Centre Web Bearing Play?

Information relating to the Matchless G11 or AJS Model 30 600cc twin
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DavidHulse
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Centre Web Bearing Play?

Post by DavidHulse »

Assembling my G11CS crankshaft, I am hoping to re-use the existing centre web bearings, which look reasonably ok, as does the journal. However, when fitted and torqued up correctly, I can feel a small amount of up and down movement, in all directions. I can't actually measure it now it's installed, but I checked the dimensions with a digital caliper before assembly and it all seemed to be right. Is this normal, and does it matter?
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dave16mct
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Re: Centre Web Bearing Play?

Post by dave16mct »

Fit new shells and see if that does it. You need a good fit to maintain oil pressure to the big ends.
Dave.
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1608
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Re: Centre Web Bearing Play?

Post by 1608 »

Agree with Dave, the centre bearing doesn't wear like the big ends and quite often ( provided the journal is not scored ) new shells will suffice.
The centre bearing is merely rotational as opposed to the big ends which take a thumping.
DavidHulse
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Location: Essex UK

Re: Centre Web Bearing Play?

Post by DavidHulse »

Thanks both of you. That all makes perfect sense. I was trying to save unnecessary cost, as these shells are horribly expensive, but it looks like I'll have to bite the bullet!
G15 Roy
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Re: Centre Web Bearing Play?

Post by G15 Roy »

I know a man that thought he would fit the old ones to save less than £100.00 he later had to spend many thousands have it put right. ;)
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DavidHulse
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Re: Centre Web Bearing Play?

Post by DavidHulse »

I'm sure you're right. It would be shame to spoil the ship for a hapeth of tar, as my dad used to say! (hapeth = half penny worth) Thanks.
DavidHulse
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Posts: 56
Joined: Mon Dec 17, 2018 1:49 pm
Location: Essex UK

Re: Centre Web Bearing Play?

Post by DavidHulse »

Have fitted new shells. Seems to have solved the movement problem, although I couldn't discern any difference in the measurement of the old and new shells. Fingers crossed.
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dave16mct
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Re: Centre Web Bearing Play?

Post by dave16mct »

Good result. Thanks for updating us.
Dave.
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