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Rock Armoring at Oakland’s Joaquin Miller Park

jasonvh — Sun, 24 Apr 2011 20:39:45 +0000

Every time we ride the bike friendly trails in Oakland’s Joaquin Miller Park we would comment on a particularly bad section of trail. It was essentially a mud bog that stayed wet all winter, even when every other part of the trail was dry. It was so bad that a go-around route had been formed by hikers and cyclists that had no desire to play in a swamp. It turns out that many other local mountain bikers felt the same way, so when we teamed up with the Bicycle Trails Council of the East Bay for a trail repair day, there was an excellent turn out.

The swampy section of trail: before. (shot on an iPhone)

The BTCEB did a great job rallying volunteers, as well as sourcing the materials we would use to harden the tread. The morning of the trail day, Daniel and I headed down to get a plan into place. Our first item of business: pull all the mucky organic material off the trail, as well as the sticks and logs that lined the mess. Most of the water that existed in the “before” image was gone, and while the surface was still mushy and damp, we were able to see the two well defined ruts running down the trail. The ruts ended up being somewhat useful, as we used one of the ruts as a shoulder to pack our rock into.

When our trail crews arrived on the scene, we went over our game plan for the morning and split up into several different groups. Group one would hike up to the road and transport the chunks of concrete down to the site. Group two worked to clear all the branches and organic matter away and prep the work site. Since the section was completely straight, we laid out a few branches to visualize the entrance line into the section in place of pin flags. (we didn’t have any) Instead of having a completely straight section, our plan was to break it up a bit by placing corral rocks and add some curves.

We also cut a bit more backslope into the uphill side of the tread to minimize erosion and guide water down and over our trail. (We cut our backslope at a standard 45º angle.)

Mud and muck now excavated, we began laying in our anchor stones.

Most of the trail has good flow, and my personal goal is to contribute to making a lot more of this good stuff happen throughout the entire system. (see the previous Flow Country article) To keep riders from straight lining the section, we added a stack of rocks to act as a corral and direct riders into the berm. More bermed turns= more sweetness.

Once we had materials stacked at various points at our site and had excavated a channel to place our stones, the group took a break for a quick rock armoring demo from yours truly. Since we had a lot of cool broken up pieces of concrete, we would be able to do a mix of flagstone paving and stone pitching. We broke up the section into a number of different cells, with keystones set up every 6 feet or so. Since we had a limited amount of concrete, we placed the rock to form a tread 12-18 inches wide, with the anchor stones a bit wider.

Rock armoring in progress

We weren’t sure what was actually causing the water to seep into the trail, so we laid down a bed of aggregate underneath our flagstones, and added drains at several points. After we placed our stones we packed them tightly with the small rocks to make the surface as solid as possible. Taking it a step further, we smashed some rock up to pack it all in.

Flagstone paving in progress

We placed our broken up sections of former sidewalk smooth side down, so that the surface facing up was rough and looked more natural.

Inga poses with her completed section of rock

We didn’t have enough of the large pieces of concrete paving, we did some sections with a slightly different approach, pitching a number of the stones on their side. (much like a bookshelf-see the piece Inga is holding in the photo above) Since most of the stone is buried and packed as tightly as we could make it, the idea is that it will remain stable, even with the additional moisture from an underground spring.

Almost there- our trail work in progress.

To keep the entire section from being a complete straight shot and to keep trail users on the hardeneding tread, we placed rocks along the side of the trail at strategic points. The trick was to maintain the personality of the rest of the trail, which has some pretty solid flow.

We also tamped aggregate into the tread before our rock armor section.

We only had enough rock to focus on the wettest part of the trail, but we had enough small crushed rock that we were able to pound some into the tread, creating a transition point from straight dirt to the rocked section.

Talking about flow.

Test riding the finished work.

The best part of trail work is riding it afterwords. This section of trail which had turned into a hike a bike around a swamp, was now totally solid and ridable. We finished things off by decommissioning our trail builder line in from the car, as well as the go-around that had been formed on the uphill slope. Note the randomly placed rocks in the above photo and the vertical deadfall. We also disguised our trail work by spreading dry leaves around the side of the trail.

A stoked trail runner came through just as we were finishing up.

Trail Crew group shot with the completed trail work

Close up of the trail tread, "after."

Compare it to the before- it doesn't even look like the same trail.

Reader Question: Fixing RP23 Bottom-out issues

jasonvh — Wed, 12 Jan 2011 18:50:20 +0000

Élio from Portugal writes:

I own a Trek Remedy 08 as you, I found that the only bad point is the rear suspension and I’m thinking on buying the new monarch plus rc3, I like to ride hard and last year I went to the mega avalanche and I had to put more air in the chamber for not bottoming out my suspension constantly, should I buy the normal version without the large volume chamber to get a more solid rear, or the other way, did notice a lack of sensitiveness on the rear wheel?

I hear you Élio. The rear shock as it came on my Remedy kind of sucked. I was having issues with it all the time- when set up with proper sag, the bike would corner and handle great. That is, until I took a really hard hit, and the suspension would bottom out. It turns out this can all be attributed to the high volume air canister these bikes were spec’d with. The stock XV (XV stands for extra volume) offers a larger air capacity which was chosen to give this bike more of a linear rate to the air spring, and for typical riders supposedly works well. Apparently a lot of people have trouble getting full travel out of their shock or something. That has never been an issue for me, in fact, I consistently have the opposite problem. The same XV can issue was something I also experienced with my Intense Tracer VP- the exact same issues. I could set the bike up to corner well, or to handle harder hits. The problem with adding air is that small bump capacity starts to suck.

Swapping the stock high volume air can on my RP23 for a standard can made a huge difference in my ride.

The current iteration of the popular Fox RP23 rear shock appears to be their highest performer to date. The biggest upgrade over previous models is the addition of the boost valve, which can be adjusted to add damping to the beginning or end of the stroke. I’ve heard mixed feed back on how it works, but theoretically this would be a big upgrade for aggressive trail riders. Especially if like me, you have had issues with bottoming out your rear suspension when set up at the proper sag. Having this option on my 2008 Remedy would have been a nice upgrade, especially since the bike came stock with an XV air can on the shock. I’ve heard great things about the Monarch as well, though I would definitely recommend the standard air can.

While you could certainly try purchasing a different shock, I ended up giving a call to Push Industries and spoke with Darren there. His recommendation was to swap out the High volume XV air can for a standard volume air sleeve. The smaller air can runs $50, which is way cheaper than a new shock, so trying this option was a no-brainer.

Changing out the larger volume can for the standard made a big difference for me. The bike worked quite a bit better for my riding style. It still has the cornering performance, but my bottom out issues were significantly reduced. (There is a reason you won’t see the XV can on Slopestyle or Dual Slalom bikes.)

There is a popular thread on MTBR that addresses this issue as well- it isn’t limited to the Remedy, as I found with my Tracer. Lots of other riders have had this issue as well. Click here to check out the thread. The approach these guys have been taking has been to shim the XV air can, which effectively does the same thing- it reduces the air volume. They both have the same results- a shock rate that ramps up at the end of the stoke, reducing bottom out. There is also another great thread here, that Darren at Push chimes in on, with a cool graph demonstrating air spring curve rates.

There are better options than both of these those. Push offers a tune that can set up your RP23 exactly the way you want it to. Their big air tune offers a conical bumper system that aids in bottom out control. The big hit tune runs $179. I have a feeling they’d tell you to change the air can out as well. You definitely have a few options with your current shock, which is a solid performer, it just needs to be set up the right way for your riding style. You can always give the guys at Push a call too. They have heaps of suspension knowledge, and are super helpful.

Hope that helps!

Swapping out the air can/ Float Air Sleeve Service

Swapping out the air can and/or installing new seals on the RP23 is pretty easy.

remove the lower mounting bolt

The first thing I did was to remove the lower mounting bolt and depressurize the air can. Make sure to get ALL the air out.

I left the shock attached since I don't have a vice, much less a vice with soft jaws in my living room.

Placing some padding beneath the shock, I unthreaded the air can. Again, make sure all the air is removed. If you are replacing seals to fix a “stuck down” Float or DHX Air, there will be a bit of air trapped in there, and there will be a solid POP when it comes off. I left my shock bolted in for leverage, since I don’t have a vice at home.

Pulling it all apart

At this point I removed the shock completely and slide the air canister off carefully.

Prepping seals for installation

At this point I cleaned everything and prepped the new seals by covering them with Float Fluid. Using my dental pick I carefully removed the old seals and replaced them with the new ones.

Completed shock service

Then it was just a matter of carefully reassembling everything, using plenty of fluid on the seals. If you are mechanically inclined and do all your own maintenance, it’s too hard to do; in fact, I had to deal with a stuck down shock in Moab once. Fortunately the local shop had a seal kit and I was able to replace the seals in the parking lot. It is a lot easier when you aren’t doing this in a windy parking lot.

Doing a DHX Air seal replacement in the field. Moab, Utah.

Low budget suspension pivot maintenance: Trek Remedy

jasonvh — Thu, 23 Dec 2010 22:34:09 +0000

Riding wet and muddy trails isn’t the best idea for both trail conditions as well as our gear. Trails can develop ruts and problem areas on the trail can become even worse. It is hard on our gear as well- mud seems to have a way of getting into every nook and cranny of our bikes. Keeping our high performance rides at a level of high performance after riding in crappy riding conditions can be a lot of work. Some of the obvious maintenance would be cleaning and lubing derailleur cables, as well as the chain, derailleurs and cassette. Eventually though, our bikes will need a lot more.

My Trek Remedy after a hearty romp in the wet stuff.

That would be it if we were still riding basic hardtail frames. Today’s bikes have quite a few more moving parts. In addition to cleaning and lubing the drivetrain, we have front and rear suspension, as well as moving parts in our adjustable height seatposts. After a long and wet spring last year in the northwest, my Trek Remedy weren’t working so hot. At one point my headset had actually frozen up. Wrenching it side to side, I was able to work it to the point where it only had a notched feeling. Not only that, my suspension pivots creaked with every pedal stroke. Later I start having issues with my fork when oil started seeping from the seals. Ugh.

I don’t really have a dedicated shop space to work on my bikes these days, (so I have been servicing my bike a bit less than normal) but it is clear it was time to give the Remedy a bit of love.

Mud in the headset actually locked up the bearings.

Although my bike uses cartridge bearings with seals designed to resist the elements, after a hard season of wet riding, enough mud had made its way in to freeze everything. One option for a fix would be to replace all the bearings in our bike. However, after a single season of riding, the bearings aren’t always used up. If you don’t work in a bike shop or have a budget for new parts, these supposedly “unserviceable” bearings can often be serviced with just a bit of elbow grease.

Pulling the cranks

Servicing the main suspension pivots

When it came time to tackle was the creak in the bottom bracket area/ main pivot I started by pulling the BB and cranks, greased everything and reassembled it. After the next ride, the creak remained, so it was time to go deeper. However, in order to get to the main pivot, the cranks, chain guide and bottom bracket needed to be removed. At this time, it’s always good to clean everything as you go.

Pulling the main pivot bolt

After removing the main pivot, the sealed bearing were exposed. To remove the cover, I carefully used a dental pick to pry it off and expose the ball bearings inside.

The exposed ball bearings

Once the ball bearings are exposed, it is just a matter of cleaning off all the gunk and contaminants.

Cleaning out the gunk with some solvent

This is exactly what WD-40 is good for. After spraying everything down and cleaning out all traces of mud and dirt, it’s time to repack it all with copious amounts of grease.

Repacking the bearings with grease.

After filling the bearing with fresh grease, press the bearing cap back on, and put everything back together. I applied Blue 243 loc-tite on the pivot bolt threads and tighten the bolts to the correct torque. I also made sure to apply grease to the pivots- this is a key step to making that annoying creak-usually caused by movement of metal on metal- go away..

Then put it all back together.

I redid the procedure with the other bearings, including the headset. Then clean (if you haven’t already) and reassemble everything and you are good to go. I checked the bearing play by unbolting one side of the rear shock and testing the suspension movements by rotating the rear swing arm up and down. Everything felt smooth, and once I reassembled the bike and did a test ride, it was clear the creaking was gone. Step one of winter service complete.

How to do No-foot Cans with Transition Bikes

jasonvh — Mon, 26 Oct 2009 16:54:11 +0000

When I saw this clip, I had to repost it, as I have wanted to learn this trick for a long time- Transition Bike factory rider Mike Metzger breaks down the no footed can-can trick step by step, in possibly the best way I’ve seen it explained to date.

Now I just have to get a nice step up jump built that will facilitate learning new tricks…