Bicycle Mechanics - Upgrading gearing

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View Full Version : Upgrading gearing


jsbgraphics
06-20-08, 04:28 PM
I have an Old Sekine 10 speed that belonged to my dad and I would like to put some new derailers and brakes on it.

My question is right now it has a Shimano lark rear derailer and a thunderbird front derailer with down tube shimano fingertip shifters. Is there a current set of derailers that will work on this bike or would I also have to change the cassette and crank as well?

Second it has Shimano tourney center pull brakes. They are in pretty good shape and work OK, but I need to replace the levers. Are there current shimano levers I can use with this type of brake?

Any help would be greatly appreciated.

JB


JiveTurkey
06-20-08, 05:58 PM
What's wrong with the current derailleurs and brake levers?

jsbgraphics
06-20-08, 06:20 PM
The bike does not shift very well. I haven't had the time to work on tuning them up, but I thought with the age that is on them it might not be a bad idea to replace them.

The brake levers have safety handles which I despise so I just wanted to get rid of those. The current levers work, I just want to get rid of the safety levers.


Jeff Wills
06-20-08, 11:00 PM
I have an Old Sekine 10 speed that belonged to my dad and I would like to put some new derailers and brakes on it.

My question is right now it has a Shimano lark rear derailer and a thunderbird front derailer with down tube shimano fingertip shifters. Is there a current set of derailers that will work on this bike or would I also have to change the cassette and crank as well?

Second it has Shimano tourney center pull brakes. They are in pretty good shape and work OK, but I need to replace the levers. Are there current shimano levers I can use with this type of brake?

Any help would be greatly appreciated.

JB

The Lark and Thunderbird derailleurs were cheap stuff for their era- I would be willing to bet that replacing them with Shimano Altus or Sora parts will work without issue. You might run into a problem with the old chain and new derailleur- chains have gotten a little narrower over the years, but an "8-speed" chain will work on the current freewheel without issue. It won't be index shifting, but I think indexing is oversold anyway.

Any current "road" brake lever will work with your centerpull brakes. Here's a good, basic set:
http://www.universalcycles.com/shopping/product_details.php?id=6623
Here's the corresponding Shimano set:
http://www.universalcycles.com/shopping/product_details.php?id=6373