Friday, February 13, 2015

Crashed: Nitto vs. Surly



So, I crashed yesterday.  In my history of crashing bikes, it was a relatively minor one.  The bike took most of the damage, and I escaped with minor road rash and a couple of bruises, and after getting the bike rideable again I was able to ride the ~10 miles home with pretty much no problem.  I'm thankful for the bike taking the damage, as my last couple of crashes have seen the bike pretty much unscathed and me damaged (the last one enough to land me in the emergency room and five staples in my knee).  Furthermore, the way the bicycle was damaged is pretty interesting.  Blog gold!

First, the details of the crash: I was riding my Long Haul Trucker along one of the levees that separates the American River from the Sacramento suburb of Arden, paralleling the American River Trail that runs from Sacramento all the way up to Folsom.  The levees can provide a fun alternative to the paved trail sometimes, since they are usually paved with gravel.  However, the stretch that I was riding on had become so hard packed that it felt as if I were riding on pavement, so I decided to cut back to the River trail, using one of the paved connector ramps that connects the trail to the levee.  The particular one that I decided to use was at an oblique angle to my direction of travel, so it required a sharp turn to enter.  Basically thinking I was on pavement, I didn't slow down much for the corner and took it with much exuberance.  I immediately regretted this decision as my front wheel lost traction on the less-hard packed gravel along the edge of the levee and I went ass over teakettle down the ramp.

Picking myself up and ascertaining that the bike had taken more damage than me, I set about righting it so I could ride home.  The front end of the bike had completely jackknifed around, with the front wheel turning more than 90 degrees to the right.  Normally, the front end rotation is limited by the bottom corner of my handlebars hitting the top tube, and by the front rack hitting the downtube.  Both handlebars and rack are made by Nitto: 58cm heat-treated aluminum Boscos and a chromoly M18 ("Mark's Rack") with the standard aluminum struts, respectively.  So, the crash really turned into a grudge match between my Nitto bits and my Surly frame.

Round One: Bars vs. Top Tube




In the battle of bars vs. top tube, the bars definitely won.  Whereas their rotation is normally limited by the top tube, the force of the crash was enough to push the bars past the top tube, so much so that I actually had to pull the stem off the steerer so I could turn the fork forward again.  When the head-treated Nitto aluminum met the double-butted Surly 4130 chromoly, the steel was the first to give.  As the bars contacted the top tube, the force (very minorly) dented the top of the top tube, while the bars escaped with a barely-noticeable scuff to their underside.  The dent happened right in the middle of the tube's length, right where you would expect the wall thickness of the butted tube to be the least, and it is a very gentle dent.  I actually didn't even notice it until I got on the bike to ride home and was looking down at the tube from above, and noticed the distortion in the tube's finish.  I have zero qualms about continuing to ride this frame now, one of the beautiful things about a material like steel.  It also goes to show the quality and strength of the Nitto handlebar, and why their are well worth their price.  In terms of swept-back bars appropriate for a high-performance upright bike, they really are without equal in their ability to hold up to the demands of enthusiastic riding (which, occasionally, includes crashing).  Many lesser swept-back bars intended for "casual" or "city riding," made from plain aluminum, would not have fared as well and would probably need replacing after such an incident.

Round Two: Rack vs. Down Tube


In the second round, Nitto didn't fare as well.  The front rack swung around with the fork and hit the down tube of the frame.  The best I can ascertain, the rear/upper struts of the rack (I use a four-strut mounting on this fork, seen here) hit the down tube right where the down tube cable stops bolt up.  The force badly bent all four rack struts, and twisted one of the mounting tabs that connect the struts to the rack platform.  These struts are solid aluminum, but probably not heat-treated, given how easier they are to manipulate when you are installing the rack.  The down tube, on the other hand, shows no signs of damage, even after removing the cable stop and inspecting underneath.  This impact happened much closer to the tube junction, so I assume that the wall thickness of the tube was greater here than where the impact happened on the top tube.  Since the rack was pushed against the tire, I needed to remove it in order to ride home.

I definitely need to replace at least the rack struts.  I haven't decided whether or not to replace the entire rack or try to straighten out the bent tab and re-install this platform with new struts.  Usually, I use an extra degree of caution with stuff mounted to the front of the bike, since something failing up there has the potential of stopping the front wheel suddenly, which causes a much worse crash than something stopping the rear wheel suddenly.  However, given the general beefiness of the rack platform and the redundancy of the mounting on this bike, it might be safe to ride still.  In any case, bike funds are pretty low right now, so it may be a while before I get around to doing anything.

In general, I'm really happy with how the damage from this crash shook out.  My injuries are minor, and I feel relieved that in the confrontation of handlebars, rack, and frame, the rack took the worst of it, since while not having a rack is convenient, it does not affect the rideability of the bike in any way.  I was also sure glad to have my rear rack and bag on the bike too, since I was able to just strap the damaged rack to my saddle bag, strap my front bag to the rear of the rear rack, and ride home with no issues.

Now, I wonder if there are ways I could substantially increase front-end traction in these situations, or if I just need to be more careful going around corners with sketchy surfaces?  Or both?