JIS Cross Head Screw Drivers

[peterbaron]

I've had a set of JIS screwdrivers in my toolbox for years. I read an article recently about JIS, that said that Japanese vehicles are increasingly using standard Phillips screws and that JIS is phasing out, but can't remember where I read it.

My friend is working on a 1933 Rolls in his shop. He had to track down a set of Whitworth wrenches to work on it.

Because I'm also into vintage British bikes I have a full set of Whitworth wrenches and sockets - as well as SAE and metric.
All needs are covered

Because I'm also into vintage British bikes I have a full set of Whitworth wrenches and sockets - as well as SAE and metric.
All needs are covered
Nice to know about this handy/all needs Halifax garage...during my trip to Newfoundland this summer???....just in case

Because I'm also into vintage British bikes I have a full set of Whitworth wrenches and sockets - as well as SAE and metric.
All needs are covered
Nice to know about this handy/all needs Halifax garage...during my trip to Newfoundland this summer???....just in case
Notice the decal at the top of the display

Because I'm also into vintage British bikes I have a full set of Whitworth wrenches and sockets - as well as SAE and metric.
All needs are covered
Nice to know about this handy/all needs Halifax garage...during my trip to Newfoundland this summer???....just in case
Notice the decal at the top of the display


Ya, ya noticed: no tools loaned...

What a nice vintage moto shop, all wrenches labelled, so even blind mechanic feels comfortable there...
No, no, nothing big, just need to inspect plain bearing clearances, by using pltstguauge and rlets instalment.....
Hey Atlantic habitant; m in sc, Lord Popgun and few others...stop wrenching at home while there is this vintage shop with Rolls Royce+ quality up north....

Good show Rocky, I like it very much and booking my appointment for mid July, I will cover all expenses at your local Tim Hortons or better as per your desire ........

[Cormanus]

I think Honda phased out JIS screws 20 years ago or more, although there may be some electrical sub-assemblies that have them, and on carbs. I remember back in the points and condensor days, JIS screws holding them on had a different thread pitch, so lots of points plates got stripped as a result.

Countersunk screw heads like the 4mm ones on master cylinder caps are hard to loosen because they have a lot of surface contact area (and friction) under the head, and are prone to corrosion. A cross (+) is used in that application so that the 4mm threads aren't easily snapped off, as if it would be with a hex bolt or hex socket head. When removing master cylinder covers, I usually just grab the hand impact driver and give it a light tap to break it free, never fails.

Are you saying the screw heads on the CB1100 are not JIS? I’m confused now.

[pekingduck]

I think Honda phased out JIS screws 20 years ago or more, although there may be some electrical sub-assemblies that have them, and on carbs. I remember back in the points and condensor days, JIS screws holding them on had a different thread pitch, so lots of points plates got stripped as a result.

Countersunk screw heads like the 4mm ones on master cylinder caps are hard to loosen because they have a lot of surface contact area (and friction) under the head, and are prone to corrosion. A cross (+) is used in that application so that the 4mm threads aren't easily snapped off, as if it would be with a hex bolt or hex socket head. When removing master cylinder covers, I usually just grab the hand impact driver and give it a light tap to break it free, never fails.

Are you saying the screw heads on the CB1100 are not JIS? I’m confused now.

Are you saying the screw heads on the CB1100 are not JIS? I’m confused now.
I think Honda phased out JIS-head screws 20 years ago or more ...

The distinction between JIS and Phillips screw heads hardly exists any more in practice. I don't think there is any Honda reference to them anymore as JIS-head, just refers to them as Phillips or simply (+).

A good JIS screwdriver will fit fine in a Phillips head. A good Phillips will work fine in JIS screws. For the most part, only carb bowls and tops use JIS, maybe some sourced electrical components.

Honda bikes and cars have been made throughout the world, including Europe, UK, South America, India, Mexico, US, and of course Asia, and there needed to be a common standard, as hardware may be sourced locally. (Hornet 599 and 919s were made in Italy.)

Too many cheap, wrong-sized, too pointy (Reed-Prince), worn out screwdrivers, and previously-rounded slots often are blamed for stripped screw heads.

[Cormanus]

Thanks.

[2017EX_imp]

Unfortunately there is no way to know ( that I can find ) whether or not Honda discontinued using JIS cross heads, and if in fact they were discontinued, when that change took place. I can pass on some observations. I was fortunate to have been gifted a couple of Phillips Snap On screw drivers some time ago, by a friend who worked for Snap On. Anyway, a #2 Snap On fits the master cylinder cap screws with a hint of wobble, whereas a #2 Vessel JIS Cross Head screw driver fits those screws rock solid.

I think over the years, we have all seen + heads in various locations on a motorcycle, particularly master cylinder cap screws, that were unbelievably booger-ed up. Granted, many shade tree would-be mechanics and owners use cheap tools, and/or the wrong size tools. For me, here is one of the most important things I ran across while researching the subject, copied and pasted from the article, and something I knew from experience back in the day,

"Most people and companies outside of Japan have absolutely no idea what they are. With the similarity in appearance to the Frearson and the Phillips the screws are often damaged in removing and installing with the wrong tools. JIS tends not to camout like Philips. The JIS driver can be used on Phillips quite easily but not reciprically."

That last sentence is the kicker. I can use a JIS screw driver on a Phillips without consequence, but using a Phillips on a JIS can ( not always ) result in damage. Bottom line, you are good to go with a JIS Cross Headscrew driver when it is unknown if you are dealing with a Phillips or a JIS head.

[peterbaron]