tappet adjusting screws

[WayneO57]

Hi all
I'm looking for 2 x M6 tappet adjusting screws new or in excetpional condition for early model 125.
160cc used the same rockers and have the same size adjusters, not sure about 100cc.
Been looking around for weeks since I sourced some rockers from Thailand.

Appreciate any help
Wayne

[Jordan]

If you cannot find the swivel foot type adjusters, you can possibly use a simple grubscrew type with a valve cap.

[WayneO57]

Thanks Jordan

I hadn't thought of that
Got a bit of tunnel vision about the insides of the motor.
I'm wanting to replace as little as possible but trying to use "original" parts.
So If not available it is a great way to get the top finished

Wayne

[ducwiz]

But adding a cap changes the rocker's angle of action. This leads to higher transverse forces in the valve guide, so in turn wear is increased. A rule of thumb says, that the rocker's dotted function line and the valve's dotted center line should include 90° at half of the valve's stroke. As Dr. T. shure enough knew this fact, the condition is kept supposedly with the original valve stem length.

cheers Hans

[Jordan]

That is a fair point.
I can't remember - is there a difference in length of valves, for the swivel foot vs solid rocker + valve cap (shim)?

It's probably good to keep geometry correct according to the theory, as valve guides would be affected, and they are quite short on our engines.

[WayneO57]

Thanks guys

Your getting into theory I have never heard of as a real novice restorer.

I can put em together & usually get them running but need wiser heads than me to make them purr like they are supposed to

Wayne

[WayneO57]

Forgot to mention this BUT it still doesnt help me find another set of M6 adjusters.

Any Ideas on where I maybe lucky enough to find some ?

Wayne

[Jordan]

Just to check, it's definitely 6mm thread you want?
8mm elephant foot adjusters are easy to find, the same size as on 250 Monza.

[WayneO57]

Hi Jordan
They are definitely M6.
Rocker arms appear too light to put M8 in them.
Hopefully the new parts just might be a little stronger & I can use M8
Wayne

[Rick]

Wayne,
I measured the adjuster screw from a rocker arm on my 160 head, and it was 8mm- the 160 parts manual show part number:
0500.92.660 Adjustment screw 8MB
If you're sure your rocker arms are from a 125, then the arms aren't the same as a 160 Monza Jr.
Rick