Day 5- Chain rings, derailleurs, cassettes, freewheels

We started the day with understanding the workings of rear and front derailleurs. As most of you know, the purpose of this simple mechanism is to "de-rail" the chain, thus moving it to the next ring (front) or cog in the rear. As I have also de-railed my chain completely off the front ring both inboard and outboard, I have not always seen this mechanism as "simple"! Our learning objective was to demystify the mounts and adjustments. The rear derailleur is simple as there is only one location with a single bolt to mount it. Now if the mounting location is damaged.........well, that's where derailleur hanger gauge and alignment tools are necessary. We used these tools to check our frames before reassembling.

Knowing the chain line dimension is important to correctly mount the front derailleur. We used our vernier calipers to determine the dimension on our frames. And, yes, in this picture the front derailleur is still off the bike.

The front derailleur mount is actually very simple dimensionally, but the adjustment is more complicated than the rear, because everything is done under cable tension (unlike the rear).

With some care, we got our adjustments completed on the road bikes and then proceeded to do exactly the same procedures on the mountain bikes at our benches.

Friday ended with a successful sign off of all the week's procedures. Every bench task is signed off by the instructors when correctly finished.

Off to Siskiyou Cycles to procure my weekend ride....