Newbie question about upgrading/replacing shifters

Wibs

Hi all - first post and very pleased to be here. I'm hoping you can bear with me whilst I ask what's probably a daft question to all you experts.

After many, many years out of the saddle I've just got hold of a road bike that's about 10 or 12 years old with a Shimano RX100 8 speed groupset (double chainring). I've never had a bike with brake lever shifters before so it's all new ground for me.

If I were wanting to upgrade to a 10 speed cassette (perhaps 105, judging by a quick internet browse last night), could it be done simply by replacing the right hand shifter/brake lever and putting a 10 speed chain on it, or is it (as I suspect) far more involved than that? In other words, is the "brain" of the index system in the brake lever/shifter bit?

Any advice gratefully etc etc etc.

Cheers!

Ron

mexico

Providing the spacing of your rear triangle is wide enough (and I THINK on an 8 speed it will be), it can be done yes. However you will need: 10 speed freewheel, 10 speed rear mech, 10 speed chain, 10 speed sti shifters and probably a 10 speed freehub, although I have heard that 8, 9, and 10 speed freewheels all use the same size of freehub, but don't quote me on this.

John.T

You are right. The shifter is the brains behind it all. It is possible to get single shifters but not easy. Usually Ebay. However the latest 10sp shifters are a very different shape from RX100 so you would probably want to change them both. You would also as a minimum need a 10sp cassette and chain. The mechs and chainset will work, perhaps not as well as the correct ones but well enough.