MWF FEED
8th February 2022, 08:40 PM
Ever wondered why the heads on the Philips head screws on your Jap bike are usually stuffed, simple, they are not Philips heads. Cross head screws come in a variety of types, but the two giving the most trouble are Philips head screws and JIS screw heads. There are a plethora of articles on the Web explaining the difference, so I won't bother, but use the wrong screwdriver on a cross screw head and you'll more than likely strip the heads.
The TX's screw heads were all stuffed, both inside and out. I replaced all the external screws with stainless hex heads. There's not too many inside the engine, just the pressure plate screws and a bracket for the cam chain fixed to the upper crankcase between the cylinders, these I didn't worry about as they looked OK, but the pressure plate screws were absolutely stuffed.
The pressure plate screws are stepped, an 8mm, or thereabouts, section directly beneath the head with no thread, followed by a M6 x 1 threaded section. To fix them, I cut the threaded section off, then mounted them in the lathe, faced the heads until flat then drilled through with a 6mm drill. After that it was just a matter of inserting an Allen head of the right length through the hole and screwing into place.
You can buy Allen head clutch plate screws, but why buy when you can make with what is to hand, and then there's the price, $50 for six screws.
Attached Images
https://metalworkforums.com/images/attach/jpg.gif pressure plate screw breakdon 2.jpg (https://metalworkforums.com/attachment.php?attachmentid=396691&d=1644311227) (66.7 KB)
https://metalworkforums.com/images/attach/jpg.gif pressure plate screw comparo.jpg (https://metalworkforums.com/attachment.php?attachmentid=396692&d=1644311240) (66.7 KB)
https://metalworkforums.com/images/attach/jpg.gif pressure plate screws old and new fitted.jpg (https://metalworkforums.com/attachment.php?attachmentid=396693&d=1644311254) (64.9 KB)
Read the full thread at metalworkforums.com... (https://metalworkforums.com/showthread.php?t=207731&goto=newpost)
The TX's screw heads were all stuffed, both inside and out. I replaced all the external screws with stainless hex heads. There's not too many inside the engine, just the pressure plate screws and a bracket for the cam chain fixed to the upper crankcase between the cylinders, these I didn't worry about as they looked OK, but the pressure plate screws were absolutely stuffed.
The pressure plate screws are stepped, an 8mm, or thereabouts, section directly beneath the head with no thread, followed by a M6 x 1 threaded section. To fix them, I cut the threaded section off, then mounted them in the lathe, faced the heads until flat then drilled through with a 6mm drill. After that it was just a matter of inserting an Allen head of the right length through the hole and screwing into place.
You can buy Allen head clutch plate screws, but why buy when you can make with what is to hand, and then there's the price, $50 for six screws.
Attached Images
https://metalworkforums.com/images/attach/jpg.gif pressure plate screw breakdon 2.jpg (https://metalworkforums.com/attachment.php?attachmentid=396691&d=1644311227) (66.7 KB)
https://metalworkforums.com/images/attach/jpg.gif pressure plate screw comparo.jpg (https://metalworkforums.com/attachment.php?attachmentid=396692&d=1644311240) (66.7 KB)
https://metalworkforums.com/images/attach/jpg.gif pressure plate screws old and new fitted.jpg (https://metalworkforums.com/attachment.php?attachmentid=396693&d=1644311254) (64.9 KB)
Read the full thread at metalworkforums.com... (https://metalworkforums.com/showthread.php?t=207731&goto=newpost)