Thursday, November 8, 2012

Flat tires -

Today at lunch time, I was heading home to swap the bike for the car (needed the car to run an errand later in the day).  As I got to the first traffic light just a few hundred meters from my office, I noticed a slight increase in rolling resistance as I came to a stop. I looked down and sure enough, the front tire was flat. Shit... I just wanted to get the rest of the season out of this old tire. Just a couple more weeks! Fuck it, I moved my ass to the back of the seat and rode the remaining 3 or 4 Kms across town to get home. 

I had a few minutes, so I quickly put the bike on the stand and pulled the wheel off. I put it in the basement where it could warm up a bit (it's been a few degrees below freezing around here this week).  After work, I removed the tire and tube from the rim. It was pretty easy to spot the problem: the valve stem had ripped free of the tube. Colder temps are definitely tough on tires and tubes. I've been running 15-18 psi lately, and it probably began to tear away when I left the house this morning in the minus 8 Celcius frost. 

Oh well, I happened to have two brand new front tires sitting in the basement: a Pirelli Scorpion Rally and a Dunlop D606.  I bought both because I figured I would use one on the WR, and the other on the DR.  For no particular reason, I decided to mount the Pirelli. There were still a few miles left on the old D606, but as long as I had it apart, and as long as I was using a new heavy duty Fly Racing tube, I figured I might as well use a new tire. The old tire was more or less finished. Would have been nice to ride out the rest of the season and mount the new tire over the winter as I had been planning.

Valve stem separated from the MSR ultra heavy duty tube

The new 90/90-21 Pirelli Scopion Rally. This rubber is supposed to be a little softer compound than the Dunlop D606. 
I do like the 606 a lot, and it looks like a more aggressive tread pattern than the Pirelli, but lots of people have had lots of good things to say about the Pirelli. It's a popular choice among Dakar racers apparently.

Just a month ago, I had a flat rear tire. Here you can 
see a rusty nail sticking out. When that happened, I 
pulled the tire off and used a new Kenda Tuff-Tube 
size 110/100x18. The tire was a less than 1/2 worn Dunlop D606, size 120/90-18.  At the time of this photo, this rear tire probably had 4,000 Kms on it.  Still 1,500 left, maybe more.

I like the meaty look of the D606. It's a serious 
grass shredder yet is remarkably stable on paved roads.