Author Topic: Tappet clearance  (Read 871 times)

Offline Tone

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Tappet clearance
« on: 13.08. 2019 18:21 »
Hi all, Could someone please tell me what is the correct tappet clearance for a 1953 A10 plunger, engine number starts BA10.  Thanks.

Online Greybeard

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Re: Tappet clearance
« Reply #1 on: 13.08. 2019 19:47 »
This is very useful: http://www.bsawiki.com
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Offline trevinoz

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Re: Tappet clearance
« Reply #2 on: 13.08. 2019 22:31 »
As been posted many times, it depends on which camshaft is fitted.

Online muskrat

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Re: Tappet clearance
« Reply #3 on: 14.08. 2019 07:33 »
G'day Tone.
It had a 334 cam as std A10 50-58 (30, 70, 65, 25). Tappets are 10 & 10.
If it has the later 356 cam A10 58-61 (42, 62, 67, 37). Tappets are 10 & 16.
The only way to tell is to set up a degree wheel on the crank and see when the valves open and close. The cam # is on the blind end of the cam so it's a motor split to read it.
Cheers
Disclaimer: these figures are from the Roy Bacon book. known to have a few errors!
'51 A7 plunger, '57 A7SS racer now a A10CR, '78 XT500, '83 CB1100F, 88 HD FXST, 2000 CBR929RR ex Honda Australia Superbike .
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Muskys Plunger A7

Offline duTch

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Re: Tappet clearance
« Reply #4 on: 14.08. 2019 10:23 »

 and with a Alloy head will be different again?
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
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Offline trevinoz

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Re: Tappet clearance
« Reply #5 on: 14.08. 2019 22:37 »
Musky, you are idiot about face with those figures.

Offline Tone

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Re: Tappet clearance
« Reply #6 on: 15.08. 2019 09:47 »
Thanks guys, I’m going to try 10/16 see how it goes.  It’s all standard apart from Srm bearing conversion and there oil pump etc. I’m sure I read a few years ago when I had my swing arm a10 that you can set at 8/8 through out the range! Course I could have dreamt it!! Cheers

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Re: Tappet clearance
« Reply #7 on: 15.08. 2019 11:32 »
G'day Trev. *smile*
Read disclaimer. Not surprised!
Both my A's won't run on the recommended settings with alloy heads and 357 cams. Both propped the valves open after 10 miles. I had to add 2-4 thou.
Cheers
'51 A7 plunger, '57 A7SS racer now a A10CR, '78 XT500, '83 CB1100F, 88 HD FXST, 2000 CBR929RR ex Honda Australia Superbike .
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Muskys Plunger A7