screw size for alternator cover

R

Russdog

XS650 Enthusiast
Messages
32
Reaction score
5
Points
8
Location
Baltimore, MD
Hey Guys,
Does anybody know the screw size for the alternator cover. Both of mine were rusted in so I had to cut em out of there.

thanks,
Russ
 
Do you mean the long screws that hold the alternator to the motor block or the smaller short screws that hold the round cover that says "Yamaha" on it to the main left side cover? Both are just standard metric fasteners and may be available right at your local hardware store. As far as screw or bolt sizes go, Yamaha has included the size in many of the factory part numbers. Screw, bolt, washer, and nut part numbers usually consist of 3 sets of digits. The middle set contains the size. As an example, the alternator to motor block screw is part #98501-06075-00. The center set of digits, "06075", indicates this is an M6 screw that is 75mm long.
 
That would be part #98580-05010-00 which would make the screw size M5 x 10mm long. There are several spots on this bike where Yamaha cheaped out and used screws shorter than they should have. This is one of them. A 10mm long screw won't utilize all the threads available to it in the cover. This can make it more prone to stripping out. Use a 12mm long screw here instead.
 
I lost one of those and just went my local ACE hardware store, I think it was a M4 1.0 pitch maybe with out checking. I had one left and I took in and sized it on there thread finder. Hope that helps.
 
Hardware stores or fastener stores usually have common sizes (4, 5, and 6mm x 1.0 pitch). They don't carry M8 or M10 x 1.25 pitch though. That big they start carrying 1.5 pitch only. Check Pro Bolt for harder to find bolts/materials.
 
They are a .8 pitch which is standard for an M5 screw/bolt. They are not 1.0 pitch, in fact I don't even think M5 screws are made that way. As I said, get 12mm long ones, the original 10s are too short.
 
Last edited:
teamkandy said:
I lost one of those and just went my local ACE hardware store, I think it was a M4 1.0 pitch maybe with out checking. I had one left and I took in and sized it on there thread finder. Hope that helps.
Click to expand...
M4 is NEVER 1.0 pitch. On the other hand, M6 and M7 is 1.0.
M4 is 0.7 mm pitch, IIRC.
 
Generally, metric fasteners from M3 to and including M8 on japanese bikes and cars are just standard (european industrial) metric, as found in hardware stores. M10 and M12 is mostly 1.25 mm pitch, which is a japanese thing. Standard metric pitch for those is 1.50 and 1.75. M14 and larger is always some kind of fine pitch, but actual pitch varies
 

Similar threads

scott s
Petcock screws fiber washers
Replies
6
Views
972
Jim
Jim
toglhot
Repairing the clutch cover.
Replies
6
Views
202
toglhot
toglhot
Carveacre
Fuel Petcock Screws
2
Replies
22
Views
455
Its been a long time
I
B
Neutral switch lead wire screw?
Replies
8
Views
706
Jan_P
J
toglhot
Hydraulic clutch build.
Replies
9
Views
461
650Skull
650Skull
Back
Top