AF Mammoth Head

[Gtwildcat]

Anyone using 1 of these heads? Any good? Much benefit over the standard type head?

[ROClarke]

I have to say I am tempted,there is no meat on my TS1head which can't help cooling and potential warping issues.

[Fast n Furious]

I have commented on this sort of matter before.
A head that has a larger fin diameter than standard will require an oversized cowling.
This new cowling can no longer hug the cylinder like it used to.
Because there is now a cavernous gap between the cylinder and the cowling, most of the cooling air will follow this path of least resistance and exit without having performed any useful work.
These oversized heads are good at conducting heat from the combustion chamber but your cooling system is now pathetic at convecting the heat from the head and the cylinder away.
Not the best way forward in my opinion.

[hullygully]

I just put one on my TSuno (not run it yet ), they are mahoosive - yes, have a different cowling to std - yes, have loads of slots in the base so wouldn't halt the air flow, take off more heat than std so will keep cooler better, longer

[Scooterlam]

I have commented on this sort of matter before.
A head that has a larger fin diameter than standard will require an oversized cowling.
This new cowling can no longer hug the cylinder like it used to.
Because there is now a cavernous gap between the cylinder and the cowling, most of the cooling air will follow this path of least resistance and exit without having performed any useful work.
These oversized heads are good at conducting heat from the combustion chamber but your cooling system is now pathetic at convecting the heat from the head and the cylinder away.
Not the best way forward in my opinion.

An interesting take

[coaster]

I had one of Ron Moss's Avanti heads and cowls on my TS1 and never had any overheating issues other than the air leak that finally killed it. I can understand the thought about 'forced' air but in reality I suspect that convection is the main factor.

[Rich Oswald]

I have commented on this sort of matter before.
A head that has a larger fin diameter than standard will require an oversized cowling.
This new cowling can no longer hug the cylinder like it used to.
Because there is now a cavernous gap between the cylinder and the cowling, most of the cooling air will follow this path of least resistance and exit without having performed any useful work.
These oversized heads are good at conducting heat from the combustion chamber but your cooling system is now pathetic at convecting the heat from the head and the cylinder away.
Not the best way forward in my opinion.

Do you think a re designed "stepped" cowling would work then?

[Storkfoot]

I am in the process of buying one for my TS1. The thought occurred to me about air flow around the cylinder but I went with the recommendation I received and also something I found on a 2 Stroke website which talked about oversized and heavily finned heads dissipating heat away from the cylinder itself.

[Scooterdude]

I have commented on this sort of matter before.
A head that has a larger fin diameter than standard will require an oversized cowling.
This new cowling can no longer hug the cylinder like it used to.
Because there is now a cavernous gap between the cylinder and the cowling, most of the cooling air will follow this path of least resistance and exit without having performed any useful work.
These oversized heads are good at conducting heat from the combustion chamber but your cooling system is now pathetic at convecting the heat from the head and the cylinder away.
Not the best way forward in my opinion.

Do you think a re designed "stepped" cowling would work then?

Would have to be in two halves bolted together to get it to fit.

[lozmondo]

I run a big head TS1 with no cowling or fan at all (the heads MB do)
My cht ran cooler with this than when it was standard cowled

[Fast n Furious]

There is nothing wrong with standard sized heads providing they have sufficient density. (At least 900grams for a large block) Some Serveta heads were only 700g which can cause problems.
TBH. The main problem with lammy cooling is to do with the number of holes in and around the cowling where air can pass without it doing anything. The gap around the exhaust manifold and at the rear of the cylinder is where most of the air pisses out. Sort this out and all cooling problems disappear.

[Warkton Tornado No.1]

There is nothing wrong with standard sized heads providing they have sufficient density. (At least 900grams for a large block) Some Serveta heads were only 700g which can cause problems.
TBH. The main problem with lammy cooling is to do with the number of holes in and around the cowling where air can pass without it doing anything. The gap around the exhaust manifold and at the rear of the cylinder is where most of the air pisses out. Sort this out and all cooling problems disappear.

I agree with much of what you have said on here, especially about forced air cooling, though I believe many under-estimate the benefit of having sensible sized bleeds on their exhausts, which whilst smaller pipe diameters may add torque, they inevitably will also add heat.

(In fact, unless I missed it ( ) some of us are still waiting for images you said you would post in relation to how you went about modifying your cowlings, though if I recall, you were waiting for a more convenient time/rebuild )

[Fast n Furious]

Yep...... The scoot has 5000 very reliable, very thrashed miles on it now and is desperately in need of a rebuild.
i can feel an increase in vibration and a drop in top end power.
I was going to do it before Cleethorpes but its too late now.
I shall risk it and hope it doesn't let me down.
I will have to do it next week though, hopefully I'll have my club mates machines out of my man cave by then?
So.... photos and details to follow very soon.

[Storkfoot]