Shimano EF51 shifter screws

viraj

Member
Hello Members,

I was trying to change the front shifter cable however, I am unable to open the shifter housing as the screws that hold the top has lost thread as attached. what options do I have?

BIke: Trek 7.2 Hybrid
Shifter: Shimano EF51

Actions taken so far:
I did apply 3-in-one Oil hoping that this would help in unscrewing the stubborn screws.
Tried using a rubber band to assist with grip

Appreciate any pointers
 

Attachments

Location
Loch side.
Those screws are not Philips, as you would assume, but JIS, which requires a special screwdriver or, some luck and skill with a Philips screwdriver.

You need a Grabbit and battery drill with a reverse function. Then, new screws, which are available. Also buy a JIS screwdriver, the most convenient source for that is ParkTool.

It is also worth noting that oils, sprays and potions NEVER make stuck screws unstuck. It is a waste of time.
 

Pale Rider

Legendary Member
JIS - Japanese Industrial Standard - are hydraulic fittings which won't be on a cable actuated system.

Not sure what these screws are, there are a number of 'internal star' fixings, such as Torx.

I've had some success in similar circumstances with a small cross-bladed or flat bladed screwdriver - one I used last time came out of a Christmas cracker.

These fixings look well chewed, so some sort of extractor is probably your only option.
 
Location
Loch side.
JIS - Japanese Industrial Standard - are hydraulic fittings which won't be on a cable actuated system.

Not sure what these screws are, there are a number of 'internal star' fixings, such as Torx.

I've had some success in similar circumstances with a small cross-bladed or flat bladed screwdriver - one I used last time came out of a Christmas cracker.

These fixings look well chewed, so some sort of extractor is probably your only option.
No, JIS is the Japanese version of DIN. It applies to all Japanese industries, perhaps even to hydraulic fittings, I don't know about those.

Those knackered screws there definitely JIS version of Philips. Those are also on the brake calipers for adjusting dual-pivot pad position and on Shimano derailers. Although you can get away with a Philips on most of them, the small ones such as those on the shifter caps are unforgiving.

IIRC modern Shimano brake caliper balance screws are luckily torx.

https://www.parktool.com/product/derailleur-screwdriver-dsd-2
 
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viraj

Member
Those screws are not Philips, as you would assume, but JIS, which requires a special screwdriver or, some luck and skill with a Philips screwdriver.

You need a Grabbit and battery drill with a reverse function. Then, new screws, which are available. Also buy a JIS screwdriver, the most convenient source for that is ParkTool.

It is also worth noting that oils, sprays and potions NEVER make stuck screws unstuck. It is a waste of time.
Thank you Yellow Saddle. I learnt something new. looks like the other option may be to buy a new set of EF51 brake and shifters and replace the whole.
 
Location
Loch side.

wonderloaf

Über Member
Re the JIS screwheads, I believe these are also used on the front & rear derailleurs. I've always found it difficult to get a proper engagement when adjusting the high/low limit screws, usually used a flat blade but even this isn't ideal as it would sometimes slip sideways as I was eyeballing the chain line.
Anyhoo, as an experiment bought a cheap Pozi #1 driver from Wilkos and flatted the end off until a good positive engagement was obtained, slippage is now thing of the past. The driver I modded was as below:
https://www.wilko.com/en-uk/wilko-functional-screwdriver-pozi-1-x-100mm/p/0343450
At only a quid probably the best value tool in my armoury, now has special place next to the cassette removal tool, BB tool and torque wrench.
 
Location
Loch side.
Re the JIS screwheads, I believe these are also used on the front & rear derailleurs. I've always found it difficult to get a proper engagement when adjusting the high/low limit screws, usually used a flat blade but even this isn't ideal as it would sometimes slip sideways as I was eyeballing the chain line.
Anyhoo, as an experiment bought a cheap Pozi #1 driver from Wilkos and flatted the end off until a good positive engagement was obtained, slippage is now thing of the past. The driver I modded was as below:
https://www.wilko.com/en-uk/wilko-functional-screwdriver-pozi-1-x-100mm/p/0343450
At only a quid probably the best value tool in my armoury, now has special place next to the cassette removal tool, BB tool and torque wrench.
I love it when someone actually understands the problem.

I'll give your solution a try. Thanks.
 
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viraj

Member
Thanks, Everyone for your Input. I just went ahead and ordered a new pair of the shifter-EF51 and replaced the whole set. Primary reason being the lack of adequate tools along with most bike shops here in Sydney are pretty expensive.
 
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