Slipping gears - New build Shimano / SRAM

beardwithabike

Hi everyone,

Picked up a Specialized frameset recently and built it up with a mishmash of Shimano and SRAM parts. I plan to upgrade the full groupset next March when I have some cash, but for now I was trying to do things cheap / with stuff I had in the spares box.

On the stand, the bike works fine, gears shift well, 8 speed set up, no issues. But as soon as I jump on it and apply some power the chain / gears slip and skip making it unrideable. I am pretty sure one or more of the Shimano / SRAM parts are not working well together - but I'm not bike-clever enough to know what.

Any thoughts? If I can change one or two things to get it working then you'll be a lifesaver. Like I say, can't afford a new groupset right now.

Parts:
SRAM Apex Crankset
Newish Stronglight CT2 11/10 speed 53t and 39t (double) chain rings
Brand new Shimano HG40 6-8 speed chain
8 speed SRAM rear cassette
Shimano Claris front mech double
Shimano Sora rear mech 8 speed
Shimano 105 8 speed levers
Brand new gear cabling

sungod

was the cassette new or used? a new chain will skip on a worn cassette

k-dog

Yep, that's the only thing that makes sense - the rest should work together if nothing is worn.

beardwithabike

I'll give it a go. Makes sense to me as it was an old cassette. Thanks!

sungod

if you've got an old worn chain (8/9/10 speed, doesn't matter), try that, if it's worn enough to match the cassette wear it may run without skipping

saves getting another 8 speed cassette given that you're planning on changing groupset

beardwithabike

Just swapped the worn cassette with a spare that has a lower range but it's solved the issue! Thanks guys. I'l have to get some bigger legs to power up the hills but at least it won't skip!