Mary Pralinsky wanted a beater bike to take to the jumps and to the pump tracks. She wanted something cheap and unbreakable. Nothing can touch a Specialized P3 when it comes to that. The bike is heavy and indestructable. She found someone selling a used one with 90% of the parts for $200 and picked … Read more
So…. My friend Matt gave me a call. He had purchased a basket case VW Super Beetle project car. The car had had a lot of work done on it but wasn’t completed and it needed an engine. Matt had a line on a Porsche 914 engine that would drop right in. He purchased both … Read more
A Super D bike is a very special kind of bike. 90% DH Trail with 10% Climbing. Super high speeds on smooth to aggressive surfaces. You need a light bike but something that works right when treated rough. 160mm frames tend to work especially well in this situation if set up well for pedaling and … Read more
Named for NASA Project Gemini, since it’s the bike after Mercury. This is the first of a pair of bikes, one mountain and one road. They will reflect a snapshot in both disciplines of my bike design techinque. They will share several design cues. They will proabably be painted the same color. Since these will … Read more
This past week has been all about Mary. Two of them in fact. Mary Pralinsky and Mary Moncorgé. Mary Pralinsky is a friend of mine racing DH as an expert this season. Mary Moncorgé is racing PRO in GRT and nationals with Santa Cruz Alliance. Both needed fully prepped race bikes for the season. They were nice enough to come to … Read more
My SC Butcher bike has some serious drive train issues that make it less than fun to be on. It functions, but it’s so floppy and loose that it ends up being something that I think a lot about on a ride. That sucks. Gonna fix that. I don’t want to strip the bike down … Read more
Hey folks, Juliana Gallin of How-to Night SF was nice enough to invite me to lecture on how folks can build their own bicycle frames at home. Of course! It’s easy. How-To Night at Bazaar Cafe Wednesday March 9, 2011 • 7 pm • How to Build a Bike From Scratch Bazaar Café 5927 California Street, between 21st & … Read more
Inspired by products designed and made by Magic Motorcycle in the early nineties. Some wild stuff. Probably not the best, but intriguing to say the least. Especially if you are a machinist type like me. So, 2×10 has taken hold in mountain biking. It has a place but certainly 3×10 does as well. Shimano has … Read more
The radar mount was installed today. I mentioned it in an earlier post. Very cool. It took some planning, lots of rope and safety harnesses but it was installed without issue. A 40 foot drop on one side and an 18 foot drop on the other. No screwing around on this job site.
I’ve been quite busy lately… The modular throttle project is just about done. Final testing takes place this weekend but this revision is assumed to be the last. Prototyping has been a long process for this. The engineering was quite a learning experience for such a simple little part. A 60 degree variable rate cam that … Read more
This is a neat project from work. It’s a straddle mount that will sit on top of a wall above the water treatment facility on Ocean Beach. It will support a 9′ rotating radar boom against anything the Pacific Ocean can throw at it. 0.375″ stainless steel, plasma cut and welded together.
These are the all new PVD headtubes for the 2011 Gemini bikes. A pair of bikes following Mercury. A road and a mountain. They should be completed prior to NAHBS for all to see. Show bikes made to be ridden hard, put away wet and taken out again and again. Top bearing is Cane Creek … Read more
Named for the NASA Mercury space program. Seriously rad! The 2011 PVD Mercury Trailbike. Tapered head tube, 2×10 designed, DMFD, ISCG05 w/slider, BB92, with clearance for 3.0″ tires. Like all PVD Trailbikes, this bike is designed specifically to completely dominate Marin California singletrack. The time tested and challenged design sets the standard for high speed … Read more
2008 GSX-R750 Tie Down Tabs for rear end. mounts under the passenger peg bracket. A nice feature for transporting or working on the bike.
Math and numbers rule! You can learn a lot from them. This weekend I put my nose to the grindstone and measured the weights for my bike and weight distribution. Bike weight (full of fuel) – 444.5 lbs. Ride weight (no gear) – 203 lbs. Gear weight – 18 lbs. Weight distribution – 49F/51R (note … Read more
Here’s a fun little project. Motorcycles have engines. We all know that. What few truely understand is that we use our throttles and gearing to access and make use of those engines. Asside from gearing issues that I will cover later, throttles typically need modification so that we can get all that power we have … Read more
Here’s the new bike. Soon you’ll be seeing a lot more tuning projects based on this. I’m super stoked.
It’s not easy making things and bringing them into this world. It takes a lot of time, energy, money, devotion, and lonely days in the shop. I’ve got so many projects started right now and many more that I’d love to start. Why not? Life. Lately I’ve been really putting a lot of energy into … Read more
It’s been a few months since I’ve build a bike frame. I needed to update my geared trail bike with a few new updates in my design but one issue was lagging. 1.125″ straight steerers are effectively dead. It’s all tapered now. The light carbon forked folks like it. The burly slopestylists like it. Everyone … Read more
As the proud new owner of a 2011 Fox Vanilla 36 160 fork, I finally got around to give it the TLC that it deserved. I had already swapped the stock ‘blue’ spring (039-05-102, 45 lb/in) for a stiffer ‘green’ spring (039-05-103, 50 lb/in). That’s a pretty simple task and takes about 5 minutes. It … Read more
This past April I moved to the Bernal Heights neighborhood in San Francisco. Quite a culture shock for me to be sure. Fairfax is a very differnt place. This part of SF is about 15 minutes away from one of the major casual DH/Jump locations in the bay area, Pacifica. An odd thing about Pacifica, … Read more
Riding at Northstar this past weekend. My trusty steed the Intense M6 finally had an issue. 2.5 seasons of riding and the pivot link pertch broke off. I was able to get a good day of riding in on Friday, but at the bottom of the last run of the day the snap cracks and … Read more
You don’t know anything unless you’ve measured it. A very wise tuner passed that statemet down to me. I learned a lot from him. Dan Kyle. Look him up. People get pretty spooked about suspension. They get lost. They get confused. I used to. Then I bought a spring scale and everything made much more … Read more
Lately, I’ve been trying to recruit some folks from the city to go ride mountain bikes. Not fire road burns, but honest singletrack trail mountain biking. It’s an amazingly hard thing to do. I ask, “Would you like to go ride mountain bikes with me?” They say, “Maybe, I usually ride over the bridge to … Read more
On Sunday I rode up to West Point Inn for the pancake breakfast. I saw plenty of friends there that had the same idea. Sadly they were on cross bikes while I was on the mountain bike intent on trail riding. The ride – Tenderfoot: Cypress: 777: Gravity Car: Railroad Grade: West Point Inn: Railroad … Read more
Sorry, I’m out of the office right now. I’m busy elsewhere doing important things…
I ride my mountain bike on single track trails. These trails, I keep assuming, are my friends. I spend time with them. I love them. I fix them when they are hurt. I work hard to keep a quality relationship with them. I forget to think about what the trail thinks about me. What does the … Read more
Anybody that knows me will already know that I am the first to question a person’s equipment choice on a bike ride. I question actively, vocally, and (in my mind) friendly way. One major tenant of mine is that cyclocross bikes are stupid bikes. They excel in only two situations; cyclocross races and mixed terrain … Read more
#1 on my list is, of course, England. Top reason: BSC (60°) thread, special case, 13/32″ x 26 tpi. Let’s just call this the Sturmey-Archer thread from hell. It’s doesn’t conform to SAE, ISO, JIS, DIN or any other modern standard. It’s not even Whitworth (55°), which you might imagine. It’s a special case, used only by … Read more
What is up with Brooks saddles? 1. Heavy as hell – The lightest saddle that they make is the B15 Swallow Ti. 370 grams. Mind you that is the lightest one. Most of their line weighs in at 500 grams or more. Much more if it’s got springs on it. 2. Lame looks – Honestly … Read more