictable way. In motorsport, you would use a hydraulic … Read more

2012 NAHBS, Sacramento

Hey folks. Here are my pictures from the 2012 North American Handmade Bicycle Show in Sacramento California. Enjoy!  

Santa Cruz Butcher Pivot Pin Issues

***THIS ISSUE HAS BEEN RESOLVED – SEE THIS POST*** I like my Santa Cruz Butcher. It’s a fun, solid, no-frills trailbike. I got it for that reason. I didn’t want to mess with it and I wanted solid.A creak had developed in the main pivot. I hate that. I hadn’t taken it apart when I … Read more

Headspace Shims!

I just made a few of these little dandys. They are shims that are placed within the split bolt of the Ruger 77/22 to adjust the chamber headspace. A 22LR firearm should be headspaced to the absolute minimum to get the most accuracy possible from the gun. Many guns will come with far too much … Read more

Power pin!

So, I ordered up a nice little 22lr rifle to reduce my shooting costs and light enough to practice some off bench shooting. It’s a Ruger 77/22 All-Weather. It’s a gun slightly more expensive than it’s competition, but it’s got a great reputation for use, it’s made in America, and it looks awesome. Plus, it’s super light … Read more

Shimano XTR. Chainring QC Issue?

Mary was re-gearing her Nomad this morning. Putting a 26 tooth ring up front to give here knees a break climbing on the, now heavy, bike. We were checking the ring spacing when we found something off. I really hope that this is the only one that slipped through QC. #Y1LR26000, Chainring 26T-AH, FC-M980 It’s as if … Read more

Itsy bitsy spider chuck

I made a neat little spider chuck. It’s for machining the bolt of the 308AR for accuracy. A spider chuck allows me to locate the bolt exactly according to the several features that I decide are important regardless of the shape of the part. Since these parts are forged and then machined in very elaborate … Read more

New sight for the LCR!

I wasn’t happy shooting my Ruger LCR +P for a few reasons. Shooting outdoors was ok, but indoors wasn’t so hot. Josh Orlando and I were shooting at Bullseye and we both agreed that a change should be made. It was very difficult to sight in with the stock sight. I got parts ordered while doing … Read more

PVD-DMR308

The dedicated marksman rifle (DMR) – A rifle designed to fill the gap between an assault and sniper rifle. A battle rifle that can maintain accurate rapid fire at ranges up to 600 yards. I decided that it was time to invest in a nice rifle. Something that I could shoot long range (up to … Read more

Arisaka!

Early this morning, local MTB talent Ben Cruz and one of his bro’s were in the woods in Novato. They were getting a hit lined up involving a stump or tree of some sort. In the stump, they discovered a duffel bag with a few Japanese war rifles in it. Arisakas. This is a boy dream. … Read more

PVD Toe Spikes!

***Update 2017-02-23*** Time has proven that the spike configuration seen below is one of the best ways of accomplishing the goal. The importance of the fender washer stack can’t be emphasized enough. It spreads the load of the spike and reduces failure. Very long spikes are hard to justify. Most often, the result in a … Read more

NATO 7.62×51

I’ve been geeking out on guns lately. Sourcing parts to assemble a nice SR-25 Type rifle. More on that later. Here’s a nice print of a NATO 7.62×52 / Winchester .308 round.

PVD Micro-DH – PodRacerOne

This is a pretty special bike. A juvenile DH race bike for my friend Bryan Harrell’s son Jake. Jake has been racing ABA BMX (ranked 4th district CA04) for the past two seasons and is absolutely killing it. As mountain bikers and living in the best place you can for riding trail, it is only natural … Read more

RGB vs. CMYK

This is a quick little thing. Most folks have seen this before but it’s nice to remember. http://en.wikipedia.org/wiki/RGB_color_model http://en.wikipedia.org/wiki/CMYK_color_model A fun project to get working correctly in Ai. Give it a try. Obviously, I had to convert the CMYK colors to RGB for this demonstration to be seen on a light emitting source.  

The Gixxer is back!

Since getting my wrist completely shattered at RFT and not being able to do much of anything, I dropped my motorcycle off to BRG Racing to have some work finished that I had started on my motorcycle. I had the motor half apart already but there was no way that I’d be able to continue the job … Read more

A current print for an upcoming bike.

I’m getting a 29er type bike built for me this winter. All I needed to do was design it. I’m looking for it to be a nice tight fire roadie/crosser that can still ride real singletrack quickly with tires maxing out at 1.9″. Special attention is going to be put into getting the largest chainrings possible … Read more

Trigonometry

I absolutely love trigonometry. It’s how we come to understand circles and curves. I work at the Physics & Astronomy Department at San Francisco State University. Every semester a few students will express their unease, confusion, and problem doing trigonometric work. Over the years, it’s been shown that, all of them, have never been given … Read more

Very fancy dropouts for Firefly Bicycles

A long, long time ago (1998?) I designed the disc brake dropouts for Independent Fabrications. I knew the whole crew there as we had all worked at Fat City Cycles together. The reason for the design was simple, I needed a new bike and I use Shimano parts. That was the moment that Shimano had … Read more

Things going wrong, the bad way.

Things went pretty wrong at the Tara Llanes Classic. I’m bummed. Not just because of getting injured but because I really thought I had a shot at 2nd place in Cat 1, 40+. Grrr. I even had a cool bike for MegaDH. I got kicked off a big jump really bad on my warm up … Read more

MEGA DH !

This weekend is the Tara LLanes Classic. http://www.tarallanesclassic.org/. It’s what is called a Mega DH. Mega DH is essentially Super D’s wicked brother. A very long DH race with no emphasis on real climbing but a bunch of pedalling at high speeds could be involved. The key is that the course will involve true downhill trails … Read more

PodracerOne – Big Evil, Small Package

Jake Harrell is the son of my friend and business partner, Bryan. Fairfax Cyclery!!! Jake and Bryan have been racing a ton of BMX lately and Jake is proving to be a seriously fast kid. He can’t wait to get out with dad and the bros for the downhill rides. Problem: There is really nothing … Read more

BB86 is 30% stronger than BB30

Simple leverage. Didn’t anybody else do the math? BB30/PF30 has proven to be a complete mechanical failure. It was obvious from the outset and I had made good arguments against it when it was first being rolled out. The Shimano system is clearly superior but for some reason cyclists thing that everything has to be … Read more