I’m trying to get an M810 9spd mech to index properly, all the bits are new incl cableing etc but if I tention the cable enough to index up the block then the chain tries to climb back into lowest gear (34 teeth) when I drop down to the second biggest. If I slacken the cable so this does not happen then it won’t index from high gear (11 teeth)to the next few gears. This one realy has me thinking, we’re running a 2×9 setup with a stinger and the chain is correct in length, have I missed something realy obvious or is it a more complicated issue?
Any help would be great.
Thanks

Have you set it to all mountain mode by putting the little mode converter plate on, you need this for it to work on 11-32 & 11-34 cassettes.

Yep the plate is on mate, don’t know what else it could be do ya?

Take the cable out of the sleeves. Take the end caps off the sleeves, and then trim the wires back with some decent cutters.
Quite often on long cable runs the wires that stiffen the sleeves work their way our and then bunch up.

Regular problem with convoluted cable runs, if you’re using new outers, are they good quality or cheap’n’cheerful? I’d recommend Shimano SP41 as it comes pre-lubed with a thin and slippery grease, and a pair pf SP4 sealed end caps to keep it that way. May also be worth checking you’ve not over-clamped the cables and constricted them.

Thanks for the help but it turned out to be a bent 34 ring on the cassette. It was going out by about 0.25 mm and just lipping the chain. I hate straighteneing drive cogs of any type but my mate had just brought this HG80 less than 50 miles ago. JD

All wires were new IE ss jagwire inners, alloy ferrules and PTFE lined 4mm jagwire outers (smoother than a very smooth thing from the planet smooooth) and cut with propper cutters, cleanly.

all the bits are new

So it wasn’t all new…

Yep, you right, it wasn’t all completely new but it was not worn in yet so technically you are right, there are, however no prizes on offer but give yourself a pat on the back and certainly feel slightly superior to me mate, i’ll be more exact in my posts on this singletrack forum from now on, please don’t be me any more Sir, please oh please……. 😳