Trek 620 650B conversion

One of my projects over winter break has been to convert to my old Trek 620 to 650B wheels. For mountain bikes, I don't see any special value for 650B wheels over 26", but for road bikes, they really do open up some new possibilities. In my case, my Trek didn't have much clearance for fat tires and fenders with either 27" or 700c wheels. The smaller diameter should fix that.

The key to a good 650B conversion is... math. The 27" wheels I had lately on the Trek have a bead seat diameter of 630mm. A 650B wheel has a BSD of 584mm. Subtract those two numbers (630-584=46) and divide by two to look at the radius (46/2=23) means I need to look for a brake with 23mm more reach than the current calipers I have on there. My current brake reach is about 47mm (front) and 53mm (rear), meaning I need a brake caliper capable of 70~75mm.

I ordered up the parts earlier this month, just about doubling the initial $300 I spent on the Trek:

Did it work? I'll save you the heartache of anticipation right now, and tell you it transformed the Trek into my new favorite bike. Read on.

A Weekend Chock Full of Biking (Sette Razzo, ERB)

I should probably spend these days finishing up my Christmas shopping, but it was cold enough that the trails had a decent freeze on them, but not so cold that riding is complete misery. Best to get outside then while I can.

Saturday, I headed to Chestnut Ridge for my second chance at a fat bike demo. Er, except, where's the demo fleet?

Fat Bike Demo Day (and more ERB as well)

This weekend, our friendly local Trek store had a fat bike demo. We had a pretty full weekend at home, but I managed to get out to Alum late Saturday morning. Alas, all the Large and XL bikes were out, leaving only a medium Pugs available to ride:

Two sizes too small for me, but I got tired of standing around waiting and took it for a quick spin. Compared to the Moonlander I test rode a few years back, it was quite a bit better, more like a mini Krampus and less like riding a beach ball bouncing down a flight of stairs. Still, the 3.8" tires didn't seem to give more cushion than my 29+ tires, and it didn't seem to have quite the indomitable rollover of the bigger wheels.

New Tires and Cupcakes

Sparked by some black Friday madness, I've been on a tire buying binge lately. A place in Indianapolis had 25% off and free shipping, so I loaded up my order with tires. Starting at the front, I picked up a 26" Dirt Wizard, because... I'm not sure why, but I put it on the front of the ERB:

No ride report yet, since it's been raining pretty much non stop for the last 24 hours, but I'm always happy for a chance to use my swanky Bontrager scandium wheels.