Monday, May 21, 2012

Trek 700 "overhaul"

I own two bicycles and the oldest is a 1990 Trek Multitrack 700. Back in 1990, the concept of a hybrid bike--the combination of road bike and mountain bike--was fairly new, so I think they named this particular model "Multitrack" to help people understand why it was different. Today my bike is different not because it is a hybrid but because it is so old.

I don't know how many miles are on this bike. In the last 22 years I've had at least three bicycle computers, and as each one fails, it loses the odometer reading. My current odometer is around 600 miles. The last cycle computer didn't last long because a squirrel chewed through a wire and there was no way to repair it. But at that time (2006) I was regularly commuting to work on that bike and doing some other rides, too. So I easily had anopther 500 miles on it. In high school (1990-1992) I rode a lot, then I only did scattered rides in my college and grad school years. So adding another 800 miles I get a sum of at least 1900 miles. That's actually not a lot of miles at all for a 22 year old bicycle.

But it is a lot of miles for the drivetrain, specifically the chain. I didn't know chains could wear out until last year when someone at my bike shop told me I had a worn chain. According to Todd Downs, "as the chain wears, the inner surfaces of the chain's pins are slowly ground away, effectively increasing the center-to-center distance between the pins" (p.174). This causes the chain to elongate and not fit into the teeth of the cogs that make up the chainset and rear cassette. As I said, I hadn't noticed this until someone pointed it out. But upon inspection, I saw daylight between some chain links and my cog's teeth where there sould be none. So, off to the repair shop for a replacement chain!

Rear Cassette
I also read in Todd Downs' book that "putting more than 1,500 to 2,000 miles on a single chain and cogset will most likely [result in the] need to replace the entire cassette and chain at the same time" (p.164). Uh-oh. I put a new cassette on the list for my bike shop to tackle. I was concerned that the front chainset would also need to be replaced, as I saw the middle chainring had some broken teeth. To my surprise, the bike technician said the chainring had always been that way. The design includes having the middle chainring with a couple ground-down teeth so that the chain shifts more easily from one chainring to another. Well I'll be. I learned a lot today at my bike shop!

I still had two more items for the bike technicians to fix. First, I complained that the rear brake squealed whenever I used it, and it didn't seem that strong anymore, either. Remember, this equipment is 22 years old! The technician looked at my brake pads and didn't see excessive wear, and the rubber still seemed pliable. So he said they'd adjust them. I note on the work order that he didn't mention the squeal, so I hope they fix that.

The last thing on my list was the shifter. I showed them how the left shifter tended to skip the middle chainring so that I would downshift straight from gear 21 to gear 7 (rather than 14). When riding, this causes me to lose a lot of speed as I approach a hill. I can get to gear 14 by gently pressing the shifter, but not always. Hmmm. The technician diagnosed the problem quickly. There is some tiny part inside the shifter that is broken or otherwise not functioning right. He said they's take a look and see what they could do, but otherwise the only solution would be to replace the entire shifter/brake lever. "That would be really expensive," he said, and he seemed to dismiss that possibility outright. I appreciate his honesty and respect for my wallet's resources, but I wish I had pressed him on what "expensive" really meant. In my mind, I had already saved some expense by him telling me that my chainset could be spared. He had also relieved a concern I had about my bottom bracket, and he didn't think my brakes needed to be replaced, either. I entered the bike shop thinking my bill would be about $200--about half of what it would take to replace the entire bike with a new one. I left the bike shop with an estimate of $100. So expensive or not, I was actually ready to pay for a new shifter if he had given me that choice. Ultimately, I may have to do that anyway, but in the meantime I'll see what they can do.

Something I crossed off my list before getting to the bike shop was an adjustment to the kickstand. My kickstand was loose on the frame and while I can temorarily fix that by tightening the bolt, it always gets loose again. Yesterday I took off the kickstand, cleaned it, and tightened the bolt again. I noticed the washer that goes on the bolt was cracked, so I assume that is the problem. It is not producing enough friction to hold the kickstand mounting bracket in place. I felt kind of silly asking the bike shop to replace a washer for me, so I've elected to do that myself when I get the bike back.

They had to order a part, so the shop will have my bike for about 10 days. Meanwhile, I've got my Trek 1.5 road bike to keep me happy.

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