Screw for Brake Master Cylinder Super Tight and Head is Rounding Off...Suggestions?

[Ski_rush]

I got my Apollo put back together. In the pics, you'll see the new Tusk handlebar and ProTaper grips I installed. I wish I had the foresight to have ordered a new throttle since I think the stock one is pretty silly in the way it's made, but it will work for now.

I'm in the process of checking the bike over. I do want to check the front brake fluid and possibly change it to DOT 4. One screw on that top cover of the front brake master cylinder came out without a problem. I went to loosen the second screw and it's super tight. I put most of my weight on the screw driver (i.e, a lot) and tried turning it again and it started stripping/rounding off the head of the screw. I stopped before it got bad, but if I had kept going, I would have rounded out the Phillips head on the screw head.

Any suggestions on removing that screw without destroying it or the brake cylinder? I would like to check the fluid before I ride it again.


Thanks,
ski

[Megadan]

Use the largest JIS Screw driver you can fit and hope for the best. Otherwise, a dremel cutting wheel and a slot is about the only option after drilling off the head. Using standard phillips head drivers = rounded out JIS screws.

If you don't have JIS screwdrivers, get a set. There is a decent affordable set on Amazon. I use the 2 largest sizes in that kit the most, and bought 2 sets to have one for an on the road tool kit. https://www.amazon.com/Hozan-JIS-4-JIS-Screwdriver-3rd/dp/B00A7WAHTU/ref=asc_df_B00A7WAHTU/?tag=hyprod-20&linkCode=df0&hvadid=309811990469&hvpos=1o1&hvnetw=g&hvrand=14670365675380368313&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9024572&hvtargid=pla-503880026860&th=1

[elkhunter338]

Impact driver is a good tool to have. Cordless impact gun with best fitting philips bit might do.

[Ski_rush]

Impact driver is a good tool to have. Cordless impact gun with best fitting philips bit might do.

Good idea. My father-in-law has a small cordless impact driver. I just need to find a good bit. I didn’t realize there was a Japanese standard in screwdriver size...something new I learned today.

[OneLeggedRider]

I've had luck with grinding off about 1mm of the Phillips tip, seems to seat better in a screw that's trying to round out.

[Megadan]

Good idea. My father-in-law has a small cordless impact driver. I just need to find a good bit. I didn’t realize there was a Japanese standard in screwdriver size...something new I learned today.

Most of the screws on these chinese bikes, and obviously Japanese bikes are JIS heads and not Phillips. JIS slotting is different (steeper) than a phillips head, so when a standard phillips is used, it only engages a portion of said slotting, and usually results in rounded heads. This is especially true of the cheddar cheese quality metal found on the fasteners on Chinese bikes.

The Impact gun would be something I would personally avoid. It might work, or it might round that screw out all the way in a big hurry. An actual impact driver (link) https://www.amazon.com/TEKTON-2905-8-Inch-Manual-7-Piece/dp/B000NPPATS/ref=asc_df_B000NPPATS/?tag=hyprod-20&linkCode=df0&hvadid=312003160272&hvpos=1o1&hvnetw=g&hvrand=8197299448158977006&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9024572&hvtargid=pla-420785539586&psc=1 is what I would use. You strike the end with a hammer, and in doing so you drive the bit into the screw while the driver also turns the bit a little. This is a GREAT tool to have, especially when working on old hardware or dealing with partially stripped stuff. You can get one at almost every auto parts or hardware store.

[wedooit]

Hey ski, the throttle on my new bms is cheezy, as well s yours, did you get a chance research a good replacement?.

[pete]

The tool to use is called a impact driver….



..

[JerryHawk250]

The impact drive like Dan has linked with the JIS bits. :tup:

[Ski_rush]

Hey ski, the throttle on my new bms is cheezy, as well s yours, did you get a chance research a good replacement?.

Hey, yes I did find a replacement. I will order and install this eventually. There was another guy with an Apollo deluxe who also installed this and said it fit perfectly.

Here is the Link (https://www.ebay.com/itm/7-8-22mm-CNC-Aluminum-Motorcycle-Dirt-Bike-Twister-Throttle-Grip-Cable-Assembly/283102526426?var=583507657488)

[david3921]

Soldering iron. Get an iron hot and set it on the screw. The is like heating it with a torch but safer. Not sure how long to leave it on but you are looking to get the screw warm enough to break the bond that's keeping it tight.

[Ski_rush]

+1 for Dan’s suggestion to get a JIS screwdriver. I was skeptical and thought a screwdriver couldn’t make that big of a difference. Boy, was I wrong and I’m glad I was. I bought this:

https://www.amazon.com/dp/B000TG8OTY?ref=ppx_pop_mob_ap_share

I only had to apply half the pressure to turn the screwdriver and sure enough, it turned the screw without damaging the head in the least bit.

If you don’t have this screwdriver, buy one and hide it from your wife and kids.

[Megadan]

+1 for Dan’s suggestion to get a JIS screwdriver. I was skeptical and thought a screwdriver couldn’t make that big of a difference. Boy, was I wrong and I’m glad I was. I bought this:

https://www.amazon.com/dp/B000TG8OTY?ref=ppx_pop_mob_ap_share

I only had to apply half the pressure to turn the screwdriver and sure enough, it turned the screw without damaging the head in the least bit.

If you don’t have this screwdriver, buy one and hide it from your wife and kids.

I generally speak from hard earned wisdom lol. Glad you got it free.