Friday, October 28, 2011

The Right Tool

I've been into single speed's for some time now. In various past posts on this very blog such as this one, this one or particularly this one I've chronicled some of the adventures, details and thought process behind the whole one geared mentality. The synopsis is that it's different, it's simple and it's fun. I realize, anyone who has spent much time on a SS bike knows that there is next to nothing simple about them but once you get the multitude of setup issues debugged and once you progress from cobbled, to dedicated SS bikes, it starts to be more fun than frustration.

Why not cobbled you ask? The bottom line is that virtually all of us started that way. Heck, back in the day (the day was like 12 years ago in my case) there were virtually no dedicated SS frames, at least not for the MTB which was all we were riding back then. Instead you used some sort of tensioning device like the new to the market Surly Singulator or you just cobbled an old derailleur with extra long limit screws so you could lock it out in a given position. The former actually worked really well but was shunned by the staunch SS purist crowds. The latter worked, poorly, and failed frequently.

Soon we were getting dedicated bikes with slotted/horizontal rear dropouts. This was great but required BMX tensioners in most cases in order to work really well which also meant a nutted, solid axle. That pretty much sucked but was the norm. Disc brakes further confused this issue because the caliper needed to mount consistently based on the axle position. Eventually people started using slotted/ovalized caliper tabs on the frames, which got the job done. Having gotten sick of that setup and really liking the ability to use regular wheels with spacers on the freehub body and a single, easily changeable and cheap cog, I've gone primarily to Eccentric Bottom Bracket (EBB) designs. This is the worst design in the world for tensioning chains, except for all of the rest. Well, actually, the pivoting and sliding, vertical (normal) rear dropout designs are really the best bet. Unfortunately, they are hard to find and tend to be on expensive frames.

With the advent of BB30 and now PF30 compatible frames, you can get an aftermarket EBB adapter that allows you to run a normal frame with normal wheels as a SS bike. I love this idea and have started adopting it. The plan is to convert Cathy's SSCX bike over as well. Another project for another day. For now we will have to stick with what we have though, her horizontal dropout, bolted axle Kona Major One SSCX.

So anyhow, the whole reason for this post was basically, mud. It has been raining like mad recently and the conditions have been horrible. Last weekend the Downeast Cyclocross in New Gloucester, ME was absolutely brutal. I'm usually pretty good in the mud but last Saturday was the kind of mud you just couldn't ride and you had to run, frequently. Literally half of the course you would ride 100' and then run 100' and repeat. I suck at running so was pretty darn mediocre at the race Saturday.

On Sunday the conditions were a little better and I was having a pretty good day. I could ride sections a little better than many and made up lots of ground. That was, until I was riding a mud section that I thought I really should probably be running as it was really deep and had lots of grass pack in. Just as that thought was going through my mind, the rear derailleur sucked into the rear wheel and ripped off the bike. Ugh! I started running with it and soon blew up. I stopped and fished the derailleur from the spokes of the rear wheel so I could push the bike and started running again. The pit was about 1/3 of a lap from where I broke down and in that time I lost about 10 positions. Fortunately my pit bike was set to go and I worked as hard as I could to make up spots. At first it was tough given how gassed and disoriented I was from running but soon I recovered and got into a groove. I managed to gain back all but 5 of the spots and salvaged the day, to a degree. The bike, my good one of course, was mostly OK. A new derailleur hanger, some straightening and cobbling of the rear derailleur and truing the rear wheel (which meant pulling the tubular tire to access the internal nipples) and replacement of some cable housing and the bike was back together. Ready for next time.

When you ride muddy fields with a cyclocross or any other bicycle, a few things become apparent. First, bikes really are not made to ride in that crap. Beyond the issues of bearing contamination and all out destruction, we have an open and fairly fragile drivetrain. The rear derailleur, hanging perilously close to the ground from the tiniest little mount seems destine for failure. When you add grass into the mud, the caged jockey pulleys of the mechanism seem to have an attraction that can not be broken. The grass packs into the pulleys and bunches up, Rim brakes are another problem spot, as they are poorly affected by the mud and water but also because they like to clog up with grass, mud and debris as well. Add to this the fairly narrow openings affording small clearance of the chain and seat stays as well as the fork bridge and you have a whole lot of places that can and do pack in with power sucking mud. This is just a really bad design and a good example of the wrong tool for the job.

As such, I decided that for the upcoming Orchardcross SSCX race this Sunday, I was going to do a test. I figured that I would try and put together a bike that was better suited for the mud as we are virtually guaranteed to have a really nasty course this coming Sunday, given the rain and snow predicted for the weekend coupled with the rain and snow that we have already had this week. What I did was to take my SS 29er MTB and monster-cross it. I like the idea of a SS for a really muddy race in general. If you can gear it low enough for the mud and still be OK for the dry sections, I think you would have a huge advantage. I say this because the drivetrain is simplified to the point where it should be much less impacted by the filth. A normal SSCX bike still has the clearance issues though. A SS MTB however, especially if you run normal 35c CX tires on it has a ton of clearance. The mud may still pack in but no where near as badly as with a CX frame. Lastly, the MTB takes advantage of disc brakes, which tend to not clog with mud and crap as they are fairly isolated from the ground, where the mud and grass is, being that they are in the middle of the wheel.

My one question is going to be in the handling. I think that riding mud with the wider MTB handlebars will be a bunch easier and climbing should be as well. I find that I get better leverage with the MTB bars. Cornering may be problematic as a 29er MTB isn't exactly fast handling when compared to a cross bike. I guess I'll see though. I plan to bring both bikes and will try each and see if I can get a comparison. Who knows. I'm hoping this might be the right tool for the job though.


CB2 said...

I totally suck at cross, but my best CX race ever was on my 29'er singlespeed.

mkr said...

It's funny but the MTB just feels comfortable and familiar. The cross bike feels good but never as good as the MTB.