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Discussion Starter · #1 ·
Hi

I am sending my head out (via mail) to have a machine shop do the valve on my triumph. They require i prove the parts and specs. Is the the attached, pulled from the manual all the information they should need?

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Hi Cmattina,
If they are not familiar with old Triumphs, they might find it useful to browse through this beforehand:


regards
Peg.
EDIT: I have just looked up your profile, it appears that you have a 69 T100 500cc, so the posted document will be of little use to the engineering shop as the dimensions within are for the 650cc/750cc Triumphs.
 
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Hi,
sending my head out (via mail) to have a machine shop do the valve on my triumph. They require i prove the parts and specs.
Mmmm ... you're the one that needs their professionalism, for which you are doubtless paying them a large amount of money? So how come you are having to tell them how to do their job? :confused:

If this isn't a "machine shop" familiar with half-century-old Triumph motorcycle engines, is it really wise to give them near-irreplaceable (only expensively-replaceable, if at all) parts without any guarantee they know what they're doing? If they replace valve guides, do they know to remove the carbon before pushing out the old ones? If they don't, the carbon gouges the head ally, oil will run down the gouges, your rebuilt engine will smoke like a coal-fired battleship ... Do they know to pull in new guides concentric with seats? If not, they'll remove vast amounts of irreplaceable hardened valve seat getting 'em concentric with the new guides positions ... From recent threads, if the head is warped, do they know to bend it straight again, not remove near-irreplaceable metal skimming the cylinder mating surface beautifully flat ... while leaving the rocker-box mating surfaces still bent? :oops:

If you have to tell the "machine shop" really basic stuff like valve guide-stem clearances on an air-cooled engine, and you're "sending ... out (via mail)", wouldn't you be wiser sending to a business that knows more about old Triumphs than you do? There are several Canadian-based long-time Forum contributors, if this "machine shop" does know less about old Triumphs than you do, maybe a thread titled, "Recommend a Canadian machine shop that knows old Triumphs?" would be wiser before "sending"? Or can you send to/receive from the US without too much trouble from customs? If so, several US machine shops familiar with old Triumph engines ...

Is the the attached, pulled from the manual all the information they should need?
View attachment 767752
No ... that looks like it's from the Triumph C-range workshop manual? If so, if you look through all the "General Data", you'll see several different valve diameters and port diameters. You know already the head you have isn't original to your bike, how do you know it hasn't been fitted with e.g. oversize valves, and/or the ports modified? In your place, I'd check all the dimensions, and any cast or stamped codes, to try and ensure as far as possible I'd identified the head correctly.

Hth.

Regards,
 

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If the machine shop has done head work on autos , I see no reason to dismiss them , that they are not up on dinosaur Brit bikes , so what ?
A valve stem to inside guide clearance is a simple thing to measure and to fit to the recommended clearances . That they asked for the info
is not a bad thing , there are numerous variations on proper clearances in hundreds of engines . It might be worth asking if they've done many
motorcycle engines , if not , then that's of concern . Good luck . Peter
 

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Discussion Starter · #6 ·
If the machine shop has done head work on autos , I see no reason to dismiss them , that they are not up on dinosaur Brit bikes , so what ?
A valve stem to inside guide clearance is a simple thing to measure and to fit to the recommended clearances . That they asked for the info
is not a bad thing , there are numerous variations on proper clearances in hundreds of engines . It might be worth asking if they've done many
motorcycle engines , if not , then that's of concern . Good luck . Peter
They did my Ariel last year. But the language in the Ariel manual is easier to follow, for me at least. So I just wanted to confirm that the specs within the screenshot I shared are all that is needed, as I was just going to print that off and include it in the box
 
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