Megacycle Cam clearance....

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The clearance for Megacyle 560 cam is quoted as 16 thou clearance inlet and exhaust, this is their lowest road cam grind , has anyone tried different clearances? 560 NR
 
The clearance for Megacyle 560 cam is quoted as 16 thou clearance inlet and exhaust, this is their lowest road cam grind , has anyone tried different clearances? 560 NR
With iron barrel and std alloy pushrods , the recommended running clearances are 0.13 both inlet /exh, (checked on Old brits).
 
The cam has nothing to do with expansion of the barrels.

Stop twisting things, different cams have different clearances (you do realise that?) My full race cams use 8/10thou, so I set clearances at 2 and 4 thou

Maybe you should measure the expansion rate of the barrel and pushrods to see how much they grow by

So, the setting for a cam with 8/10 would be different from a cam with 16thou
 
Stop twisting things, different cams have different clearances (you do realise that?) My full race cams use 8/10thou, so I set clearances at 2 and 4 thou

Maybe you should measure the expansion rate of the barrel and pushrods to see how much they grow by

So, the setting for a cam with 8/10 would be different from a cam with 16thou
I just followed Steve Maney's recommendation. So, argue with him jf you must.
 
I just followed Steve Maney's recommendation. So, argue with him jf you must.

I have known Steve for over 30 years

The recommendation is for his cams, but the barrel/ steel pushrod combo grows by approx 6 thou

Other cams specify 16thou clearance.........
 
I've had the combo for 12.000 miles. Quiet valve train, no blow by, excellent power from idle, great fuel consumption. I suppose I have to be wrong then.
 
Stop twisting things, different cams have different clearances (you do realise that?) My full race cams use 8/10thou, so I set clearances at 2 and 4 thou

Maybe you should measure the expansion rate of the barrel and pushrods to see how much they grow by

So, the setting for a cam with 8/10 would be different from a cam with 16thou
I check the tappet clearances when the motor is hot and set them at 2 and 4. Altering the clearances alters the cam timing equally at both ends of the duration. The closer the clearances are - usually the better the timing. If you use methanol fuel, the motor does not get as hot as it does with petrol. If I was using aluminium barrels, I'd have difficulty getting enough heat into the motor. With petrol, I'd sett the clearances a little wide, then ride the bike until the motor was really hot, then reset the clearances closer. It is what works which is important -not the theory.
 
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What you need to be careful of are 'ramp cams'. Quietening ramps confuse the issue. They usually run with wider clearances. But I have even run those close.
Another consideration is the type of head gasket. If it settles, the clearances might become reduced and the valves might not seat properly. The specified clearances are probably worst case scenario.
 
I doubt that that the cam manufacturers specify a lash clearance capriciously. I am not a cam expert, but it stands to reason that lash setting determines when and where the tappet makes contact with the cam's profile which then defines the point where the cam begins accelerating and ends it's decelerating.

I can also understand that a builder who employs a barrel and/or pushrods made from material different from "stock" will probably cause the builder to alter the lash settings.

If, like me, you are not an expert in camology I suggest following the manufacturers instructions. If you choose to venture into this area without anything more than good intentions I suggest that you seek advice from someone who is an expert before your good intentions turn into good riddance.

Best.
 
I check the tappet clearances when the motor is hot and set them at 2 and 4. Altering the clearances alters the cam timing equally at both ends of the duration. The closer the clearances are - usually the better the timing. If you use methanol fuel, the motor does not get as hot as it does with petrol. If I was using aluminium barrels, I'd have difficulty getting enough heat into the motor. With petrol, I'd sett the clearances a little wide, then ride the bike until the motor was really hot, then reset the clearances closer. It is what works which is important -not the theory.

What theory? The ally barrel grows by 6 thou. Reduce your clearnace by 6 thou and you will be correct

Different cams have different ramps. A 4S is spec'd at 16thou clearance, a standard one isn't

My grandmother already knows how to suck eggs
 
Now you have me worried

I installed a Megacycle 5600 cam into my 73 standard 850 years ago and run 08 and 06 assumed it was the same stock
what should I be running for clearances?
 
Megacycle Cam clearance....
 
I am not talking about Maney pushrods or an alloy barrel, this is a road MK3 , so according to the chart it is .013?.... I thought on the original paper work, now lost it said .016?.....
 
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