Stripped master brake cylinder screws, What to do?

[tk2stroke]

I recently purchased my son a used 07 CR85 and have made it a project bike build. After rebuilding most of the entire bike, I came across these two highly stripped out master cylinder screws. I am stumped, how can I get these suckers out without ruining the reservoir. Like many ham fisted bike owners, these suckers are in very tight.

[CrankItUPMotor]

I recently purchased my son a used 07 CR85 and have made it a project bike build. After rebuilding most of the entire bike, I came across these two highly stripped out master cylinder screws. I am stumped, how can I get these suckers out without ruining the reservoir. Like many ham fisted bike owners, these suckers are in very tight.

I usually clean out all the dirt really well, then take the best phillips screw driver I own (#2 Snap-On) and a hammer. Then while twisting, tap the top of the screw driver with the hammer and they usually back out without damage. Replace the screws once removed of course.

[Hammy.]

drill the tops off the screws...

or use a Dremel with a thin cut off wheel to cut a groove in the screws so you can use a flathead to remove.

[sjvmtb]

Had some in similar shape to yours and got them out with these. Got mine at the local hardware store.

https://www.amazon.ca/Ontel-SpeedOut-Damaged-Screw-Extractor/dp/B00IRL3WP4?th=1&psc=1&source=googleshopping&locale=en-CA&tag=googcana-20&ref=pd_sl_2wfu1pr5x6_e

 

 

[CDNSXV]

Or just go buy a set of Easy Out screw removers?  Cause that is what they are designed for.

 

[Yzmaster]

Buy some different screwdrivers with a wider star and get some old inner tube and see if you can fill the gap enough to remove the screws (if they aren’t dead tight)

[MentalGuru]

1 hour ago, CrankItUPMotor said:

I usually clean out all the dirt really well, then take the best phillips screw driver I own (#2 Snap-On) and a hammer. Then while twisting, tap the top of the screw driver with the hammer and they usually back out without damage. Replace the screws once removed of course.

 

They aren't Phillips screws, trying to remove them with a Phillips screwdriver is what causes them to strip. 

Honda like the other Japanese manufactures use JIS screws(Japanese Industry Standard).  You need to use JIS bits and if they are really tight use a hammer type impact driver it will do the trick.

I'm still amazed that more rider don't know this...

 

Here is the difference.

 

This is the type of impact driver you need.

 

 

[S.O.A.N.Z]

Tiny little pin dot punch - light hammer - light taps at an angle on the side - always works

 

 

[tk2stroke]

11 hours ago, sjvmtb said:

Had some in similar shape to yours and got them out with these. Got mine at the local hardware store.

https://www.amazon.ca/Ontel-SpeedOut-Damaged-Screw-Extractor/dp/B00IRL3WP4?th=1&psc=1&source=googleshopping&locale=en-CA&tag=googcana-20&ref=pd_sl_2wfu1pr5x6_e

 

 

I have a set of these, just havent used them before. I suppose this will be my go to attempt.

[tk2stroke]

10 hours ago, MentalGuru said:

They aren't Phillips screws, trying to remove them with a Phillips screwdriver is what causes them to strip. 

Honda like the other Japanese manufactures use JIS screws(Japanese Industry Standard).  You need to use JIS bits and if they are really tight use a hammer type impact driver it will do the trick.

I'm still amazed that more rider don't know this...

 

Here is the difference.

 

This is the type of impact driver you need.

 

 

Never mind more riders, after 47 years I've never even heard of the JIS standard. At least I learned something new today, now I can shut off for the rest of the day.

[Dodging_roost]

5 hours ago, tk2stroke said:

Never mind more riders, after 47 years I've never even heard of the JIS standard. At least I learned something new today, now I can shut off for the rest of the day.

Here, Here.... I have always used a Philips head screwdriver as well, and usually they seem to work... shutting off now..

[unswitched]

I like using reverse twist drills, left hand drills. Often they spin out before the head comes off.

[mbrick]

KTM uses torx screws for these... amazing.  No more stripping.  Or, use A JIS bit and clean the dirt out first and that usually helps.

[jguarfn28]

I got a JIS impact screwdriver off Amazon but of course haven't needed it since it arrived. It was like $14 with postage from Nippon.

[Gflo]

Buy some valve grinding compound.  Fill the stripped area with the compound, and insert the proper screwdriver.  The compound will fill in the areas that are missing.  Works like a charm.  A small jar of compound is cheap, and you can get it at your local auto parts store.  Learned this trick about 40 years ago, and hasn’t failed me yet.

[Madmax75]

18 hours ago, tk2stroke said:

I recently purchased my son a used 07 CR85 and have made it a project bike build. After rebuilding most of the entire bike, I came across these two highly stripped out master cylinder screws. I am stumped, how can I get these suckers out without ruining the reservoir. Like many ham fisted bike owners, these suckers are in very tight.

Look up time seats kit they work really well

[JonWR250f]

Sometimes when you round a screw off you can lay a wide rubber band over the screw and jam your screwdriver in while pushing into the rubber band and turn, sometimes that gives you just enough grip to get the screw undone

[TheFamilyGuy]

I drilled the heads off, just enough to get ride of the head itself. Then remove the cap and there will be enough screw sticking out to attach vide grips too. The screws drills really easily, so don’t drill any further then you have too

[bosarge22]

19 hours ago, MentalGuru said:

They aren't Phillips screws, trying to remove them with a Phillips screwdriver is what causes them to strip. 

Honda like the other Japanese manufactures use JIS screws(Japanese Industry Standard).  You need to use JIS bits and if they are really tight use a hammer type impact driver it will do the trick.

I'm still amazed that more rider don't know this...

 

Here is the difference.

 

This is the type of impact driver you need.

 

 

THIS!

 There has been after market parts for all sorts of JIS screw replacements, usually with Allen bolts. Mostly from the use of Phillip on JIS screws. Even in JIS you have to pay attention to pitch too.  Carbs are probably #1. 

[MentalGuru]

1 minute ago, bosarge22 said:

THIS!

 There has been after market parts for all sorts of JIS screw replacements, usually with Allen bolts. Mostly from the use of Phillip on JIS screws. Even in JIS you have to pay attention to pitch too.  Carbs are probably #1. 

I remember my '70s bikes which used JIS screws to hold everything together.  Case covers and all sorts of parts.  A hammer type impact driver was a must.  I use it to break loose JIS screws on carbs and such to this day.  Stereo components and other electrical products made in Japan use JIS screws too.

If you look close at the comparison pic I posted you'll see a Philips screwdriver can be modified with a file or careful bench grinding to turn it into a JIS head.