Monday, June 30, 2014

Clyde Forks mine

Just west of the abandoned K&P rail line near Clyde Forks, in Lavant Township, is an abandoned mine site with workings in remarkably good condition. Getting there is fairly straightforward and involves a bit of GPS work to find the precise location in the bush. However, I will not provide details here since it's not exactly safe to rummage around old mine sites without taking proper precautions. Experienced mine hunters will know what I mean and will also know how to find this particular mine without problem.

The Clyde Forks Deposit was first staked by "T. Caldwell" in 1918-1919. I'm guessing this was Thomas Boyd Caldwell (who went by "Boyd"). His father (also Boyd Caldwell, just to keep things confusing) had, in January 1880, opened what became known as the Wilbur mine on the K&P south of Clyde Forks. As a widely invested entrepreneur and member of federal parliament, T. Boyd himself most likely remained in Ottawa or his Lanark riding sipping Scotch, while his hapless minions tramped around in the bush on his behalf doing the actual exploring.

As readers of my Wilbur posts will know, the geology along the K&P line is notable for its many mineral deposits--in particular of iron ore--and the region was surveyed extensively in the late 1800s and early 1900s for mine development potential. Other local deposits of interest include silver, gold, copper, antimony, mercury, and barite--all of which are found to some degree in the calcitic marbles at the Clyde Forks Deposit.

Now, before you grab a pick and rush into the bush, it's important to note that mineral claims are well staked across the region, including at this site. While I haven't checked exactly who currently owns the lease on this mine site, two claims were staked as recently as 1984 and probably remain on the books. Indeed, significant copper-antimony-mercury-silver-barite mineralization was identified at the site around that time. However, the deposits probably do not warrant commercial exploitation, which leaves this site as another interesting footnote in Lanark County history.

As Dr. Steve Brule says, "Check it out!"

The bush road leading to the mine site is overgrown, mud-holed, and rife with mosquitoes. Rather than ride it, I parked at a logging staging area and hoofed in the last few hundred metres with my GPS. The terrain in this area is lumpy and steep, with rocky outcrops and mixed hardwood forest. Not the easiest terrain to ride or hike across. I certainly feel for the surveyors who first came out here with chains and transits to take a bead on a claim.

Eventually you reach a clearing on crushed stone where it's obvious some kind of industry occurred. Here, the broken calcitic marble has not had time to weather and it stands in stark white contrast to the mossy rocks and general gloom in the surrounding woods. A campfire that seems to get regular use sits in the middle of the clearing.

On one side of the campfire is a large pit in the undergrowth. Some research identifies this as a test pit dug (probably by T. Caldwell's crew in 1918) to expose a mineralized barite vein. In fact, signs of several other test pits and trenches are visible in the immediate area. One carload of crude material from these pits was reportedly shipped to the U.S. for analysis.

Back on the opposite side of the campfire, a cool breeze emanates from a dark shadow behind the spruces. A closer look, and there is is: the mine entrance, or adit, at the base of the rock face--complete with a modern non-stick frying pan for intrepid visitors. Obviously this site sees regular visits.

The timbering at the entrance probably dates from 1969-1970, when the main exploration of the site was undertaken to assess the mineral potential. The location of the adit and the generally dry conditions in the area have helped to preserve the wood. Indeed, it looks to be in good condition, although I wouldn't bang on it. The rock appears to be very solid as well. A quick look inside is probably statistically safe.

My headlamp did nothing for me, since my eyes had insufficient time to adjust and I didn't think it was wise to hang around in the tunnel until they did. So I only looked in a few metres and took some pics with my iPhone on flash.

The workings are quite small. The tunnel extends straight in about 50 feet, bends slightly left and then proceeds about another 70'. At the bend a drift extends to the left about 15'. Twenty feet past the bend, a second drift extends left about 10 feet. The records (as shown in the pic below, taken from a petrographic study of the site [1]) indicate that grab samples of the barite were taken on the left wall near the tunnel entrance, near the end of the first drift, and near the end of the adit. The barite vein is apparently fairly obvious in these locations, although I was not equipped to identify it during my visit.

Near the entrance are some iron rods wedged into holes drilled into the rock. I'm exactly not sure what these were used for; maybe to provide a support for drilling or rock-moving equipment. Or maybe just a handy way to hang the rest of the kitchenware.

The petrographic study of the site [1] provides an interesting discussion of the mineral potential:

"An important feature of the property is the potential for gold mineralization in addition to the knownCu-Ag-Sb-Ba-Hg deposit. 

"The prospect is similar to several marble-hosted, disseminated, gold-pyrite-tetrahedrite showings in the area [...] Gold mineralization, at these occurrences, appears to be related to the degree of pyritization and/or silicification in marble host rocks. 

"In terms of the overall geochemistry and style of mineralization, the Clyde Forks Property is generally analogous to many large disseminated gold deposits in North America [...] such as Carlin, Cortez and Getchell in Nevada." 

So, there we go: Once again, the marble geology of Lanark County provides an interesting dualsport adventure. And a connection to Nevada, no less.


1. Petrographic Study, Clyde Forks Deposit, Lavant Township, Southeastern Ontario. Jurate Lukosius-Sanders. June 1987.

Sunday, June 29, 2014

Wait--new look?

As you can see, I'm playing around with the layout and design of this site. Blogger's tools are pretty awful, so bear with me while I figure out the best use of the available options.

Tuesday, June 24, 2014

Motorcycle insurance savings

The Personal offers some remarkable insurance savings over Intact, our previous insurer for home and auto (two cars). Today my WR250R coverage with Intact expired, so I transferred it over to The Personal as well. Here's the deal:

Intact coverage (on renewal):
  • $1M liability
  • Standard accident benefits
  • Collision $500 deductible, $300 comprehensive
  • Annual premium $603
The Personal coverage (new policy):
  • $2M liability
  • Standard accident benefits
  • Uninsured automobile accident coverage
  • Property damage
  • All perils, including collision $500 deductible, comprehensive $300 deductible
  • $1500 coverage for transportation replacement
  • Emergency road service
  • Worry free option
  • Total annual premium $125
Yes, that says $125. I was an idiot for not switching earlier. Including my new home and auto coverage (two cars), my combined annual premiums are now less than half of what they were with Intact, for better coverage overall. 

Monday, June 23, 2014

How to replace pivot bearings in a Santa Cruz Tallboy 2 Carbon

It's been a year since I got my Tallboy 2 Carbon, and a midseason tear-down a few weeks ago revealed the need to overhaul the pivot bearings. The 2014 model uses eight 7900 bearings: four with rubber seals in the upper pivot, and four with metal seals on one side only, in the VPP linkage. Although six of these bearings looked mint (nice clean grease), the top two bearings in the upper pivot had rusted out and one was completely seized. So no more riding until at least the two rusty bearings were replaced.

One of the details that attracted me to Santa Cruz in the first place was their attention to pivot design. Indeed, the VPP incorporates grease nipples to allow both sets of lower bearings to be flushed out with clean grease. The design works really well, but it can't overcome basic wear caused by hammering little metal spheres into tiny races. Over time, you'll get notchy pivots, which is exactly what I had in all locations. Notchy bearings makes it hard to adjust your pivot axles for that sweet spot between fluid smooth rotation and no side-to-side play. It was time to replace all bearings.

Santa Cruz offers a helpful overhaul guide and even sells replacement parts at a good price. In fact, replacement bearings are free, but you have to mail back your old ones. I ordered the Santa Cruz extraction tool (you only need the 7900 tool for the Tallboy 2), the bearing press, and a full set of bearings. Everything arrived two weeks later and I set to work. In retrospect, ordering new pivots with bearings installed may have been the cheaper option. Read on to avoid the frustration I faced!

First of all, these are the hardest bearings I've had to replace in all manner of vehicles and machinery. Although merely a press-fit, they are so tight they remind me of a certain obsolete submarine hull penetrator design adopted from the Trident missile program. To install the thing, you needed to soak it in liquid hydrogen. The metal absorbs the hydrogen and expands, allowing the parts to be slipped together. The hydrogen evaporates and the metal shrinks, creating an almost-welded level of watertight bond between the components. Clearly Santa Cruz has adopted this technology, because three hours of gentle and then increasingly berserk whacking with a hammer and the Santa Cruz tool did nothing except punch out the inner race. I was being mocked by a piddly bearing! By the end I had a pile of bearing carnage: balls, seals, races--all in a greasy pile.

The guide mentions that "some bearings may be hard to remove..." No kidding. I only succeeded in punching out the centre race, and then only in the four upper pivot bearings, with the Santa Cruz extractor tool. After that, the tool was pretty much worn out (or just badly designed), because there wasn't enough of a purchase on the back side of the outer races in the VPP linkage for the tool to grab.

Basically, the extractor tool is a waste of money. You can't even use a drift to punch out the bearings from behind, because the way the races are seated, there's no outer race visible from behind. Too bad there isn't centering spacer tube like in a few motorbikes I've fixed. Then you can tap from one side to extract a bearing, slide out the spacer, and tap out the other race. Even better would be a needle bearing design for high-impact locations like the top pivot. This is something I'd love to see on mountain bikes. Even bike shops hate replacing pivot bearings because it's such a pain in the ass on most bikes and you can't charge enough for the the hassle. My Santa Cruz dealer said there was a month-long wait to even book an appointment, and then would charge by the hour. This overhaul would've cost around $200-300 given the difficulty.

In this pic you can see the little Santa Cruz extractor and punch in the middle. The press is above. Compare that with the extractor tool below--the real solution.

While a blind bearing extractor is not cheap at $150, compared to paying my local bike shop it was a decent investment. The extractor uses a hardened steel collet that wedges with a threaded piece into the bearing area of the outer race. It doesn't spring out like the Santa Cruz tool. An integrated slide hammer allows you to tap out the race without risking damage to the pivot itself, because you're hammering away from the pivot. With the Santa Cruz tool,  you have to hammer towards the pivot. One slip and you can hit the pivot (or your finger) and damage something.

Installing the new bearings is fairly simple with the threaded press tool, but inevitably one bearing will go in slightly askew and it's hard to straighten. I recommend using an arbor press to push the bearings in square. Each time you press in a new bearing, you stretch the forged linkage slightly and over time it'll loosen up. Then you'll need a Loctite product to bond your bearings in, or have to replace the pivot altogether.

After all this hassle, pressing in the VPP bearings using the threaded tool resulted in a bit of a notchy feeling when I was done. Crap! For my last bike, I had machined a set of presses that pushed on the outer race of the bearing (rather than the centre) to avoid this problem. However, the Santa Cruz stock bearings don't seem to be well designed for this (in fact, some of the seal edges had snapped off during removal), so I'm going to look for some better quality after-market replacements (79002RS) with double seals and a bigger edge on the outer race, and make a press. I've never had these problems with any other bearings I've replaced, even cheaper Chinese bearings when the SKF or FAG models are way out of budget. I've also never had any other bearings blow apart just from tapping them in the centre race.

Update: Having used the blind puller for a while now, it's not grabbing the outer race as well as it used to. I'm looking for a better solution, such as a collet that fits better than the sizes included in the kit. I've also ordered a second set of pivots with bearings pre-installed. Now I can just swap pivots and get back riding quickly, and replace the worn bearings in the other pivots at my leisure.

When reinstalling the pivot axles, Santa Cruz specs tightening them to 35 inch-pounds. I find this is just a bit too tight when using my torque wrench (assuming it's still calibrated) and back them off about 1/8 to 1/4 turn. It's important they're snug but not tight, since the bearings are a radial design that requires preloading just like a headset. Too tight and they grind. When re-installing the centre lock bolts, Santa Cruz recommends 100 inch-pounds of torque. That's actually a lot of force; I just put a dollop of Loctite blue on the end and give them a firm torque by hand. Here's an official vid of the procedure.

To sum up:

1. Use a blind bearing extractor (collet style) to remove your pivot bearings. This reduces the risk of damaging your pivots and saves hours of frustration with the Santa Cruz extractor. The kit I bought is a universal Chinese set you can get from any budget tool supplier.
2. Use an arbor press (if available) to install new bearings. Or ask a machine shop to press them in for you.
3. Use a press that pushes on the outside race rather than the centre race (as with the Santa Cruz threaded press).
4. While Santa Cruz will replace your pivot bearings for free, you can get much better aftermarket bearings (e.g. 2RS for the upper pivots) for not much money. All bearings will wear out from constant impacts over time, but at least the 2RS will resist water ingress better. And all but the cheapest bearings are more likely to come out in one piece when pressing only on the centre race.
5. Consider buying the replacement pivots with bearings preinstalled. Santa Cruz offers these parts at a surprisingly good price. Then you can just swap out pivots and take your time to replace the alternate set of bearings at your leisure. I think I may go this way in the future, so I can spend more time riding and less time waiting for parts.
6. Tighten pivot axles to 35 in-lbs, lock bolts to 100 in-lbs.

Thanks to Joe at Santa Cruz who patiently answered my tech questions.

Thursday, June 19, 2014

MTB Chicks ride Almonte Riverside Trail

One of my biggest joys in building singletrack is watching others enjoy it. Last weekend I had the opportunity to see just that, and take pics of a ride organized by my friend Lisa Labonte of Vamos Outdoors as part of Mississippi Mills Bicycle Month.

More pics on my Flickr page.

Update on Heidenau Scout + Tubliss

I'm not sold on my Tubliss conversion. Although I haven't had any leakage or flat issues (in fact they hold air way better than tubes ever did), balancing the front wheel has been a real pain despite adding almost 100g of weight and Slime. After almost 2000km of riding on-road, the remaining vibrations have become more than a nuisance and I'm debating whether or not to revert to a tube with Stans. It would certainly be simpler and lighter.

The problem is the weight of the rim lock and dual-valve arrangement, focused in one region of a 21" rim. Yes I can keep adding weight, but when you consider what's already on there (plus the Slime!), it should be balanced by now. Maybe I'm just being picky, but sustained road vibration at a constant frequency just seems to get under my skin, unlike the random bumps of trail riding.

Meanwhile, the Heidenaus themselves are working out great. Lousy in the mud (duh) but surprisingly  good in the gravel.

29er tires: Mavic CrossRoc Roam 2.20

My Santa Cruz Tallboy Carbon came with the Maxxis CrossMark LUST tire, which is arguably one of the worst options for any kind of XC riding except on buff hardpack. My first clue came just a week after getting my new bike, when a random rider at Kingdom Trails derided their charms. Now, having ridden the damned things for a year, I agree that the side knobs are lame and vague when cornering, and the mainly continuous centre ridge, despite offering low rolling resistance and decent tracking under ideal (hardpack) trail conditions, is slippery as hell on anything damp and pretty much useless in mud. Rocky descents and tight rooty single track are doable but not confidence-inspiring. 

Then my rear tire got a gash and couldn’t be patched, so it was just the excuse I needed to try something new. Strong contenders were the Maxxis Ardent, Aspen, and Ikon, and the Kenda Slant 6. In fact the Slant 6 was my first choice until I saw just how minimal the tread is. Probably fine on slickrock, but not for my trails. Then the guys at Phat Moose pointed me to the all-new Mavic CrossRoc Roam

Here’s a tire that’s UST compatible, has a relatively low centre tread for speed, yet large side knobs for more cornering grip. It has a beefier appearance than a pure race-light XC tire, but isn't as ponderous as something like the Kenda Nevegal (which I used to ride and loved on my 26er). Although I didn't measure it, the 2.2 appears to be a full 2.2” wide (noticeably wider than my CrossMark 2.1) and features the most durable of three rubber compounds that Mavic offers. That should stand up to the many sharp-edged rocks in our neighbourhood. And at 780 grams and 66 tpi they are 55 grams lighter and likely stiffer than the CrossMark LUST (835g/120 tpi). Not bad for around $75 a hoop.

Found a sealant gremlin while changing out my old tires:


Rode them for the first time today. Trail mostly hardpack, some rocks and a little bit of mud that had dried into a wonderful play dough consistency. Couldn't really crank it because of a leg injury, but the tires felt good. Fast and quiet on pavement and packed dirt, and the wider footprint and side knobs gave way better control through the mud sections. Cornering felt more predictable without the sensation of a rolling drift that the CrossMarks gave. Decent traction on rocky ledges. The stronger side knobs gave more support when hitting obstacles on edge, as sometimes happens.

Both the front and rear tires had gone flat after sitting for two days since I mounted them, which I  expected because the sealant hadn't had a chance to slosh into the bead area. Pumped them up to 28 front/30 rear to allow for some leakage on my first ride. This is harder than I normally ride tubeless so they did bounce around a bit, but not as much as I expected. Didn't lose any air though. Must've gotten enough sealant into the bead to finally seal them up.

Overall I'm pretty happy with these tires and am looking forward to a longer test ride at full speed and power, probably a few pounds lower to reduce bounce.

Update 2 (Aug 1, 2014)

Have run them through soft mud, hardback, loose gravel. Recommended pressure stamped on tire is 29 psi, but I find they're too bouncy at that pressure and work better a little softer (maybe 25 psi - still experimenting). Good grip and control in the front, not sure they make the best back tire. In the rear, straight line grip is excellent, but when cornering, I find the back end will suddenly hop out a bit at a certain lean angle, probably on the transition to the edge knobs. Then the back end becomes a little vague. This could be my mediocre riding style (I'm not super technical, but can usually make up with speed and power what I lack in finesse).

Update 3 (Oct 5, 2014)

I've found that 25 pounds of air in rear with 24 lbs in front, with 180/80 lbs of air in rear shock/fork is the magic formula for my Tallboy to come alive. However, I've come to the conclusion that while the CrossRoc makes a decent front tire, it doesn't perform well on the rear. The side knobs tend to let you ride partially up an obstacle like an off-angle root, only to then to deform and pop off, throwing you sideways when you least expect it. A shorter knob would skip off earlier and not lead to that kind of surprise. This is mainly an issue in the kind of wet, rocky, rooty stuff I ride in the Ottawa area. Both tires work much better in the sandy/grippy dirt of Kingdom Trails in Vermont. Rode with some other guys today who find the Maxxis Ardent is the special sauce for our local trails, so I'm planning to give one of those a try on the rear. They have shorter side knobs and should therefore be more predictable.