Chain wear - cassette wear

[joggingbob]

Apologies up front I am a noob to this so my questions and statements perhaps belong in the beginners section.

I checked my chain recently using a steel ruler and checking for wear along 12 links and the 'stretch' was a tad over 1/16" so i thought it needed replacing but nothing untoward. I duly purchased a chain and replaced it and the test ride revealed it was jumping a lot, (more than once per pedal revolution). As such I assume that the cassette is worn and I left it too late . There does appear to be some worn edges on the common gears on the cassette. I reckon I have cycled circa 4 to 4.5k miles on the chain, (the original chain). I must admit maintenance has been restricted to cleaning and oiling the chain.

So my questions:-

1) Is my assumption correct i.e. worn cassette?, (I have checked the new chain for stiff links and they seem to all move fine).
2) Can I continue to ride with the old chain whilst a new cassette is bought and find someone to fit it? (circa 75 -100 miles per week)
3) Alternatively if the cassette is worn should I leave all as in until the old chain starts jumping? (assume this would also wear the jockey wheels and front chainring).

 

[fossyant]

Worn cassette....

I'd order a new one, and just manage on the old chain until it arrives.

Not worth doing option 3 really.

 

[joggingbob]

Thanks fossyant, cassette duly ordered, (managed to find one on ebay at a good price).

 

[joggingbob]

Well the cassette has arrived and I would like to have a go and changing the cassette myself. I appreciate that I need to buy a chain whip and cassette removal lock nut, (will any SRAM tool remover also work on SRAM?). I have had a look at the bicycle tutor video and it appears straightforward but I have a few questions that someone can answer for me:-
1) I assume I need to remove the skewere to get to the cassette. Is this just a simple case of unscrewing the skewer retaining nut and then pulling the complete skewer out? (and the reverse to refit?)
2) The cassette arrived as a block bar the smallest two rings and the two smallest rings do no have separate spacers. Do they require spacers if yes then I assume I will find out when I take the old one off and then re-use them if needed.
3) The cassette is to be tightened to 40Nm - do people use a torque wrench or just tighten up till it feels tight?

In case it helps it is a SRAM cassette on a Trek MTB.

Thanks for your patience with my beginners questions.

 

[mr Mag00]

1) yes
2)no spacers required fit as is, should only fit one way. there are grooves on the cassette hub and asingle wider groove to match internal grooves of cassette.
3) i tightened as hard as i can and never had a problem obviously do not blow a blood vessel trying to overtighten.

hope that helps

 

[joggingbob]

mr Mag00 thanks for the quick reply. Do you know if Shimanao cassette removal tools will also fit SRAM cassettes? (I had heard that the two were compatable but not for Campy). I am about to buy a tool but it only states Shimano not SRAM.