Alanf’s blog…
Scattered thoughts

Tuesday, December 7, 2004

Box of Shame #2: change your sprockets…

Author: site admin
Category: The Box Of Shame

In the summer of 1994 I was helping out a few friends that were racing in the WERA and AHRMA roadrace series. One of these was my buddy Ray Hixon who was racing a heavily modified Honda FT500 Ascot (in an FZR400 frame, with a strange combination of Harley and Honda bodywork). One weekend, there was a WERA regional race at the Talledega Grand Prix track near Anniston, Alabama and I agreed to be part of Ray’s pit crew for the day as a warm-up for the Pro races later in the summer.

As it just so happens, there are some great roads for riding motorcycles near there in the Mt. Cheaha State Park, so some friends and I decided to ride over in the morning so we could enjoy the roads and then we could all help Ray out during the races. My GSXR was in need of some routine maintenance, including a new chain and sprockets but I didn’t have much time. Instead, Saturday night I did an oil change and just stuck on the new chain and figured I’d replace the worn sprockets when I got back. Just in case, I threw the sprockets into my tank bag.

Myself, my friend Troy and his brother Dean left Atlanta early Sunday morning and took some back roads to the Alabama border. There we met up with my friend Michael, who drove down from Huntsville, and the entire group of us headed to the track over the twisty roads in the State Park.

Despite being surrounded by tools and having some down time during the day, I was too focused on the racing to install the new sprockets at the track. At 4pm, the racing shut down for the day and we started the return trip. Michael went north but the three of us from Atlanta decided to ride back over Mt. Cheaha then pick up I-20 east for our return trip.

Rather than taking it easy I went into full “attack” mode on the curves around Mt. Cheaha at which time I started hearing strange sounds when getting hard on the throttle. I pulled over at the visitor center and discovered that the front sprocket (hidden beneath the hydraulic clutch cover) was so badly worn that the chain was skipping over the rounded off teeth. Apparently the roller spacing on the new chain didn’t match the spacing of the worn teeth on the old sprocket and basically shaved down every tooth. Uh oh.

The dead sprocket

I tightened the chain and proceeded on at a much more cautious pace but the damage was already done. By the time we got to I-20, the chain was slipping regularly and as we neared the Alabama/Georgia border, it was starting to slip more often than it would grab. Fortunately, there was a truck stop there so we pulled off and I started to disassemble the bike.

I borrowed some tools from the truck stop (their shop was closed for the day), including a long freakin’ breaker bar, so that I could swap the sprocket out in their parking lot. Fortunately, I had brought along the correct metric socket with my own tools! As with my first “Box of Shame” story, the real screw-up is that one mistake is followed other mistakes. In this case, I was working on the bike at night, in a parking lot, with borrowed tools and working faster than I should have so that I wouldn’t hold up my riding buddies any longer than necessary. As a result, I didn’t pay attention to the small lock nut which prevents the large front sprocket nut from backing off. I applied the big freakin’ breaker bar to the socket so I could remove the sprocket nut and promptly stripped the last few threads off the sprocket shaft when the lock nut was pushed off as the sprocket nut rotated. Argh!

It took about half an hour to clean up the threads on the sprocket shaft with a pocket knife before I was able to install the new sprocket (fortunately, the truck stop’s junk box contained a replacement metric bolt that would work as a temporary lock nut), tighten the chain, re-install the bodywork and get back under way. I finally got home about 10pm at night, a good two hours later than originally intended. The following week I had to buy the correct lock nut and re-cut threads on the shaft. That’s a lot of time and work which I’d have been better off spending replacing the sprockets when I did the chain in the first place.

Well, no one was hurt and the rounded off sprocket looks pretty cool in the Box of Shame.