drivetrain rebuild and other changes

As mentioned in my last post there were quite a few little changes afoot the week before Sunday’s ramble. I was trying to hold off until after the end of the year to fix everything up, but since I’ve been riding the trucker more, stuff just wears out.

I went to replace my chain at the beginning of the summer only to find that my cassette finally didn’t mesh with new chains after 5600 miles. Given the parts I had at the time I decided to put the old chain back on and run it until it started shifting poorly or skipping under load and then replace everything. I finally got my wish about 2 weeks ago after a scary commute when my chain jumped the cog in my 13/14ish gear and I thought I was going head over the bars for a second. I felt kind of bad wasting a good set of crank arms when all I needed to replace was the middle and outer rings which were the only ones that were worn. (The granny is steel and I never spent too much time there) If I knew how big of a can of worms I was opening up by trying to mesh old and new parts from different makers I would have just sprung for a whole new crank and been done with it…

old ring

Looking at the old ring above carefully you can see the recessed portion for the chainring nut. Pay attention to the depth and then compare to the new one.

new ring

I ordered replacement rings ordered from riv. They said it didn’t matter if it was Vuelta or Sugino or Blackspire, or whoever, but I assure you it does. I went to bolt it in place, and the first time around the chainring bolts spun and spun no matter how hard I tried to tighten them. Once I took everything apart, broke out the vernier calipers, and started inspecting stuff the cursing commenced. The new outer ring was too recessed for a standard double chainring bolt and not recessed enough for a single bolt. It wasn’t long before I was devising a way to manufacture bolts which were relatively close to the new 0.210″ (5.334 mm) standard size my ring combination required.

nut on a bolt in the vice

grinding bolt

The orange electrical tape is a .210″ thick slice I hand-trimmed and wrapped around for a cutting guide. I ground it down to the edge, filed clean and dressed the inside threads a bit for good measure. Worked ok to get the ring bolts to clamp tight. Then it was on to derailleur adjustments…

The other thing riv mentioned on their site was that you absolutely don’t need ramps or pins on the rings to get it to shift properly. This isn’t my first time at the rodeo with front derailleur adjustments, so I was a bit frustrated when I got to the point where I couldn’t find ANY happy medium on the outer limit screw where it would shift into the big ring without allowing the chain to rail right over onto the crank arm. I tried shifting on the workstand and shifting while pedaling on the trainer to no avail. Hours wasted messing with it and by Friday night there was talk of visiting bike shops and finding a rental to sub for Sunday. 8:15 on a Friday evening and I decided to put it away for a while. There are times when I curse the day that I chose to handle mechanical work myself and this was one of them. Saturday morning I went downstairs for a fresh start and had good enough luck to deem it safe for road testing by afternoon. Worst came to worst I’d just ride the whole ride in my middle ring which would be a spinny pain, but manageable. Bike rode great once I got it outside. So well in fact that I thought it was trying to lure me out into the middle of nowhere so it could explode and leave me stranded. Natural shifting when not under load (when a bike is on the trainer it nearly ALWAYS has at least a slight load which is something new I learned this week) was acceptable and I only railed the chain over the big ring once. Back at home I made a few small tweaks and it was ready to go for Sunday. I cleaned and re-lubed the chain with Boeshield spray lubricant. I’m giving it a try to see if it holds up better than the Pro-Link I’ve been using. Some of my chain wear might have been from my cleaning/lubing practices that I’m overhauling as well. Guess I won’t know if it really does work better since I’m not keeping track of all my miles any more…

Last but not least, bag configurations. I’ve had a mini Acorn saddle bag for ages. When I hit 202 lbs a month or so ago, (my 90% of the way there weight goal) I brought myself one of their Tubular Bags so I could have a matching front/back set. My original plan was to have the mini saddle bag on the back and a handlebar bag on the front but I really don’t like the way the Trucker falls into a turn with a load high on the bars. I even noticed negative handling from the Topeak bag I’ve been sporting for the past year or so let alone something bigger. Well the configuration which works beautifully is the small Acorn bag up front with my camera and a little food. The bag hangs down and naturally tucks under the stem bringing the weight back as far and low as possible for a bar bag.

Everything else goes out back in the tubular bag which is just big enough to fit it all. Clothing changes and other light stuff can go in my hydration pack which I don’t mind wearing at all in the winter. The only hack I had to do with the bag was cut a sliver of material from an old belt and sew it to the back of the bag because it didn’t have a blinky loop on the back for some reason.

Oh, and the light mount up front survived alpha and beta testing so I treated it to a coat of primer and paint.

The long and the short of it was the bike worked great and rode better on Sunday than it has for months. Life is good.

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