[Matojo]

So today I was trying to drain the carburator float bowl and stripp the little phillip screw, went to bigger screwdriver stripped a little more, try to catch the head with a flat one and nosing. So I guess now is time to try a screw extractor and see.Its anyone here have the same problem with this particular screw? Losen this screw is the only way to drain the float bowl other than take the carb apart?



Any information would get a big hugg!!!

 

[jbfla]

...is anyone here have the same problem with this particular screw?...

Yes, all the stock screws on the carb are easily stripped. Unfortunately, the carb drain screw is the only one that cannot be replaced with a socket head screw.



Try the screw extractor.



I put a bit of anti-seize on the threads of the drain screw to make it easier to remove.

...Loosen this screw is the only way to drain the float bowl other than take the carb apart? ...

Yes, but it's not that hard to remove the bowl, 4 screws... that are also easily stripped. Replace them with steel socket head screws... then be careful not to over tighten them or you may strip the aluminum threads on the carb.

jb

 

[cdsdave]

I stripped it trying to drain the carb. It was in way too tight for any screwdriver to loosen. Since I ride it pretty much year round other than a handful of weeks in the winter months I don't see any need to drain the carb. In fact I finally got to ride the last few days after putting the bike away for most of a cold and snowy December.



Me out on one of my trails today.

 

[ZXtasy]

Well well, I had the same problem. Drilled it out...or tried with 2 diff. size left hand bits. Finally asked the Yamaha mech...he said leave it plugged as long as it does not leak. If taking the bike down for more than a few months, just take off the bowl..easy as shown by others. Can also run the bowl dry when you shut her down.

 

[Matojo]

Yes, all the stock screws on the carb are easily stripped. Unfortunately, the carb drain screw is the only one that cannot be replaced with a socket head screw.



Try the screw extractor.



I put a bit of anti-seize on the threads of the drain screw to make it easier to remove.







Yes, but it's not that hard to remove the bowl, 4 screws... that are also easily stripped. Replace them with steel socket head screws... then be careful not to over tighten them or you may strip the aluminum threads on the carb.

jb

Thanks JBfla , Im going to try an extractor first, and try the four little screws that hold the bowl if not...

Thanks again man!!!

 

[Matojo]

Well well, I had the same problem. Drilled it out...or tried with 2 diff. size left hand bits. Finally asked the Yamaha mech...he said leave it plugged as long as it does not leak. If taking the bike down for more than a few months, just take off the bowl..easy as shown by others. Can also run the bowl dry when you shut her down.

Thats a good idea, guess I can ride a little trail near by like ones a week and around town to keep the fluids flowing.

Thanks Zombie!!

 

[Matojo]

I stripped it trying to drain the carb. It was in way too tight for any screwdriver to loosen. Since I ride it pretty much year round other than a handful of weeks in the winter months I don't see any need to drain the carb. In fact I finally got to ride the last few days after putting the bike away for most of a cold and snowy December.



Me out on one of my trails today.

Yes, CDSDavid, that baby was tied in there like a "Tick in a bull" Like I was telling "Zombie" thinking about keeping on ride to keep the flow going.

Nice play ground you got there, it look like youre having fun!!!

Thanks and glad to see Im not alone in this!!!

 

[CaptD]

I stripped my drain screw out back in 2007. Didn't have my glasses on, grabbed a #2 philips screwdriver and turned the screw counter clockwise and stripped it right away. Managed to get it out along with some crap that was hanging out in the bottom of the float bowl. Ordered/bought a new one at the dealer and took it to the mechanic at work. He looked at it and dug out his screwdriver kit and after a few match ups gave me the bit to use to put the new drain screw back in the float bowl. It was not a #2 screw head. The bit set that I bought says its a "Bits for Torq Set size is 6 mm. And that's Torq not Torx. I drain it often being careful to reinsert gently and just snug. I carry this screwdriver bit with me when out riding off road cause if I ever ended up drowning the motor (water crossing) I would drain the carb (and perform a few other tasks) before restarting the motor. Capt D.

 

[peruano]

Hey Folks, Didn't I read somewhere that Japanese fasteners are not standard Phillips heads, but instead have a slightly different configuration in which the end of the drivers is flatter, not so pointed as the typical Phillips driver. The implication would be that for extremely tight bolts, the head of the screwdriver is not engaging totally making it easier to strip. I'll check to see where I read this, but it could be we need a better source for the tools we use to do these touchy fasteners. Correct me if I'm wrong. Tom

 

[Matojo]

Hey Folks, Didn't I read somewhere that Japanese fasteners are not standard Phillips heads, but instead have a slightly different configuration in which the end of the drivers is flatter, not so pointed as the typical Phillips driver. The implication would be that for extremely tight bolts, the head of the screwdriver is not engaging totally making it easier to strip. I'll check to see where I read this, but it could be we need a better source for the tools we use to do these touchy fasteners. Correct me if I'm wrong. Tom

Peruano, this screw in the float bowl looks like phillip to me but maybe isnt standard one. I wait to see if you find were you read this.

thanks Tom

 

[Matojo]

I stripped my drain screw out back in 2007. Didn't have my glasses on, grabbed a #2 philips screwdriver and turned the screw counter clockwise and stripped it right away. Managed to get it out along with some crap that was hanging out in the bottom of the float bowl. Ordered/bought a new one at the dealer and took it to the mechanic at work. He looked at it and dug out his screwdriver kit and after a few match ups gave me the bit to use to put the new drain screw back in the float bowl. It was not a #2 screw head. The bit set that I bought says its a "Bits for Torq Set size is 6 mm. And that's Torq not Torx. I drain it often being careful to reinsert gently and just snug. I carry this screwdriver bit with me when out riding off road cause if I ever ended up drowning the motor (water crossing) I would drain the carb (and perform a few other tasks) before restarting the motor. Capt D.

Capt, do you driiled out? or do you use an extractor?

thanks

 

[peruano]

Troops, I may be raising a red herring here, but its worth consideration. The Japanese use (used) Japanese Industrial Screws (and screwdrivers to match them). A JIS looks like a Phillips head screw but has a shallower depth. The appropriate screwdriver has a less pointed profile and a blunter end and hence goes firmly into the cross shaped slot and engages the full shoulder of the JIS instead of some part of the middle of the cavity. I first learned of the difference in my brief encounter with older Yamaha xs cycles. The manuals and mechanics for these bike did recommend getting JIS drivers or modifying to the extent possible Phillips drivers. Supposedly a JIS can be identified by a dot on one side of the screw. I just made a quick circle around my TW and could not find an appropriate screw to check (easily that is). The following was copied from one google link that I found. Just do a search for Japanese Industrial Screwdrivers and you will find much info. Hopefully someone in the know will tell us if the distinction still applies to our TWs. Something to think about and perhaps save us some frustration.

BTW - I realize and info on the web documents that many times the Phillips will work on JIS, but at other times (i.e. something is tight, varnished in place, or not easy to get to, the Phillips driver will goober the JIS head and cuss words will result.



Edit: At least one reference suggested that the screws on Mikuni carbs were JIS (not Phillips) and several suggested that Honda uses JIS (not Phillips). Since our bikes have been in production a long time they are likely to have some or all JIS fasteners even if some newer production might have obfuscated the difference between Phillips and JIS. Tom



When a Phillips is not a Phillips!

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by arcticpenguin

step 10JIS - Japanese Industrial Standard

Often improperly referred to as Japanese Phillips. Commonly found in Japanese equipment. JIS looks much like a Phillips screw (and even more similar to Frearson), but is designed not to cam out and will, therefore, be damaged by a Phillips screwdriver if it is too tight. Heads are usually identifiable by a single raised dot to one side of the cross slot. JIS B 1012:1985 screw standard is throughout the Asia market and Japanese imports. The driver has a 57 degree point with a flat tip, parallel wings.





Advantages and Disadvantages of JIS



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. Drivers are not easily available in North America, try your local RC Airplane hobby shop. Most RC Helicopters use JIS screws to mount the propeller. JIS-spec cross-head screws are generally marked with a single raised dot or an "X". JIS always fit Phillip fasteners, but because of slight design differences, Phillips drivers may not fit JIS fasteners. (unless the tip is ground down a bit).

JIS - Japanese Industrial Standard

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130 jis ink.jpg131 jis bit.jpg132 jis bits 2.jpg133 jis bits.jpg134 jis vs phillips.jpg

 

[jbfla]

Tom,



I believe you have solved the mystery of the TW's stripped carb screws!

I looked at the stock carb bowl screws that I removed, and they have a single dot on the outer edge of the head (on my 2005 TW).



And after a quick search, JIS screw dirver sets are available.



They are mostly avalable through hobby shops.

Here's one that turned up, that explains the fit:



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



However, since those JIS screwdrivers don't seem to be a common item in most people's toolbox, IMO, it would be a good idea to replace them when possible.



jb

 

[peruano]

JB, I too checked the screws visible on my carb. I have a 2002 and indeed all visible screws had the identifying dimple on the screw head. I also took what looked like an appropriate sized Phillips screwdriver and placed it into the head and could see space on either side which would allow the driver to rock off center, slip, and damage the screw slots. I do have one reversible driver that has a blunter head which would undoubtedly work better, but I'm going to see about getting a JIS set soon. They are available at many hobby stores and at *yes* Harbor Freight.

I also saw a note that someone's DR 650 had JIS fasteners so you in particular should invest. Tom

 

[jbfla]

... I also saw a note that someone's DR 650 had JIS fasteners so you in particular should invest. Tom

Thanks. Looks like a trip to the local HF is in order.



I can't believe that after all these years foolin' around with motorcycles, autos, and boats that I didn't know about the JIS standard.



jb

 

[Matojo]

Peruano I think you hit the nail in this one man!!! Yes this screw looks a little weird to me but I was still thinking was a regular phillip head. Yes this head is much more shaloow than most phillips I have seen.

I think it would be a good Idea to put a warning to the noobies to come along with this bikes!!!. Having say that, I now in the quest for one of this JIS screwdrider!!

Eh, thanks man!! youve been very heplfull!!!

 

[slowpoke]

i work at h depot in the hardware and tool dept and i know there are three TYPES of philips bits we carry NOT the size (1 2 3 ) that one would assume.



- A POINTY ONE FOR DRYWALL

- A STANDARD ONE FOR HOME USE

- A BLUNT POINT FOR DECKING SCREWS



I wonder if you can use the decking bits or what the heck grind the point on a standard one.



just a thought. have a nice day! cheers.

 

[CaptD]

Capt, do you driiled out? or do you use an extractor?

thanks

I used a small straight blade screwdriver to get it loose. Prolly just got lucky.

 

[CaptD]

Thanks Tom for all your work/research. JB let us know where/what set or model of JIS screwdrivers you bought and if you think that they are of decent quality. Capt D.

 

[qwerty]

Deck bits work on big JIS screws quite well. I've yet to find a deck bit small enough for the carb bowl screws.



Back in the '70s I visited Japan and came home with a set of T-handle JIS screwdrivers. I still replace potmetal OEM screws with stainless allens at the earliest opportunity.