Author Topic: Rocker box- is this right?  (Read 802 times)

Offline muskrat

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Re: Rocker box- is this right?
« Reply #15 on: 29.07. 2019 20:35 »
G'day butch.
A sheet of 1/4" glass on a flat surface like the kitchen bench top (wait till the wife's away) is well good enough. A little moisture (water or oil) on the glass will hold a sheet of wet & dry paper flat and still. I've done many this way and get them to within a thou".
Cheers
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Online Duncan R

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Re: Rocker box- is this right?
« Reply #16 on: 30.07. 2019 13:20 »
Hi All - many thanks for the tips
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Offline Peter Gee

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Re: Rocker box- is this right?
« Reply #17 on: 01.08. 2019 21:27 »
I would certainly say the culprit is the RockerBox faces...I found .0002+ clearance with my head, which is a very good one even on a NOS rockerbox I had in tock. Have the Rocker Box milled dead flat on the surfaces, which those machinists with cylinder head refinishing grinding wheels ( huge vertically mounted things) will have.

Offline cyclobutch

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Re: Rocker box- is this right?
« Reply #18 on: 02.08. 2019 08:48 »
G'day butch.
A sheet of 1/4" glass on a flat surface like the kitchen bench top (wait till the wife's away) is well good enough. A little moisture (water or oil) on the glass will hold a sheet of wet & dry paper flat and still. I've done many this way and get them to within a thou".
Cheers

Of course, paper not paste. Duh. Thanks.
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Offline Peter Gee

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Re: Rocker box- is this right?
« Reply #19 on: 05.08. 2019 16:05 »
Had this prob too. After checking a NOS box I have to hand, never used..it too had about  2 thou " warp. Seems they made  them like that. I got it down to a thou with plate glass and emery No 800 and will leave it and hope three bond does the rest!

Online Greybeard

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Re: Rocker box- is this right?
« Reply #20 on: 05.08. 2019 16:41 »
My feeling is that a rocker box should easily flex to mate the cylinder head.

Online ironhead

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Re: Rocker box- is this right?
« Reply #21 on: 06.08. 2019 04:59 »
My feeling is that a rocker box should easily flex to mate the cylinder head.

Sorry GB that's a bad feeling, They've both got to be flat.
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Online JulianS

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Re: Rocker box- is this right?
« Reply #22 on: 06.08. 2019 09:34 »
The cylinder face also needs to be flat or the head will flex..........

Online Greybeard

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Re: Rocker box- is this right?
« Reply #23 on: 06.08. 2019 10:18 »
My feeling is that a rocker box should easily flex to mate the cylinder head.

Sorry GB that's a bad feeling, They've both got to be flat.
I wasn't thinking huge distortion; just a few thou.

Online Duncan R

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Re: Rocker box- is this right? UPDATE
« Reply #24 on: 13.08. 2019 14:58 »
Rocker box was tidied up with the wet n dry and plate glass method - came out pretty well, placed it back on the head- shockingly bad and still pivoting on a high point on the head and could get a 25 thou feeler gauge in the gap! Also discovered a high point on the head, appears to be on the face that separates the cylinders. The whole lot has gone of for refacing to a local engineer, had to knock the guides out which will need replacing. So with all those issues not a chance in hell of getting it oil tight.

Hopefully this will sort it once and for all- will keep you posted.
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Offline bikerboy

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Re: Rocker box- is this right?
« Reply #25 on: 15.09. 2019 13:15 »
SRM are doing a one piece rocker box gasket for A10's. I used one for the first time on a recent build and must admit its a nice gasket and does make it a bit easier to fit the rocker box

Online Duncan R

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Re: Rocker box- is this right?
« Reply #26 on: 18.09. 2019 12:51 »
Hi Bikerboy,

I also used the SRM gasket and found it stayed in place whilst fiddling around with the pushrods - would definitely use again.

Update on my oil leak issues- my mate who  resurfaced the gasket faces had to take 1mm off the cylinder head to rockerbox  gasket face to true it up ! so seriously warped. Only 5thou off the cylinder to head face. Almost oil tight got a very slight weep which is still being investigated.
Anglo - Indian A7SS (Actually is a 650)
Kawasaki ZZR 1100
BMW R80GS
BMW R1100GS