New Chain and Cassette - Chain slipping under moderate load

Beansontoast

Hi Everyone,

I have just replaced my chain and cassette.

I also had a go at re-indexing.

On the stand, the changes are smooth.

On the road, the chain slips under only a moderate amount of load which makes the ride impossible.

New chain - KMC x9.93
New cassette Shimano CS-M770 11-34.

Considering indexing is "i think" ok, can someone advise on what else may be causing this?

Would chain length have anything to do with this?
Would the chainrings have anything to do with it?

Both the chain and cassette were around 5 years old.

Specialised Pitch Pro 2009.

I have a feeling this is gonna be a schoolboy error but I'm not sure what exactly.

Thanks ......

Chunkers1980

Might need new rings too. Check the chain length is correct. Chain routed correctly. Mech on correctly. Stiff links. Jockey wheels not worn. Cassette is tight?

FishFish

And quite possibly the cables need cleaning and oiling

buddy_club

At that age and if they had done alot of miles then it will almost certainly be the chainrings causing you problems.
Also change cables and outers and maybe even jockey wheels.

Beansontoast

Righto .... I'll go pickup some chainrings.

Would anyone know or recommend what brand I should be replacing with?

Looking at the online specs, I see this as the original parts -

CHAINRINGS22S/32S/44A 4mm thick outer, 4 bolt 104/64mm

No mention of brand. This is on my specialized 09 (possibly 08).

Dirtydog11

[url=http://www.bikeradar.com/forums/viewtopic.php?p=19768990#p19768990]Beansontoast[/url] wrote:

Righto .... I'll go pickup some chainrings.

Would anyone know or recommend what brand I should be replacing with?

Looking at the online specs, I see this as the original parts -

CHAINRINGS22S/32S/44A 4mm thick outer, 4 bolt 104/64mm

No mention of brand. This is on my specialized 09 (possibly 08).

Probably Shimano OEM, would go with Shimano Deore rings, generally 44t will outlast 32 and 22t so it's quite possible you will only need to replace those two.

Beansontoast

Nice .... and maybe a bonus on price possibly too, compared to some others I'd stumbled across.

Ok. Next question ....slightly confused on the bolt selection.

http://www.chainreactioncycles.com/au/en/shimano-deore-fcm590-9-speed-triple-chainrings/rp-prod83370


Where my spec says " 4 bolt 104/64mm" the above is asking me to choose. Can I basically choose either?

Beansontoast

And can you mix the two?

I see CRC have all three in stock, but different bolt circles.

Would that matter?

swod1

[url=http://www.bikeradar.com/forums/viewtopic.php?p=19769007#p19769007]Beansontoast[/url] wrote:

And can you mix the two?

I see CRC have all three in stock, but different bolt circles.

Would that matter?

Well 64bcd is usually the granny ring size and 104bcd is the outer/middle rings but just measure that to be sure.

Should be fine as long as you get chain rings the right bcd size for your chainset and for multi ring setups so they have the shift ramps on

Beansontoast

Ok everyone,

Thanks for all the advice.

I have now replaced the chainrings, all three of them, and problem solved!.

I might have a look at some of the other suggestions when I have more time, but chainrings were definitely the culprit.

Right then .... time for a spin.