Hoop Stress and Why Tire Pressure Should Decrease with Increased Tire Size
Hoop Stress and Why Tire Pressure Should Decrease with Increased Tire Size By Lennard Zinn This report filed June 24, 2024 We recently delivered a gravel touring bike to a customer. When he picked it up, we gave him a rundown on his bike, including maintaining his waxed chain and the pressure to pump his tires up to depending on conditions and how much weight he has in his front and rear panniers. His new bike has 700 X 45C Challenge Getaway Tubeless Ready tires. I explained that, on gravel roads with his 185 pounds and no extra weight [...]
Short Cranks or Long Cranks on a mountain bike?
When considering crank length for a mountain bike, it is important to keep in mind the type of riding that the bike will encounter as well as the rider’s morphology. The considerations for technical riding are different than for riding on smoother surfaces, and the length of the rider’s legs are also critical to crank length. “Longer” and “shorter” cranks in this article refer to longer and shorter relative to the particular rider, not necessarily to extremes on the spectrum of crank length. Here, a “longer” crank is one that is greater than 21% of the rider’s measured inner [...]
Short Cranks or Long Cranks on a road or gravel bike?
Some Pros Are Winning With Short Cranks—Shorter Than What? By Lennard Zinn It’s been in the news recently that some high-profile pro riders, like Tadej Pogačar and Tom Pidcock, as well as many top triathletes, are using 165mm cranks. This is always described as a short crank. However, whether a measurement is deemed short or long depends on its comparison with another measurement. Pogačar’s and Pidcock’s cranks are short relative to what? It seems arbitrary to consider them short simply because that is the shortest length that big component manufacturers produce. Obviously, 165mm cranks would be long relative to [...]
Bikes for small riders – Improving bike design for cyclists under 5’5″
By Lennard Zinn I built my first bike frame for my wife in 1980, three years before we got married. To calculate its dimensions, I used bike-fitting formulas in a handbook published by C.O.N.I. (Comitato Olimpico Nazionale Italiano), which I understood to be the bible of fitting of the Italian bikes that all riders lusted after in the 1970s and early 1980s. Those calculations resulted in overly long top tubes for small riders (and the opposite for tall riders like me). Watching my wife ride that too-long bike and trying to adapt it with ever-shorter stems drove my quest [...]
The Argument for Shorter Cranks on Road Bikes
The Case for Short Cranks By Lennard Zinn It’s probably clear in my previous “Why Proportional-Length Cranks?” blog post that I generally see performance benefits for tall riders with long legs in using long cranks. And by long, I mean longer than the standard 170-175mm (or even 165-180mm) offerings from the big component brands. In fact, I have found that riders will generally climb best (and often feel best) on cranks that are in the range of 20-21.6% of their inner leg length. That said, there are some applications that offer clear performance reasons for long-legged riders to use [...]
5 Benefits of Electric Bikes
At Zinn Cycles, we believe in keeping up with every aspect of the cycling world ㅡ and that includes electric bikes. Ever since Lennard Zinn, our founder, was limited to short, slow rides by his heart problems, he’s been searching for a way to get back on the horse… uh, bike. Electric bikes have come a long way from those bulky roadside rentals; they now have a lot more benefits to offer. If you want to learn about the benefits of electric bikes, and how Zinn Cycles is taking them to the next level, read this blog post. 1. [...]
E-Bikes for small riders
By Lennard Zinn In the new world of e-bikes, cyclists under 5'5" are stuck with an array of clunky and heavy bikes that feel like some rendition of our grandmothers grocery getter. If you have been a cyclist and are used to a quality feeling bike, it's hard to ride something that weighs 60lbs and feels like a heavy beach cruiser. We have been building titanium custom electric bikes for small adults for years now and really understand what it takes to make a lightweight and performance oriented ebike that is comfortable and fun to ride. Many of the [...]
Testimonial: Zinn Custom Titanium Electric Gravel bike
A happy customer sent us an email reviewing his new Custom e-bike. We worked with this customer who had some body mechanic issues to build a great custom bike. He did the Gold Medal Bike fit that includes an initial fit with Lennard Zinn followed by a full body analysis and 3D retul fit with Larry Meyer at BUILD sports performance lab in Louisville. Zinn Custom E-bike review Dear Lennard, This week the weather turned. It’s 75 degrees here and I’ve just returned from an outdoor ride on the custom titanium gravel e-bike. And what a ride. I [...]
Diagnose a creaky sound on your bicycle
By Lennard Zinn Although sometimes difficult to diagnose, a creaking sound coming from your bike is always caused by movement between two parts that are supposed to be tight against each other. Could that annoying sound be one of the rotors rubbing? .... It used to be that a cause of creaking was often the interface between the quick-release skewer and the fork. With through axles, that’s less likely. It’s still worth first checking that the through axles are tight. If they are, remove the through axles and grease their threads and under their heads and tighten them up [...]
Bicycle Crank Length
Being tall, and thus being accustomed to always getting every piece of clothing in the longest length available, when I built up my first racing bike from scratch in the 1970s, I got the longest bike crank arm length available, which was 180mm. I was successful on that bike and could climb with almost anybody, despite being so big. When I got my first Italian bike, that beautiful Masi had 177.5mm Campagnolo cranks, and I went to considerable additional expense to replace them with 180mm ones. The day after making that little 2.5mm increase in bicycle crank length, I dropped [...]
Custom Travel Bike with Internal Brake Hose
This Custom Zinn Titanium Travel bike was built with Z-couplers for an extremely clean look. The Z-couplers virtually disappear into the frame. We also use a coupler in the hydraulic brake hose to allow for internally routed brake hoses. Watch the video to see how it all works.
Taking care of your new bike – regular maintenance schedule
Congratulations on your new bike. We hope you get many years of riding on this bike. Your Zinn, Clydesdale, or Tui bike has been assembled with care by one of our seasoned professional bike mechanics and checked off by our team. We ensure all components are installed properly, shifting is tuned, brakes are bedded in, and brake calipers are centered and adjusted. We warranty the assembly of your bike for 3-months from the date of delivery. If you find any issues with the assembly of the bike, please submit a service request form here and we will determine if [...]
Designing a super strong carbon fork
After three years of extensive testing, redesign, and further refinement, we at Zinn Cycles and Clydesdale Bicycles are proud to announce our revolutionary Zinn Duro fork. We have long awaited a carbon fork that is tough enough for the abuse that gravel cyclists, bikepackers and big and tall cyclists dish out. Our vision included a carbon fiber bike fork made to match our super-strong, bike frames in durability and fit. Having a fork that can perfectly fit any size bike from small to 4XL is a huge deal in the bike industry, for tall riders and average sized riders [...]
Why titanium is the best material for gravel bikes
By Lennard Zinn Do you know someone who has broken a bike frame? Most likely it was made from carbon fiber or aluminum. that had to hurt Over the past 10 years, big bike brands have have been pushing carbon fiber bikes on the world. Is this because the material is superior to all others or does it have more to do with profits? When asking executives at many large brands, the answer is increasingly clear. Carbon fiber bike frames have incredible profit margins. To be clear, I am not anti-carbon. I actually believe it has some [...]
Fixing Flats: How to Fix a Tubeless Bike Tire
Wondering how to patch a tubeless tire? If you flat a tubeless tire while on a ride, you have three options for dealing with it so that you can keep riding: 1) Install an inner tube; 2) Inject pressurized sealant into it; and 3) Plug it. 1. Install an Inner Tube You should always carry a spare tube, tire levers, and a mini pump or a CO2 cartridge inflator with you when riding. In the event of a giant hole, installing a tube is the only way to keep riding, with the addition of a tire boot (an energy [...]
Cost savings with waxed chains
By Lennard Zinn As I explained in a prior blog post, immersive chain waxing can save you a lot of money vs. using oily drip lubes or the original factory lube and anything applied over it. The lower chart here shows how huge those dollar savings can be. If you have a modern aero road or gravel bike with fully internal cables from the stem and bar through the frame, it makes no sense biomechanically or financially NOT to ride on waxed chains. Continuing on the aerodynamic vs. friction savings, it doesn’t even make sense to invest in aero [...]
Fall Colors Gravel Ride Report
By Lennard Zinn Nick and I and Cleo, the Zinn Cycles shop dog, woke up on Saturday, October 7, 2023, to a cloudless and rapidly warming Colorado bluebird day at our campsite near the Little Book Cliffs. The Grand Mesa, the largest flat top mountain in the world, was bedecked that day with giant golden splotches of aspen trees in full fall foliage. It beckoned to us to cross the Colorado River and Interstate 70 and head south toward it. We did exactly that, on an idyllic gravel road. At Roan Creek Cyclery, across the street from the Reckless [...]
Immersion Chain Waxing
By Lennard Zinn When I was racing in the early 1980s, new chains were $4 retail. Now, a good-quality chain for an 11- or 12-speed drivetrain is at least tenfold (often even twenty- or thirty-fold) as expensive. And if you keep riding with a worn chain, you will have to also replace your cassette, which is far more costly than a chain—as much as $600. Getting more life out of your chain will save you money, and it would be a nice bonus if you also could ride faster with the same energy expenditure or use less energy to [...]
