So, I just went to take my GX eagle derailleur off my hardtail and when the bolt holding it onto the dropout came loose a couple of parts pinged off into the floor. After searching around to find these, and having a quick look online, it seems that the part that came off is the b-tension bolt plate (and horrible spiral Circlip thing) that also holds the main hanger bolt in.
A quick google search has brought up the video below showing this part being put back in but it looks like the sort of thing that may drive me mad if I start to attempt it.
Has anyone successfully managed to reassemble these parts before? Should I just get myself a glass/bottle of wine and sit down to try and get it done? Would I be better off just stabbing myself in the face for half an hour before going and ordering a new (shimano) mech and shifter (or trying to make a warranty claim for a failed part)?
Yes, I’ve swapped out the mech pivot bolt after it’s got sloppy.
Best advice I can offer is use a ball.point pen to run round the flat coil spring as you hold everything in place. Might take a couple of goes but it will work
Dont forget to get the ball point between the layers of the spring
That said, it’s the sort of job that I irrationally quite enjoy so I might rationally be excluded from giving you advice on this.😁
However,I would always advice having the beer/ wine after the repair as a reward. That always works better for me than getting bladdered during the (poorly attempted) repair.lol
Hi OP, i have fixed one using the video you link to. it was to fix a spare mech to take with me on trans provence. i ended up loaning the mech to someone diring the race and they bust the bolt again.
Anyhow long story short, the circlip and spring are not needed. i spoke to both the mavic and sram mechanics and they said that they do not affect the function of the mech, they are basically there to keep the bolt in place if you take the mech off.
Yes. SRAM mechs doing things like this is one of the reasons I minimise my use of them though!
Just watch your fingers as you need to wind it up quite a bit to get everything in place, the spring can jump out at inopportune moments. Pliers help.
I’ve done it a couple of times on Shimano road mechs too, as on the winter commute the salt can get in and stop the pivot moving so it needs occasional greasing – similar principle but the mech doesn’t self destruct.
I do them semi regularly on customers bikes, a bit fiddly the first time until you get the technique.
Allen key or t25 clamped upright in a vice holds the mech/bolt nicely. If it has a wave washer then a clamp/molegrips can be used to compress the plate to mech leaving both hands free to install the clip.
I finally got some time out from the new baby to have a go at fixing this tonight and managed to get the circlip back on on the third attempt. So, nowhere near as annoying as I thought it was going to be.
I was very glad to be able to pull a dental pick, of a similar shape to the one used in the video, out of the tool box to use as that did make the whole thing much easier.
The derailleur is back on the bike now and if it does this again in the future I may be tempted to take the advice above and just leave it off as this isn’t a job I want to get too familiar with.
