650 ss tappett adjustment

hillbone

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Hi again.
When adjusting my tappets, I would have imagined that approximately the same amount of thread on the adjusters would measure the same. But there is a big difference between the 2 inlets left and right and the same with the exhaust. When refitting the head, i triple checked each pushrod and dropped nicely into cam followers and each pushrod is correctly seated into each rocker. 2x
My logic tells me the thread adjutment should be roughly the same.
Thoughts please.
Cheers
 

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hillbone said:
Hi again.
When adjusting my tappets, I would have imagined that approximately the same amount of thread on the adjusters would measure the same. But there is a big difference between the 2 inlets left and right and the same with the exhaust. When refitting the head, i triple checked each pushrod and dropped nicely into cam followers and each pushrod is correctly seated into each rocker. 2x
My logic tells me the thread adjutment should be roughly the same.
Thoughts please.
Cheers
Click to expand...
Did you checked the lenght of both pushrods ? as the pre 125871 are 2.5/3 mm longer than later one ....
 
Hi. Both inlet pushrods are same length and exhaust pushrods are same length
 
Is this a new build? If not the ball/nubs on the adjusters may have worn into the valve stems. Years ago in the shop I would put hardened lash caps on to rectify this problem. Otherwise customers were on the hook for a valve job if the stems were too bad.
 
Thomasa said:
Is this a new build? If not the ball/nubs on the adjusters may have worn into the valve stems. Years ago in the shop I would put hardened lash caps on to rectify this problem. Otherwise customers were on the hook for a valve job if the stems were too bad.
Click to expand...
Hi. No its a rare paul dunstall delivered new bike, very low milage that was featured on the cover of classic bike magazine. But the last owner really messed with it and fiddled with just about everything. Im thinking of tearing it down from scratch and starting over. Im not new to nortons as ive had quite a few from 40 years back. Thanks mate.
 
hillbone said:
Hi again.
When adjusting my tappets, I would have imagined that approximately the same amount of thread on the adjusters would measure the same. But there is a big difference between the 2 inlets left and right and the same with the exhaust. When refitting the head, i triple checked each pushrod and dropped nicely into cam followers and each pushrod is correctly seated into each rocker. 2x
My logic tells me the thread adjutment should be roughly the same.
Thoughts please.
Cheers
Click to expand...
If the valves all open an close and you don't hear anything odd, you're probably OK. Also, hard to tell form the picture angle, but the adjusters look like they are different lengths - take a look at all four and see if they are the same lengths or not.
 
Maybe it's the angle but the valve stems appear to be unequal.
 
marshg246 said:
If the valves all open an close and you don't hear anything odd, you're probably OK. Also, hard to tell form the picture angle, but the adjusters look like they are different lengths - take a look at all four and see if they are the same lengths or not.
Click to expand...
All adjusters and pushrods same lengths. As in, the inlets are same etc.
 
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