Bolt size - camshaft sprockets - Yamaha XJ600

alan

When I use a 9mm wrench it will not fit and a 10mm is way too loose.

It is too tight for a box end wrench to get in there so an open end seems to be my choice, but none fit. I tried a few from different sets and one was new.

There is a # 8 on the head of the bolt. Is that a size indicator or possibly a hardness indicator?

Can someone explain? What are my options?

pd · Posted: Tue May 11, 2010 8:24 pm Post subject:

The 8 on the bolt head is likely the hardness . Have you tried SAE wrenches ?

I have found that sometimes they fit perfectly .

If you need new bolts ( Say you had to cut them off ... ) , here's the part # :

BOLT, FLANGE 90105-07004-00 $.98 ea.

Rizingson · Posted: Wed May 12, 2010 8:32 am Post subject:

The number 8 could be either size of the bolt shank or hardness indicator for a us bolt. Check this link for further info

http://www.boltdepot.com/fastener-information/Materials-and-Grades/Bolt-Grade-Chart.aspx

Also the best socket to use is a 6 point Snap-On of proper size. Many of the cheaper sets especially a 12 pt socket will slip and ruin the bolt.

zjeppe · Posted: Wed May 12, 2010 12:07 pm Post subject:

Definitly a 10mm.head, but use a highquality 6 pan wrench Exclamation

If this is already to loose, bolthead is ruined.As the "10" is one of the most common& vulnarable sizes on jap bikes, buying good tools of that size really pays of.Gd luck& keep us posted.

alan · Posted: Thu Jun 10, 2010 9:10 am Post subject:

I tried new wrenches and good quality ones but they were no better. I ended up turning the sprocket so I could get better access. The instructions warned against doing this so not sure. However when I turned the sprocket it was easy to remove and I got the sprocket etc removed and then I removed the head and valves. Then I cleaned up the head, ports and valves and now I am in the process of grinding the valves.
Havin a great time doin it.

Thanks for all the thoughts/suggestions. I will store them away for future use.
Al