Bicycle Mechanics - Compatibility issue between shifters and cassette

Hi there.

I am new to this forum and road bikes (well after a 20 year layoff) and I have a compatibility query which I have found conflicting answers to.

Please be gentle with me :)


I purchased a bike from Ebay a year ago http://www.halfords.com/webapp/wcs/stores/servlet/product_storeId_10001_catalogId_10151_productId_272635_langId_-1_categoryId_165710#dtab
and found I would like to upgrade the Sora shifters to something like 105 or Tiagra for example as the thumb buttons are starting to get on my nerves as cant stay on the drops and change gear.

However, owning to the fact of little funds to spend on I am looking to dip in the murky world of Ebay again and buy a second hand set from Ebay. Looking on Ebay though there doesn’t seem to be much choice of 8 speed shifters available.
My question is, if I bought say a set of Shimano 9 speed shifters would they be compatible with my 8 speed cassette?

Are there any recommendations from you guys when bearing in mind price and performance?

Appreciate any help you can give.

e-bay can be a good source for bike components, but I would not buy used shifters.
Shimano 9-speed shifters can be used to shift 8-speed Shimano cassettes IF the rear derailleur is 8-speed Dura-Ace which has a unique actuation ratio.

It is possible to convert from 8-speed Shimano to 9-speed Shimano with new shifters, cassette, and chain. The old derailleurs and crankset should be OK to use. This would be the better option.

Given that the new brifters will be, by far, the most expensive part of this upgrade, it would be worthwhile to just buy a matching 9-speed cassette and chain and not have any compatibility problems. The 9-speed cassette will fit your existing 8-speed freehub and your rear derailleur will also work so no other change will be required.

Marauder9, On the cheap and doing it yourself an integrated shifter swap is the least expensive. You might be able to buy bar end shifters and brake levers more cheaply. You'll need a set of metric allen wrenches, minimum. Probably bar tape. Keep an on on e-bay and craigslist as NOS shows up now and then.

The 9S swap will require additional expense for the chain and cassette plus a spec tool to R&R the cassette and another for the chain.

Brad

Thanks for all you help guys
Will take your comments forward and keep my peepers open for some items on Ebay I think will be suitable.