I saw this on another forum, and went to do a bit more exploring. It seems that the reason so many of us are having difficulty with our carb screws is because they aren't Phillips at all!

Is this the right time to mention JIS-spec screws and drivers?

In theory, all Japanese motorcycles use JIS-spec screws, rather than
SAE or generic metric screws. JIS-spec cross-head screws are
(apparently) marked with a single dot or an "x". So, what's the
difference between JIS-spec and the rest? In most cases, not much,
but if you've ever wondered why it is so easy to strip out the head on
a Honda cross-head screw (aka "Phillips", or more properly but still
wrong, "Japanese Phillips"), it is likely because you are using a
Phillips screwdriver on a JIS-spec screw...

As any astute reader of Wikipedia knows*, Phillips-head screws (and
drivers) were specifically designed to "cam out" when too much torque
was applied in either direction. That's bad enough (and one of the
reasons why "Pozidrive" screws and screwdrivers were invented), but
this tendency is exacerbated when the wrong driver is used and/or the
fastener in question is a bit stuck. JIS-spec screw heads are
shallower, which means that Phillips screwdrivers won't fully seat in
them (unless ground down a bit). In addition, the JIS-spec screw head
features a completely parallel cross, while the Phillips screwdriver
has a taper to its cross-point.

Most cross-head screws found on modern Hondas are button-head, which
can usually be removed with a Phillips driver, but I've found some
countersunk JIS-spec screws (albeit only on my NR rear wheel...) into
which no Phillips or Pozidrive screwdriver I've tried will even fit.
So, I've had to research JIS drivers and have found that they are
available (the RC helicopter boys seem too have the same problems with
JIS-spec fasteners) online if you know where to look, but that most
people and companies outside of Japan have absolutely no idea what
they are. Since I often buy stuff through Yahoo Japan Auctions, I
will probably score my set of JIS-spec drivers from there at some
point, as the ones exported into the USA don't seem to be of the
highest quality (and I have yet to find any being sold here in the
UK). Vessel and KTC seem to be the leading brands, though each have
drivers of varying quality. And I think there are only two common
sizes, unlike Phillips and Pozidrive, which are commonly available in
0, 1 and 2. HTH.

(* My way of stating that what follows sounds right but could be
complete bullshit.)

Ciao,

JZH
London, UK
www.vsource.org (http://www.vsource.org/)


On 6/3/08, Patrick Shelston wrote:
>
> The only thing I would mention is that the screws and bolts on the carbs are
> generally softer, so it is key to use good tools and the right sized screw
> drivers (snug fitting) to prevent stripping/breaking. I figured this out
> the hard way :)
from here: http://vfrworld.com/forums/vf-vfr-mailing-list/15586-re-difficult-idle-now-jis-spec-screws-drivers.html

Great info! :goodjobsign:

yes, I agree... great info. :)

as a common practice, I always push the screwdriver down into the screw head as hard as I can before I apply sideways torque to loosen any screw. If the screwdriver head fits relatively tight in the screw head, the chances of stripping it out is slim.

That and make sure the faces of the splines of your Phillips screwdriver is not chewed up. Cheap tools deform easier due to their softer temper of the steel that is used, which is why I use Craftsman hand tools with their lifetime warranty... When the wear out, take them back to the store for a brand new one.

Kelly, Second the need for good tools. Mine are Craftsman, Snap-On, and Park Tools (for the bicycles). I use torque wrenches a lot primarily because a lot of bicycle components are carbon fiber and aluminum. It looks like motorcycles are going in the same direction. Besides, I always feel better when I have a torque spec on a bolt.

Kelly, Second the need for good tools. Mine are Craftsman, Snap-On, and Park Tools (for the bicycles). I use torque wrenches a lot primarily because a lot of bicycle components are carbon fiber and aluminum. It looks like motorcycles are going in the same direction. Besides, I always feel better when I have a torque spec on a bolt.

I agree that every person who works on a bike should own and learn to use a torque wrench. I'm not saying I use it all the time, but until one gets a good "feel" for what the correct tightness is for a particular fastener, the best tool to learn what is correct is the torque wrench. There are some applications, however, that I will not use anything but a torque wrench to insure proper spec on a critical fastener.

Car wheel lugs and oil drain plugs are 2 that always see my torque wrench when it comes time to put them back on.

http://www.centralhobbies.com/Tools/jis.html

and you get a nice catalog with specialty tools included!

$17.99 + S&H

http://www.centralhobbies.com/Tools/jis.html

Thx for the link! :rad: I just ordered a set.

I saw this on another forum, and went to do a bit more exploring. It seems that the reason so many of us are having difficulty with our carb screws is because they aren't Phillips at all!


Good info :thumbup::thumbup:
http://www.centralhobbies.com/Tools/jis.html

and you get a nice catalog with specialty tools included!

$17.99 + S&H

Nice! :)

All those phillips screws on the 250R are NOT Phillips screws. Here are bits (JIS) which can be used in the MOS tool, which works great for those hard to reach screws.

http://www.ninjette.org/forums/picture.php?albumid=18&pictureid=126

those crazy japanese....

that said, I shoudl get some of those

Guys, I haven't thought this in a long time, but twenty years ago this why I always used the screw driver supplied in the tool kit to break the screws loose.

I just hope the tools are made of a stronger steel than the butter screws they use, but good point about the stock tool kit having appropriate tools for the screws used on the bike... maybe. :)

Do we know if all screws on the bike are JIS or only these on the carbs and other places?

Not sure about some of the smaller screws, but I'd think the kit should have the right type.
Many years back, the case screws were "phillips" and the only way to get them out was with the supplied tools.
We used to replace them with allens most of the time though.
I do remember drilling the heads out on a few, pulling the cases, using vise grips on the studs and then installing allen bolts.
It's probably been twenty years since they used phillips on the case bolts.
But it might pay off to check the tool kit.
I do agreed, if you are going to do much work on bikes, buy the right tools.

I do agreed, if you are going to do much work on bikes, buy the right tools.

I agree... but if only the screws with the dimple marks are JIS, which there are just a few from what I've seen, maybe one could get by with the toolkit tools in that case. Good thinking... I'll have to check that out. Beats stripping the JIS screws using an incorrect Phillips head screwdriver, which seems very easy to so with those carb screws.

lol... I had completely forgotten about replacing the case screws with allens... I used to do that with all the dirt bikes I had back then. :lol:

If you read about the design of JIS screws and the US phillips screwdriver, they both interact to MAKE the screwdriver NOT grip the screws correctly.

The screwdrivers supplied with the bike are a P.O.S. in my opinion, but I might be inserting them in the handle wrong. I think they are more trouble than they are worth.

The JIS set, with integral handles, have worked on every screw on my bike with no damage. I was even able to do the carbs with them; however, as I stated previously, I did use a phillips bit with the MOS for the 2 screws under the frame. I put lots of pressure, so the bit didn't rotate out.

On any stubborn Phillips screw I always put the bit in a 1/4 in socket on a 1/4in ratchet. It makes it easy to push down hard and put torque on the screw.

On any stubborn Phillips screw I always put the bit in a 1/4 in socket on a 1/4in ratchet. It makes it easy to push down hard and put torque on the screw.

Just for clarification, the JIS screws are not stubborn Phillips screws. Matter of fact, they are very easy to remove with a JIS screwdriver. If you research how a JIS screw is designed versus a Phillips screwdriver, it's kind of like trying to remove a one-way screw with a regular flathead screwdriver. The flathead screwdriver just walks right out without gripping the screw! The JIS screwdrivers I use haven't damaged any of the screws on my bike. There are only 2 screws with any visible damage (had to use a Phillips bit in the MOS, as mentioned above) to get them out of the carbs, in order to remove the needles. They are still very usable.

Thx for the link! :rad: I just ordered a set.

Let us know how they work out Alex...

Got 'em. Put 'em in the tool chest. Haven't had an opportunity to use 'em yet. :)

It is really amazing that Sears-Craftsman has not heard of JIS Screws. I am going to check out NAPA, Mac Tools, Makita, and Snap-On. I would like to get a set that will work with my impact driver. It is strange that the official Kawasaki Shop Manual makes no mention of JIS screws. A bit set that can also be used with a racheting screw driver or 1/4" socket ratchet would offer the most versatility.

I am going to check out NAPA, Mac Tools, Makita, and Snap-On. I would like to get a set that will work with my impact driver. A bit set that can also be used with a racheting screw driver or 1/4" socket ratchet would offer the most versatility.

Alex A B,

Did you miss post # 9 above? Just what you're looking for! :thumbup:

Alex A B,

Did you miss post # 9 above? Just what you're looking for! :thumbup:

I think that I will probably put in an order with them. Have you seen the screwdrivers called "Posidrive"? They claim to be the same as JIS. Snap-On , Mac Tools, SK Tools, Milwaukee, and Makita make them. I will check them out further and try to find a whole set ranging from 0 to #4 in both the long and short bit.

This thread brings back memories...

First, Hi Torque/One way screws in the aerospace industry(similar to pic)

...those things are a beast to remove/install.


Second, Who remembers King Of Queens where Arthur wanted to invent the "A" head screw, to make a million dolars?

This whole thing blows me away. We finally got away from Whitworth, were promised to be all Metric, and are ultimately stuck with SAE, Metric, and now JIS. Sure would be nice if there was some standard. We went through the 4 Channel Stereo era with three incompatible systems, then we went through the Beta vs VHS war, Now DVD vs Blue Ray. It`s really a pain in the a$$.

JIS substitute???

http://www.ninjette.org/forums/showpost.php?p=117762&postcount=20

Back in GA, my friend assured me that he could remove the screws from the front brake reservoir using a certain screw driver (can't recall if it were one of mine or one from the bike's tool kit). I told him that I didn't do it myself because I could tell that it was going to slip and I was looking for the right screwdriver. This prompted him to try it himself to prove it to me. The screw immediately chewed up and the driver spun in place despite all the weight he was putting into it. Now I have a nice shiny bit of silver staring at me wherever I go! Idiot. I colored it black again with a Sharpie but that didn't last long.

Buy the JIS set I linked to in a previous post. One of the drivers will remove that screw for you. :thumbup:

See attached.

Buy the JIS set I linked to in a previous post. One of the drivers will remove that screw for you. :thumbup:

See attached.

Thanks, yeah, I know. I just wanted to tell the story. :thumbup:

http://www.rjrcooltools.com/jis.cfm

so, the drywall bits won't work?

All those phillips screws on the 250R are NOT Phillips screws. Here are bits (JIS) which can be used in the MOS tool, which works great for those hard to reach screws.

I just ordered the 3 piece set. Cost is NOW $10, but shipping is still FREE.

I had two tamper proof bit sets. Just so happen's they have some philip type bits that fit the bike perfect :thumbup:

Kelly, Second the need for good tools. Mine are Craftsman, Snap-On, and Park Tools (for the bicycles). I use torque wrenches a lot primarily because a lot of bicycle components are carbon fiber and aluminum. It looks like motorcycles are going in the same direction. Besides, I always feel better when I have a torque spec on a bolt.

+1 for the Park tools. I ride a couple different road bikes, a hybrid, and a track bike. Park tools are the only tools I use on the bicycles, especially since one is worth more than the 250!

i just bought the 3 pieace bit set and also a long #2 screwdriver, and i also picked up some #4 brass washers last nite :thumbup: i have some questions about what happens next but there seems to be a ton of simming threads which one should i post to?