Follow on from previous post Cassette & Chainrings

[jps71]

Hi Guys
This is a follow on from my previous post with another question.

I got a new cassette to replace rthe worn one same make Sram & same number of teeth on the cogs.
I got the old cassette off with out to much hassle.
The old cassette consisted of cogs fastened together & 2 loose cogs.
The new cassette has 7 cogs fastened together & 1 loose cog.
Upon fitting the cogs I find there is approx a 5mm gap between the 7 cogs and the 8th cog meaning I can move the 7 up & down the splines.
It didn't come with any spacers & there wasn't any on the old cassette (apart from the ones between cogs)
Is it simply a case of getting spacers off the old cassette and putting them behind the 7 cogs until there is no gap between 7 & 8.?
Hope some one can help.
Cheers Jim

 

[lpretro1]

Sounds like you need a spacer behind the cassette - so spacer on, fit cassette

 

[TissoT]

As said above you need a starter spacer .

 

[jps71]

Thanks for the replies guys.

I take it a starter spacer is different to a spacer between the gears.
I put one of the spacers off the old cassette on behind the cassette & it closed up the gap.
It has though thrown all the gears to cock I had to reindex them as the chain jumped off & it is now missing gears.
Cheers Jim

 

[lpretro1]

You now need to reset the limit screws on the derailleur - that's all. Or if you don't know what you are doing take it to your lbs

 

[jps71]

You now need to reset the limit screws on the derailleur - that's all. Or if you don't know what you are doing take it to your lbs

Hi

Thanks for the reply.
I have already reset the limit screws due to the chain jumping off.
The problem I have is that it is nowe completely missing gears ie jumping from 8 - 6 or being in 1 when should be in 2.
when shifting down stays in 1 when changing to 2 then jumping to 3 when selecting 3 etc.
it was changing gear okish when I first changed the cassette before realising there was the 5mm gap but now the gap has been closed I cant get it right.
Cheers Jim

 

[TissoT]

Thanks for the replies guys.

I take it a starter spacer is different to a spacer between the gears.
I put one of the spacers off the old cassette on behind the cassette & it closed up the gap.
It has though thrown all the gears to cock I had to reindex them as the chain jumped off & it is now missing gears.
Cheers Jim

Yes that's Right the starter spacer will be a little thicker 3/4mm (round washer)... The cog spacers look completely different and thinner , If you are unsure it may be worth while taking it to your LBS if your gearing has been thrown out of sink

 

[jps71]

I have now found out what the problem this is actually a 9 speed cassette with the 8th gear cog missing.
The ratio of teeth on a 8 speed is 8th gear 11 teeth & 7 the gear 12 teeth.
On a 9 speed the ratio is 9th gear 11 teeth 8th gear 12 teeth 7th gear 14 teeth.
This has 8th gear 11 teeth & 7th gear 14 teeth.
Bloody ebay sellers.

 

[boydj]

The problem is with the spacing between the cogs, which will be smaller on a nine-speed cassette than it is on an 8-speed and will not match the movement on an 8-speed shifter.

 

[jps71]

All sorted now & everything working ok (touch wood)
Thanks for all the advice