choosing a cam
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- Minor Maniac
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Re: choosing a cam
The valve seat angles are 45 degrees and as regards the size of cutter you need to use the largest cutter you can get into the combustion chamber as you need to cover the whole width of the valve seat.
For the inlet...............36mm (min).
For the exhaust...........32mm (min).
Phil
For the inlet...............36mm (min).
For the exhaust...........32mm (min).
Phil
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- Minor Friendly
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Re: choosing a cam
Well i have ported the head, cut and lapped in the valves, so the head it pretty much ready to go on.
But i have been fitting the Duplex Timing Gear and chain set up this evening but have run in to a few problems.... The gear on the crank was sitting to proud compared to the one on the cam, so i removed some of the shims. I got the gears pretty close to lining up but now with the chain on its getting caught on the 2 bolt heads below the crank. so not to sure if i need to shim out the cam gear then the crank?
But i have been fitting the Duplex Timing Gear and chain set up this evening but have run in to a few problems.... The gear on the crank was sitting to proud compared to the one on the cam, so i removed some of the shims. I got the gears pretty close to lining up but now with the chain on its getting caught on the 2 bolt heads below the crank. so not to sure if i need to shim out the cam gear then the crank?
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- Minor Addict
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Re: choosing a cam
Those two bolt heads catching on the chain might be the one's you have to counter sink so they are flush with the plate, did you get two counter sink bolts with the chain and sprocket set ?
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- Minor Friendly
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Re: choosing a cam
No i was not aware i needed them and it did not come with any. I have ground the heads of the bolts down a bit but it must need a little more off them.
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- Minor Addict
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Re: choosing a cam
No you replace them with counter sunk screws that end up flush with the plate they are screwed through. It is best to use Allen headed type screws and set them in with a drop of thread lock.
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- Minor Friendly
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Re: choosing a cam
Oooh ok i see what you mean now, i just had a quick look on minispares so i shall get some tomorrow.
Thanks very much
Albert
Thanks very much
Albert
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- Minor Friendly
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Re: choosing a cam
well just pooped up to the shed and remembered that i still have the old drum brakes from when i converted to disks. so i found the drum screws and they worked perfectly after counter sinking.
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- Minor Addict
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Re: choosing a cam
Make sure you put a bit of thread lock on them though as you cannot tighten them as much as bolts with heads on.
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- Minor Maniac
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Re: choosing a cam
These screws are better in that they can be torqued to the required setting if required.
http://www.minispares.com/product/Class ... .aspx|Back to
When countersinking ensure that a 90 degree countersink is used.
As above put a smear of Loctite thread lock on the threads of the screw.
[frame]
[/frame]
Phil
http://www.minispares.com/product/Class ... .aspx|Back to
When countersinking ensure that a 90 degree countersink is used.
As above put a smear of Loctite thread lock on the threads of the screw.
[frame]
Phil
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- Minor Friendly
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Re: choosing a cam
Ok will do 

Re: choosing a cam
If you have a chain with a 'link' in it (not common - but there are some about) - make sure the link is on the outside - not inside.



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- Minor Friendly
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Re: choosing a cam
No link on this one Roy but thanks for the thought, now off to put the head back together
Re: choosing a cam
Looking at the photo’s of the crank showing the big end fixing nuts,what sort of socket do I need to remove these,my torque set do not seem to fit.
Many thanks,
Martin.
Many thanks,
Martin.

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- Minor Fan
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Re: choosing a cam
Big ends are 9/16 AF. You need 12 pointer sockets, not 6.
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- Minor Maniac
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Re: choosing a cam
Whether you need a 12 point or six point socket depends upon what big end bolts you have fitted.
A photo of the big end bolts would help.
A photo of the big end bolts would help.
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- Minor Fan
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