Author Topic: 1952 A7 valve gear  (Read 1371 times)

Offline duTch

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Re: 1952 A7 valve gear
« Reply #30 on: 10.07. 2018 09:12 »
.......There is a little play in the breather hole that fits on the cam gear wheel pin.......

 Please explain further..  *conf*

........Could the sound be because of the advance retard springs having lost their tension??..
   aaah... *conf2* do you figure that ???
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
Have a '74 850T Moto Guzzi since '92-best thing I ever bought doesn't need a kickstart 'cos it bump starts sooooooooo(mostly) easy

Offline anjimehra

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Re: 1952 A7 valve gear
« Reply #31 on: 10.07. 2018 09:32 »
Timing side noises may be from wear in idler pinion or idler pinion bushes. Also possible that the crankshaft pinion may not be a tight fit on the shaft and is rocking on the woodruff key.
Hi Julian
Thanks., but the bushings have all been changed, & theres no excessive backlash in the gears.

Offline muskrat

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Re: 1952 A7 valve gear
« Reply #32 on: 10.07. 2018 10:15 »
G'day Anji.
Clutching at straws now! I've listened to the video quite a few times now.
With the motor running pull the right hand spark plug cap off, keep it running on the left. Does the noise diminish? Then do the same the other side. This is the standard big end knock test.
Feel free to take more videos with varying revs and the above test and email it to me.
'51 A7 plunger, '57 A7SS now A10CR,  '83 CB1100F, 88 FXST .
Muskys Plunger A7

Online Greybeard

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Re: 1952 A7 valve gear
« Reply #33 on: 10.07. 2018 10:49 »
I have to say, when I recently managed to get a pushrod on the edge of the follower during tappet adjustment, that then dislodged, causing huge tappet clearance, the engine sounded rather like that: