Bike front derailleur limit screw problem, stripped?
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Bike front derailleur limit screw problem, stripped?
Hello,
I can't tighten/screw past a certain point in the high limit screw on my front derailleur.
Once I hit the point, it just spins.
If I push hard with the screwdriver, the screw gets pushed in but it springs out again and doesn't catch.
Is the part it screws into shot?
Can I do anything other than replace the derailleur?
Keep in mind, if the cost of whatever I need to fix exceeds that of a basic derailler, might as well just replace.
I can't tighten/screw past a certain point in the high limit screw on my front derailleur.
Once I hit the point, it just spins.
If I push hard with the screwdriver, the screw gets pushed in but it springs out again and doesn't catch.
Is the part it screws into shot?
Can I do anything other than replace the derailleur?
Keep in mind, if the cost of whatever I need to fix exceeds that of a basic derailler, might as well just replace.
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If you can maneuver a tap into the space, I would guess you can just tap it and use the matching-sized screw as a limit screw. This is a rear mech with a stripped limit hole that I tapped to M5. (Notice the black screw under the "Suntour."). I found it at the coop for $2.50 and overhauled it -- it was otherwise in great shape.
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I guess, if I've never seen a need to re-tap anything and hence have never investigated what tools are required to do so, it means I'm re tarded and shouldn't attempt to fix this myself.
AnkleWork and dedhed - get lost!
I'm here to learn.
..
AnkleWork and dedhed - get lost!
I'm here to learn.
..
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You just got "lost" on my ignore list.
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Bill,
Just for snicks and giggles can anyone new to being a mechanic explain to me what a trunion is, or even a trunion bearing?
"Turbo Encabulator" the original. I'll be waiting for replies.... Smiles, MH
Just for snicks and giggles can anyone new to being a mechanic explain to me what a trunion is, or even a trunion bearing?
"Turbo Encabulator" the original. I'll be waiting for replies.... Smiles, MH
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I suspect the cost of a tap would approach that of a replacement derailleur, and a new derailleur would carry no risk of inadvertent damage.
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On the other I try to stay away from Mopars in general
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Dedhed,
On the GM models they were called spurbing bearings, but served the same purpose. Smiles, MH
On the GM models they were called spurbing bearings, but served the same purpose. Smiles, MH
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Part of learning is knowing you limits or when something is not cost effective.
Personally, depending on what the bike and/or derailleur were, I'd stuff some fine steel wool in the hole, crank the screw back in, and call it good.
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update: OK I should not be surpised that the contraption has such a large presence on the ole "dub.dub.dub".
Last edited by Prowler; 03-10-20 at 05:53 AM.
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I may just live with it since the bike is older and has other potential issues. Just means have to be very careful not getting the cable tension too tight.
As is, I had to replace the front gear shifter and have been having a lot of problems getting the indexing right since the old one was not indexed to the gear and fine adjustments were possible with the old one.
I've read it's not good for the chain to open the link - any truth to that.
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If the screw threads in part way and then slips, the screw is the problem. The threads are damaged in the area of the screw where it starts to slip.
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The master link will look slightly different from the other links. Ideally, a "master link pliers" is used to open the link, but a needle nose pliers, carefully applied, is often sufficient.
N.B. the width of the master link must match that of the chain to which it is attached, so a chain for a 9-sprocket cluster will use a "9-speed" master link.
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I can only tell you what is wrong, based on the symptoms you described. If the low limit doesn't need to go in as far, maybe swap it with the high limit screw. Otherwise, take the screw to a bike shop and see if they have one in their junk parts box.
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^^^^^ Those screws are quite standard. I was missing a limit screw on a Shimano FD, probably a Deore, on one of my MTB. Happened to be on that bike when I spotted a cheap big-box store bike in a dumpster, with a bottom-of-the-line Shimano FD. Whipped out my Leatherman, unscrewed one of the limit screws, dabbed a little grease on the threads from my seatpost, and was back in business.
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If the screw itself is ok, you may be able to get the screw to grab properly by inserting a piece or two of monofilament fishing line into the hole, then screwing in the screw. Fiddle around with the mono size (8lb, 10lb, 12lb) you get the drift. A bike shop may have an extra screw or a broken RD in parts.