08-10-2017, 08:07 AM
I have brought an old Giant GSR200 (early 90's I would guess), as a hack to use to commute to the station in the morning, and leaved locked all day. I am happy with the condition of the bike, and for a tenner it was a bargin!
The only issue I have is that being so old it has Shimano SIS thumb shifters (the ones on the top of the bars). I would really like to change these as I find them awkward to use, so I started to search around on google for help but now I am confused more (I am very mechanically minded, but have little experience with bikes!).
So far I have established that I have a 6spd rear cassette(?) which is not the cartridge type but the screw on freewheel type and a Shimano SIS rear derailleur. It looks like to change to either gripshift or rapidfire (preferred) will warrent a change to a 7sp at the rear (unless anyone knows of a source of 6sp shifters?). I am happy to do this, but this is where I get lost.
What do I need to know/consider and how to I go about working out if this is possible. Can i change the 6sp for a 7sp cassette/freewheel assembly? Is there a better way to get around this problem?
I'm happy to spend a bit on this (>£50), partly for the experience of making the changes and learning through doing!
Any help would be greatly appreciated!!!
The only issue I have is that being so old it has Shimano SIS thumb shifters (the ones on the top of the bars). I would really like to change these as I find them awkward to use, so I started to search around on google for help but now I am confused more (I am very mechanically minded, but have little experience with bikes!).
So far I have established that I have a 6spd rear cassette(?) which is not the cartridge type but the screw on freewheel type and a Shimano SIS rear derailleur. It looks like to change to either gripshift or rapidfire (preferred) will warrent a change to a 7sp at the rear (unless anyone knows of a source of 6sp shifters?). I am happy to do this, but this is where I get lost.
What do I need to know/consider and how to I go about working out if this is possible. Can i change the 6sp for a 7sp cassette/freewheel assembly? Is there a better way to get around this problem?
I'm happy to spend a bit on this (>£50), partly for the experience of making the changes and learning through doing!
Any help would be greatly appreciated!!!
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