Category Archives: Exercise

SRAM Bike Brake Stiff Lever

Exercise
by Mike Clements

Update: 1 year later

The levers got slow again. Not as stiff as before, just slow to return. On disassembly, the problem wasn’t the pistons, but the seals, which had swelled. Maybe because I put a drop of oil on them when I reassembled them, and oil can have seal swelling additives.

Anyway, all I needed was new seals. But new seals alone are not available, as far as I can tell. You have to buy an entire brake lever rebuild kit! However, I did find replacement pistons that come with new seals, and the pistons are machined aluminum, and they only cost $5-$10 each. Better than OEM quality, and perfect fit.

—

The brake levers on my MTB have been gradually getting stiffer to operate, more friction in the brake pull with a weaker return upon release. I bought this bike in late 2014 and have bled the brakes and replaced the pads. The lever stiffness has been gradually increasing. On my most recent ride on Tiger Mtn, the brakes were dragging pretty hard because the levers wouldn’t return. This was an incredible PITA on the steep uphills, and risks overheating the brake pads & rotors.

At Tiger summit, one of the other riders mentioned this was a known problem with SRAM hydraulic brake levers. When I got home I checked it out and found that was indeed true. Some people had returned their levers to have SRAM replace under warranty. But they said it was a PITA and took a long time because SRAM support dragged their heels not wanting to admit there was a problem. So I figured it was worth at least trying to fix it myself.

There are several YouTube videos about this. Here is one I found useful: https://www.youtube.com/watch?v=Ex882BIH-Fo

Here’s a summary of the problem and fix. Each brake lever has a small master cylinder inside, a piston with rubber seals. The piston is made of plastic and the cylinder is metal. Inside the master cylinder there is also a spring that pushes back against the piston to help it return to the neutral position. When the entire assembly gets warm/hot, the piston expands more than the cylinder, scuffing against the inside of the cylinder, increasing friction and getting stuck. It gets stuck so hard that the spring can’t push it back.

The solution is to remove the master cylinder piston and use fine (600#) emery paper to scrub off edge material (gently, smoothly, evenly), making it slightly smaller in diameter. To do this you must remove the brake lever from the hose, drain the brake fluid from the lever, disassemble the lever, remove the piston and its rubber seals, sand it down until it freely slides back & forth in the cylinder, clean everything up, reassemble it, then re-bleed the brakes. The procedure is tedious manipulating some tiny parts, and requires an experienced touch sanding down the pistons. But it doesn’t require any special tools, just the usual stuff: torx wrenches, brake bleed syringes, fresh DOT 4 or 5.1 fluid, etc.

The procedure was successful; my brakes are like new again. This took me almost all day, but I hadn’t done it before. I could do it again in less than half a day.

The problem is definitely not about the piston’s rubber seals. I removed those before sanding it, and the piston was super-tight in the cylinder even with the rubber seals removed and the cylinder cleaned. I sanded the piston until it was loose in the cylinder, easily sliding back & forth from gravity just tilting the assembly up and down.

The piston’s rubber seals are tight and one-directionally facing. Remove with care, ensuring you don’t scratch or score them, and ensure they’re facing the right direction when you reinstall. Before reassembling, make sure everything is scrupulously clean. You don’t want sanding dust from the piston or other crud inside your brakes!

I can’t figure out how or why this problem took 4-5 years to manifest. The piston was not deformed in any obviously visible way. Why didn’t this happen during the first year of ownership?

I Broke My Arm!

Exercise
by Mike Clements

Riding Tiger Mtn on Sat 5/12 with a friend, a wet slimy tree root suddenly torqued my front wheel around and I hit the ground hard, banged up but all body parts still firmly attached. I continued riding, but every bump triggered sharp pain in my left shoulder, so we got off the trail and rode out along the (less bumpy) gravel fire road. That meant climbing back up to the summit again before we could go back down. The good news: we got a tough cardio workout with 4,000′ of climbing in 15 miles. The bad news: got some x-rays on Mon 5/14 and found out my left humerus is fractured. I can still ride but will stick to the machines in the gym for a few weeks.

The break is a crack at the upper end of the humerus where the ball-shaped top end tapers to the straight part of the bone. The doc says it will probably heal on its own, but there’s some chance the shoulder muscles might pull it out of alignment, in which case it will require surgery to realign the bone.

I’m getting another x-ray soon to see which way this is going.

4 years later… I don’t know why I didn’t put up the pictures. They’re quite interesting, showing how fast bones can knit and heal. Bone injuries can heal faster than ligaments. In 13 days the bone had closed and knitted the crack, though it took several more weeks to fully heal.

Day 2 – cracked

Day 13 – crack is closed and knitted!

Seattle Lime Bike: Test Ride

Exercise, Travel
by Mike Clements

Seeing their bikes all over the place got me curious about Seattle’s bike services, Spin and Lime bike. I installed both apps on my phone and they both worked just fine, popping up a map showing where the bikes are. In both apps, the first ride is free. Neither app asked me for credit card info, though presumably they would later if I continued riding. They both have plenty of bikes downtown, though Lime seems to have more bikes in outer areas like Magnolia and Ballard.

Walking home from the Magnolia center district today, Lime said there was a bike nearby. I followed the map a couple of blocks and the bike was exactly where the app said it would be. I used the app to scan the QR code, a few seconds later it unlocked. The bike was mine!

I rode it a few blocks home. My impressions:

  • It’s a tank – weighs 49 lbs!
  • Has a basket in front, whose bottom is a solar cell.
  • The front wheel has a built-in generator that powers a front & rear light that are always on when the wheels spin.
  • It has fenders and a full chain guard.
  • It has an 8-speed Shimano Nexus internally geared hub. It works smoothly, though it was slightly out of adjustment due to a bit of cable stretch, skipping some gears (like 3rd). A couple of cable adjuster twists fixed that, then it shifted perfectly.
  • It’s geared low, which is a nice touch you really want around hilly Seattle, especially for this 49 lb. tank of a bike.
  • The brakes are Shimano drums.
  • The tires are not pneumatic and can’t flat. But they’re not rock-hard either. Seem to be foam-filled.
  • The seat is easily adjustable with a hand quick release. But it doesn’t go quite high enough for my average length legs (32″ inseam).

Overall, it’s a comfy bike to ride around town. At $1 per 30 mins it’s cheap too, with bulk monthly rates for unlimited rides.

Next, I want to try a Spin bike.

Sturmey Archer S2 Hub

Exercise
by Mike Clements

A few years ago I resurrected my brother’s old bike into a commuter. It’s still running great and I enjoy riding this unique old bike to work. It weighs 24 lbs, perhaps 1-2 lbs lighter than what it weighed new from Trek back in the 1980s when it was made, due to removing the derailleurs, rear cog, now with single front chainring, etc. I’ve put a couple thousand miles on this bike since resurrecting it. I wish the S2 hub ratios were further apart so the low was lower, but it’s proven solid and reliable.

Nordic Track 2450 Treadmill

Exercise, Health
by Mike Clements

We recently got a Nordic Track 2450 treadmill to help us stay fit through the long, dark, cold, wet Seattle winters. I have been running on the commercial treadmills (Precor 932i) at the gym for the past few years, so that’s my point of comparison.

Good Stuff

We ordered it online because none of the local shops could come close to the price. It has a good warranty, 30 day no hassle return, shipping delivered to the room of our choice (which is important as it weighs over 300 lbs.), shipped promptly and arrived in perfect condition. Unpacking and assembly took nearly 2 hours but was simple.

The Nordic Track feels as solid and smooth as the more expensive Precor, has a more powerful motor, a slightly bigger running deck (60″ x 22″), elevation from -3* to +15*, adjustable deck firmness, and far more features. The iFit capabilities are super-cool and work well, even supporting multiple users under the same account.

It has 3 fans to blow air on you, cooling and reducing the amount of raw sweat dripping off your body onto the machine. The fans work well enough and aren’t too loud. They can be set manually or automatically, where they blow harder when you run faster. I find the auto mode doesn’t blow hard enough – during a tough workout when my heart rate is the in 160-170 range, I need those fans on full bore.

It includes a wireless heart rate chest strap that works well. The system is polar compatible. It also has handles you can grab that read your heart rate. When first grabbing the handles, I get crazy readings, often half or twice my actual heart rate, for the first minute or so, before it stabilizes on the correct reading. The chest strap doesn’t do this – it reads accurately from the start.

If none of the 40 built-in workouts float your boat, you can create your own – any number of your own – customizing elevation, speed, etc. You can also schedule them, set goals and track progress toward goals, if you want. However, all this requires iFit.

iFit adds a lot of capability and fun to this treadmill. You can download any number of workouts of all types and difficulty levels, many with Google street view maps across the world, including some exotic locations, and you can design your own too. When you run these, you see the actual street view and the elevation changes to match the terrain. It moves along slowly, more like a slide show than a video, but it’s still neat. I was a bit concerned about iFit since my research showed it had a rocky launch with lots of bugs a couple of years ago. They’ve fixed most of that, it works pretty well but still has the occasional crash – more on that below.

The control console response is not instantaneous, but reasonably quick, the touch screen responds to light touch and doesn’t miss gestures like swipes. The screens are well organized intuitively, easy to navigate.

Bad Stuff

iFit is marked as optional, yet it’s required to get the most of this machine. And it costs $100 / year. Without iFit, you can run the machine manually and it has 40 different built-in workouts. But I couldn’t find the simple workout I wanted: intervals with 2 minutes slow and 1 minute fast. I call this a simple 2-1 interval. In fact, among all 40 workouts there were no simple intervals at all! Not 1-1, 2-1, 3-1 or anything close to that. So the “40 built-in workouts” is just a marketing ploy – it’s true, but misleading and not useful. As mentioned above, you can build your own workouts, but only with iFit.

The console runs Android and I can tell from the boot screen it’s some ancient 2.X version. It has a built-in browser that is so terrible as to be unusable. On some sites (including, inexplicably, iFit itself), no text appears, making it unusable. Perhaps it’s a character set or font issue? I don’t know, but you might as well disable the browser in the machine settings because it’s totally unusable. Other than this, the console works just fine.

The heart rate monitor bar is effectively unusable. It’s wildly inaccurate (at least for me) and using it can crash the console under certain conditions (see below). If you want heart rate, use the wireless chest strap – it’s more accurate and it doesn’t crash the console.

The most annoying problem with the 2450 is the console occasionally crashes, sometimes while in the middle of a workout. Here are some conditions that trigger this:

  • Using the heart rate monitor bar while running a Geo workout in street view. This will usually crash the console, though it doesn’t happen immediately.
    • Workaround: don’t do this. If you want heart rate, use the wireless chest strap – it’s more accurate anyway. Or, if you’re running a Geo workout, switch to map or satellite view before using the heart rate monitor bar.
  • If you have an un-named workout in your history, the 2450 console will crash when you touch the yellow “log-history” button.
    • Workaround: use the iFit website to rename or remove the offending workout.

Conclusion

I think the 2450 is a good value. It has some quirks but they have workarounds. I was pleasantly surprised to find it as solid, smooth and quiet as more expensive commercial treadmills, and total cost shipped to my door was about $2,100. The iFit subscription is required for all practical purposes, though at $100 / year, supporting up to 4 individuals, each with their own history, workouts, etc. the cost of an iFit subscription is small in comparison.