Stuck front derailleur bolt - what options do I have?

[mcfee03]

Hi,

I recently bought a used 2011 Giant XTC 29er.

It apparently hadn't been ridden much in the last 6 months. The front derailleur (Deore) kept rubbing, and adjusting the high/low screws didn't help. The derailleur cable itself was loose.

Needing to tighten the derailleur cable, I used a lot of force (with allen key) to loosen the bolt. Regardless of which way I turn the key now, it neither tightens or loosens.

The edges are not blunt on the bolt. The nut (on the otherside) isn't moving. It all looks new (no wear/rust).

I hope I don't have to replace my derailleur over this.

Does anyone have any suggestions?


https://imgur.com/a/kuPIG

[m@]

So the bolt turns, but doesn't loosen? Sounds like stripped threads if so; the bad news is it's a replacement job; but the good news is front derailleurs are cheap. You might pick one up second-hand from someone who's converted to 1x...

[mcfee03]

So the bolt turns, but doesn't loosen?

Exactly.

Oh that's a huge shame. There's nothing else I can try?

My current setup has 3 cogs- what is the terminology to look out for when buying? Can I buy any model? (I noticed even SRAM are cheap- $19 for SRAM 3.0 Front Derailleur Dual Pull)

[eeksll]

you can't just buy anyone. I choose one cause it was the cheapest and I can't get it to work properly on the bike i got it for. You have to look at difference in teeth between each chainring and match that up with the specs on the derailleru.

its also possibly that most are likely to work and the one I got was the odd ball (which could have been why it was cheap)

[mick243]

if you can get the screw out, you may be able to retap the hole and either use a bigger screw, or put a helicoil in the new thread and use the old screw.


soak it with wd40 or penetrene etc and apply force from behind it whilst you try to unscrew it.


judging by the damage to the cable (assuming you didnt do that?) it looks to be that someone tried to adjust it, screwed up, overtightened the screw (partially stripping it, causing it to sieze)


but m@ is likeley right - repair via replacement is likeley the easier and cheaper and faster option.

[Duck!]

If the bolt can be extracted (try vice grips, you can pull on the bolt while turning it, and can often engage some undamaged thread) there's no need to replace the derailleur. The nut is a separate piece captive in the derailleur body, so all that's needed is a new nut & bolt. Your LBS should have some kicking around in the spares box (I do).

[mcfee03]

I did it!

Got the bolt out using an allen key, and I angled it until I felt resistance and pushed through.

A bit of science and patience.

Now Im just realligning the derailleur. Im struggling a bit- any chance it's at the wrong height or does it look right?

[Duck!]

Turn the bike up the right way & take a pic of the crank/derailleur looking square-on, then I'll be able to tell you.

You want about 1mm clearance between the lower edge of the outer derailleur plate & the tips of the tallest teeth of the big ring. When sighted from above, the outer plate should be parallel to the big ring. With the chain on the small ring & big rear sprocket, adjust the low limit screw until there is only a small gap between the chain & inner derailleur plate.

[mcfee03]

take a pic of the crank/derailleur looking square-on

Cheers for this, here's a pic-

EDIT: Oops forgot to turn it the right way up. Do I need to retake the pics?



https://imgur.com/a/x67y3" onclick="window.open(this.href);return false;

[KGB]

Looks like it needs to be higher. I can't se a 1mm gap like duck said. Without that gap, you risk the derailleur hitting the big ring as you change gears.

Not the best photo though, could be a bit of parallax error. We need to see square on to the area between the derailleur and chain ring.

[mcfee03]

Cheers, I've sorted it out. It was due to my amateur status. It didn't need to be moved.

On a separate note (and maybe worthy of a new thread) is there much point in me buying a new set of shifters? I've got Alvio shifters, and Deore front and rear Derailleurs. Everything works well. Will shifting be that much smoother if I buy some SRAM X7's? I noticed they're quite cheap on eBay (for new)...Unless they're fakes?

[mitchy_]

Cheers, I've sorted it out. It was due to my amateur status. It didn't need to be moved.

On a separate note (and maybe worthy of a new thread) is there much point in me buying a new set of shifters? I've got Alvio shifters, and Deore front and rear Derailleurs. Everything works well. Will shifting be that much smoother if I buy some SRAM X7's? I noticed they're quite cheap on eBay (for new)...Unless they're fakes?

you'll certainly notice a difference if you buy Sram shifters... as the rear won't be compatible with your shimano derailleur.

[mcfee03]

as the rear won't be compatible with your shimano derailleur.

Ah, so SRAM shifters would mean I'd have to change all my derailleurs? This is all new to me

[mitchy_]

as the rear won't be compatible with your shimano derailleur.

Ah, so SRAM shifters would mean I'd have to change all my derailleurs? This is all new to me

yep. the front derailleur can play nicely, but the rear as a rule of thumb does not.

you can change up to SLX or XT shifters however. unless there is something wrong with yours, or they dont feel nice enough, i'd stick with them though.

[mcfee03]

unless there is something wrong with yours, or they dont feel nice enough, i'd stick with them though.

Absolutely nothing wrong, I think it was a silly idea.

On another topic- can someone suggest an inexpensive bleed kit for my Alvio (M445) disc brakes? Or even just the mineral oil.

My rear brake isn't giving me much feedback (feels 'spongy'). So I did a bleed which failed, and I spilled the $30 bottle of mineral oil everywhere. Not sure where I went wrong- I had the resoviour elevated to get air bubbles bout, and flicked the cabled to more any air bubbles

[Duck!]

Check the brake caliper is aligned with the disc properly (and that the the disc isn't bent while you're at it). If the pads don't contact the disc flat, they'll squeeze & bend the disc to suit the caliper angle, giving a spongy feel.

You can make a bleed kit to suit most Shimano brakes* very cheaply. Pick up two 20mL plastic syringes (without needles) from a chemist (or even some hardwarey shops) & some 3mm PVC tube from Bunnings (a 5-metre roll is only $a few, but overkill seeing as you only need 30 mm or so). Best to get the right oil though; the wrong stuff will damage the seals in the brakes.

*Those that require the reservoir cap to be removed need two syringes. Later models, which just have a plug in the reservoir cap to remove only need one syringe and are best bled with the proper Shimano screw-in cup. I've tried improvised substitutes, but they're messy.

[mcfee03]

Mine does require a reservoir cap to be removed. Did it without one and yes- was messy. Will the best bleed necessarily use all of the bleed fluid in a 30ml syringe? I ask because I've done a couple bleeds tonight (with the tiny bit if remaining mineral oil) and it's still spongy.

Disc is straight and alignment seems correct.

My bike shop charges $30 and the bottles lid doesnt screw on (ie how i lost it all) so hoping not to go back. Can someone suggest a cheap online place to grab it?

[Duck!]

Two syringe job. Generally only need to half-fill one syringe, but if you're really unsure about the quality of the previous bleed, go for 3/4 full. Before attaching to the caliper, seal the tip of the short bit of hose with a finger & pull back on the plunger to release any gas dissolved in the oil. Maintain vacuum pressure until all the tiny bubbles have merged into one, then release vacuum & remove air, pushing oil up the hose to the tip.

Rotate brake lever up so reservoir is level, and remove cap. Connect oil-filled syringe to bleed nipple on caliper, then open. Allow any bubbles to escape into syringe, pulling just a bit of suction to ensure there are none in the caliper. Inject oil into caliper, and with your other syringe, draw off fluid from the reservoir as it fills. Keep this up until no more bubbles enter the reservoir. Close caliper bleed nipple & remove syringe. Fill reservoir and gently replace seal & cap; have a rag handy to catch the excess, because you will lose a bit of fluid. Clean with metho.

[m@]

Good result! Make sure you apply grease to the threads of the new bolt when you reinstall it, so you don't have the same problem next time you need to replace the cable

@Duck! I didn't realise the FD cable pinch bolt screwed into a captive nut; though thinking about it, the FD is about the only thing that's sat untouched on my Anthem since I bought it. I could've sworn the Deore 9-speed FD on my hardtail just screws straight into the pivot arm though...

Mine does require a reservoir cap to be removed. Did it without one and yes- was messy. Will the best bleed necessarily use all of the bleed fluid in a 30ml syringe? I ask because I've done a couple bleeds tonight (with the tiny bit if remaining mineral oil) and it's still spongy.

Disc is straight and alignment seems correct.

My bike shop charges $30 and the bottles lid doesnt screw on (ie how i lost it all) so hoping not to go back. Can someone suggest a cheap online place to grab it?

I think I paid less than that for a 500ml bottle from c r c! If you're in Melbourne you're more'n welcome to some - the rear on my Anthem is a little spongey and with different hose routing on the replacement frame (and lowered stem) both hoses could use a trim... so I can also show you through the process if you like.

A workstand helps to get the bike on the right angle to tap out any air bubbles along the hose... found getting rid of all the air from the rear is quite a process, but worth it for that direct feel.

On a separate note (and maybe worthy of a new thread) is there much point in me buying a new set of shifters? I've got Alvio shifters, and Deore front and rear Derailleurs. Everything works well. Will shifting be that much smoother if I buy some SRAM X7's? I noticed they're quite cheap on eBay (for new)...Unless they're fakes?

SRAM trigger shifters are quite cheap - for a reason IMO. Grip Shift OTOH is excellent (but only available toward the higher end, and will require a matching rear derailleur). I'll likely be selling my XT shifters and RD at some point...

[mitchy_]

unless there is something wrong with yours, or they dont feel nice enough, i'd stick with them though.

Absolutely nothing wrong, I think it was a silly idea.

not necessarily... some of the low end shifters feel rubbish. if yours feel ok though, money is best spent elsewhere or even saved!

[mcfee03]

Good result! Make sure you apply grease to the threads of the new bolt when you reinstall it, so you don't have the same problem next time you need to replace the cable

I think I paid less than that for a 500ml bottle from c r c! If you're in Melbourne you're more'n welcome to some - the rear on my Anthem is a little spongey and with different hose routing on the replacement frame (and lowered stem) both hoses could use a trim... so I can also show you through the process if you like.

A workstand helps to get the bike on the right angle to tap out any air bubbles along the hose... found getting rid of all the air from the rear is quite a process, but worth it for that direct feel.

Cheers for the offer, but I'm in Sydney. Would be great because I'm very keen to learn how to properly look after my bike. I greased the new bolt, and the gears are all aligned correctly. I think SRAM was an impulse thought- I don't really have any need for it.

Also @Duck! I made sure there were no bubbles/gas in the syringe. And I followed all your other instructions too. But still no luck. The disc is straight, the pads aren't worn ([http://imgur.com/tDsgHLb)

I did two bleeds, flicking the tubes, and I had a decent 'make shift' stand which elevated the reservoir well. Still it's very spongy.

Could it be that I didn't have enough mineral oil in the Syringe in the first place?