Thursday, July 28, 2016

What the Cog?

It used to be that the big gears on a bike were up front and the little gears were in the back. This has all been turned upside down now. Bikes went from two chain rings to triples, back to doubles, and now 1-by drive trains seem to be the norm in the MTB world. Funny how the pendulum swings like that. And people just gotta have that latest setup too. I think 1-by drivetrains are stupid.

I ride a variety of terrain - uphill, downhill, dirt roads, pavement. A mountain bike works on all of it. My Santa Cruz Tallboy has a 2x10 drivetrain, meaning a small and large ring up front with complement of 10 cogs in the back. I use all of those gears regularly. I could use more gear on both low and high ends, actually.

Sometimes on the road, I spin out with a tailwind or heading downhill. A bigger ring up front would be nice, like a triple. But then on the other end, I could use an easier gear or two for some climbs. If a double crank is not enough, how could a single ring drivetrain possibly be enough. Yeah, the mocho types say just grow a pair and tough it out. How about join me on a 5000ft climb to 13,000ft in Colorado with your 1-by?

The predecessor to my Tallboy was 26" wheeled with a triple crank. The 22:34 ratio gave me a 16.8" gear. Then 29ers came around, and the industry graciously gave us a 36t cog to ease the burden of turning that wagon wheel. But they also took away the triple. The new ratio of 24:36 with the bigger wheel pushed gear up to 19.6", a 17% jump! That is almost two gears harder on the low end. Two hour long climbs at 3mph already hurt. I didn't need them to hurt 17% harder.

So now new frames are being produced that are not even compatible with front derailleurs. This will limit selection of future frame purchases for me. Again, to mitigate some of the impact of loss of range, the industry now provides 42t cogs! Cogs have now become bigger than rings on most mountain bikes.

New 42t cog on left to supplement a 36t cassette with BIG ring on right.

When I mate a 42t cog to my 24t ring from my double crank, I get a 16.6" gear, pretty much right back to where I was with a triple crank on a 26" wheeled bike. Nothing I regularly ride around here requires such a low gear ratio. Only a ski area service road or two I infrequently hit might benefit.

Several companies now offer conversion kits. I went with One Up. Basically, you start with a standard 36t, 10spd cassette. The largest cogs are all bonded to an aluminum carrier. So you first slide on the 42t cog, then the cassette, but leave off the 15t or 17t ring to keep cog count at 10. Rather than have a big gap from 19 to 15 or 17 to 13, the kit includes a 16t cog, so you remove 17t and 15t cogs and add the 16t. This way the steps are 19-16-13. Still biggish steps, but not huge.

I head to Colorado for two weeks in September. There are several climbs out there that will see heavy 42t cog usage. Carson Rd up to highest point on the Colorado Trail, Black Bear Pass in Telluride, Maybe Gunsight Pass in Crested Butte are all motivation for lower gearing. Amount of hike-a-bike will be reduced and the legs will be fresher to ride again the next day.

The Tallboy will be going with me. It had developed a nasty bottom-bracket area squeak the last couple rides. Pulling things apart, the BB itself was buttery smooth. No delamination of alloy inserts in carbon frame either. I next moved to the VPP (Virtual Pivot Point) bearings. Pulled the assembly apart and found the bearings trashed.

I was not surprised, I had logged over 8100 miles on this bike so far and these were still the original bearings. I have never even ridden a third this many miles with my other full-squish bikes bikes without having to replace bearings or bushings. The Enduro Max bearings and grease fittings on the pivot link are key to the longevity of these bearings.

I already had the bearings on hand, as I had just replaced the upper rocker bearings because they were developing some play, which bugged me. The VPP bearings were so gone they fell apart when I tried to press them out, making it a heat and punch operation for removal. What a PIA. New ones went in fine, but the outer rubber seals that are not part of the bearings were trashed.

Hunting online, these could not be found anywhere, including Enduro Fork Seals, where I bought the bearing kit. So I emailed Santa Cruz service department inquiring where I might find them, as their online store didn't have them either. I got a quick response saying four were in the mail to me. How awesome is that?

Saturday, July 23, 2016

Campton Boondoggle

The forces to be conspired against Dave and I getting a decent trail ride in today. For starters, a pick-up lost control on I-93 and nearly took us and a few other cars out. Presumably distracted driving. The forecast was less than perfect. At the very least, it was going to be gross hot. Maybe the pop-up thunderstorms predicted would be a good thing.

Our planned route would hit four major climbs and several lesser climbs. Not a minute into the ride, we stopped, A cub bear was along the road. Where was mama bear? I'm seeing more bear these days. The first climb was Campton Mountain, nearly all paved now. Starting from the Campton dam, it is always a kick to the groin with no warm-up and grades approaching 20% with 1200ft gain. Chamois was already saturated just a few miles into a nearly 50 mile loop.

Where is your mama?

Cub turned around and ran back into woods as we approached

After bombing down Campton, we headed over to the Welch Ledges. There is an alternative trail up to the ledge that starts out on an old logging road. The grade is just manageable in the lowest gear.  It had rained on Welch-Dickey overnight, and with the humidity, some of the slab was still wet and uber sketchy. A number of hikers were on the ledge taking in the view.

Dave heading up to the Welch Ledge

View from Welch Ledge into Sandwich Wilderness

Dickey Mtn and the upper ledge

After a treacherous descent back down to the valley, we headed into the Smarts Brook area to hit some established and not so established trails. No sanitized trail here. Very rough wilderness feel to the riding, every rock, root and slab felt. A dismount every now and then was required. After passing by scenic Atwood Pond, we popped out on seasonal Sandwich Notch Rd for a few hundred more feet of climbing before cresting the notch.

Riding in the Smarts Brook area

Fine gems of trail in Smarts Brook area

Bombing down the other side of Sandwich Notch is so much more fun on full-squish mountain bikes than cyclocross bikes I often ride on this road. Can pretty much ride WFO, that is until a jeep comes around the bend and the road is only wide enough for a jeep...

We followed the Beebe River for nearly 10 miles down stream on the gated Algonquin Rd two-track. Love that section. Minimal pedal input can net you 20-25mph speed much of the time.  The skies were looking more ominous by the minute though. That 30% chance of rain was looking more like a certainty.

Algonquin Rd along the Beebe River. Ominous sky building.

We next wrapped around Mt Prospect on Perch Pond Rd. This is an open auto road that we hoped would recoup some of the excess time that went into the challenging trails thus far. But 3500ft of climbing in 15 miles put a dent in the legs.

On the way to Mt Prospect, we cut through on Town Farm Rd, another two-track that eventually necks down to a narrow trail. It is here where the thunder started booming and the skies opened up. Dave and I were so hot and gross by that point, the rain was welcome. The temp dropped a bunch too. We were surely going to run out of water before the end of the ride, and anything to cool the body down would help preserve limited water reserves. I did pack my filter just in case.

The small storm cell petered out just as we got to the Mt Prospect climb, another 1000 footer that I have never ridden. Some photos suggested it would be a buff cruise to the top, where there was a nice outlook to the lakes region. It sure started that way, albeit steep approaching 20% grades. Then it got steeper. Then it got rocky and rooty. It is one of those climbs where, if you are in the right stated of mind, you grit your teeth and just get it done. I didn't clean it to the first outlook, but rode maybe 98% of it. Dave was less enthused with that kind of material placed late in the route. I think I heard him cursing the Hill Junkie.

Outlook from Mt Prospect, northern lakes in distance. Thunder was booming nearby
just to the southwest of here.

Dave on summit lollipop loop. We were probably off the bike as much as on.

Prospect summit loop

Upon reaching the outlook, Dave commented he wouldn't need to do this ride again if this climb was part of it. I thought wow, that was super hard, not a whole lot of fun, but rewarding by cleaning so much of it. That was before we started to take the little lollipop loop around the summit. Ugh. Lots of hike-a-bike. Hmmmm, perhaps when I ride this again, I do not need to ride the summit loop.

The descent was a test of brake caliper heat handling. Wow, don't think my wrists ever got so sore from brake pump. Popping out on road we had only one more "wee" bump to hit before final plummet to cars: Page Hill. I think Dave was all set on climbing for the day, and I may have heard more HJ cursing when I turned right for the two-track Page Hill finish instead of just following paved Rt 175 all the way back to the car. At least Page Hill is manageable, steep, but not crazy, and well maintained. I've ridden my cross bike at least a few times over that bump.

Parked along the Mad River, first order of business was a soak to remove 48 miles of grime and bring the body temp back into normal range. The water was so warm it almost wasn't refreshing. Was hoping for more of an ice bath sensation. But it was heavenly nonetheless.

There's body in the Mad River!

The short drive back down I-93 was not without issues either. Near Hooksett tolls, traffic stops, and all manner of rescue vehicles fly by. Accident. Great. I think most trips coming back from the Whites have me hung up by an accident. Looked like single pick-up roll-ever, very nasty, maybe passengers thrown from vehicle. Another distracted driver like on our way up? Don't know. I'm becoming increasingly leery of driving on that road.

What's worse than gas station burritos? Gas station hotdogs!
Hot dogs and a whoopee pie Dave bought me for post ride refuel.

Anyway, it was a great exploratory ride, if not a bit of a boondoggle. GPS logged 48mi with 7200ft of climbing in just under 5hrs moving time. I really enjoy getting off the beaten path once in a while. Good for skill maintenance, good for the psyche, and makes you appreciate the work NEMBA puts into other trail systems around the state.