Help, Help, Help.
My stumpy has developed a horrible habit of slipping gears and I'm unable to select the Innermost cog. Have stripped my rear mech (xtr), cleaned it as per Part tools advice, still no joy, have adjusted the H L screws, countless times and still no joy. The teeth on the cassette (Sram 7.0) are good, no hooking, and the chain(Sram PC951)is brand spanking new.
I'm now at a loss as to what to try next, can anyone shed any light, all suggestions welcome,
take the chain of and line it up visually. Click your way through the gears sans chain! Go from there.
If you undo the cable and undo both the h and l screws - can you push the mech into the innermost sproket? if you can then the problem is with the cable/shifter
new cable? full outers? either of these might help if the cable is getting excessive wear
Are the jocky wheels ok? Has the hanger taken a knock? Is that a new chain on the old cassette? (that can make em slip but it should still select the largest cog)
Gavinski has it right for checking by pushing it into place.
Undo cable, wind out H and L screws, get mate to pedal upturned bike, try and slide mech into all gears. replace cable, if it doesn't work after this its the shifter.
check. bent hanger.
and alwasy do your indexing in the 2nd cog.
switch to the little cog, take off the cable tension with the barrel adjuster, and undo the allen bolt for the cable.
Adjust the L-H screws so that the chain runs nicley on the smallest cog. Then pull with ur hand the cable,
and refix the allen bolt. Now shift up, and adjust the barrel adjuster for the tension until it shifts up. Voila, the others should be good.
sell it all on classified as lightly used 😆
No, no, no. Its the church of single speed trying to convert you.
Is there any space between the upper pulley and largest sprocket? There should be a 5mm gap, you may need to adjust the tension setting.
Thanks All,
Will work through your suggestions, when the wee ones are tucked up in bed, and let you know how it goes.
Mmmmm singlespeed is an option, no more fettling with H and L screws, indexing and the such 🙂 like
Your cassette is probably more worn than you think which won't be helping.
I'm with mr Barnes on this one, new chain on old cassette is asking for problems.
Thanks for all you advice, have decided to take a tea break, as its not happening. Will gather the troops again, tomorrow for another assault.
The problem was there with the old matched chain, just thought I would try and eliminate one area at a time 😆
Bent mech hanger?
if the mech hanger is bent no amount of tinkering will achieve a perfect result, so check that first. I bent mine and yet it looked fine till I checked alignment.
next: release cable at the rear mech and check the chain drops into the smallest gear. adjust limit screw, tighten up cable then manually push mech to largest cog and adjust limit screw. then muck about for a min or two to get the indexing right.
If its still ghost shifting it could be a worn rear cassette or the cable outer could be too tight and when the suspension compresses it tightens the cable and causes your mech to shift.
Have you shortened the new chain too much ?
Wrap it around the largest rear & largest front cogs, add a link & that's how long it should be.
Three cheers for STWers,
A big thank you to all that suggested what to do to solve my 'little' problem. The mech's shifting, just like its new out of the box, and fathomed out that the slipping is the chain rings on the front, so its off to LBS for a new set.
There is absolutely no black art, it is simple engineering; adjusting things "countless times" seems to be the problem. Adjust once so it's RIGHT, then leave alone. Repeat for all settings according to manufacturer's instructions, PARK, Sheldon etc. When you find a setting that cannot be got right; you've found your problem.