Other Girdled head bolt types??

[Freakrider]

61x Cylinders are prone to break on the intake/carb side and the pro tec half girdle is on the intake/carb side...62t's have beefed up casting...

 

[RyanO]

.....im confused.


read the 2nd to last sentence in post #1 and then read post #4.

if it does bolt the cylinder to the cases then its like comparing apples to oranges when compared to the ADA kit.

The sharkfab setup bolts the cylinder to the case and then sandwhiches the cylinder when you torque the head on.

The ada setup just sandwhiches the cylinder to the cases when you torque the head on.

Thus with the ada setup if you un torque the head, the cylinder is no longer torqued to the case.

 

[Freakrider]

The sharkfab setup bolts the cylinder to the case and then sandwhiches the cylinder when you torque the head on.

The ada setup just sandwhiches the cylinder to the cases when you torque the head on.

Thus with the ada setup if you un torque the head, the cylinder is no longer torqued to the case.

It takes good force to crack the cylinder loose off the dowel pins/gasket seal and the ADA set up has been proved over time to work well...

 

[FlightPlanDan]

It takes good force to crack the cylinder loose off the dowel pins/gasket seal and the ADA set up has been proved over time to work well...

I see what you're saying now. I was basing my opinion on pics of broken cylinders...not broken at the base. But I'm curious;
The sharkfab "type" (don't wanna single out sharkfab) ...Does anyone know anyone who's cylinder broke with any type of full girdle?

Not trying to knock ADA. Hell, it's on my ski.

 

[Freakrider]

I see what you're saying now. I was basing my opinion on pics of broken cylinders...not broken at the base. But I'm curious;
The sharkfab "type" (don't wanna single out sharkfab) ...Does anyone know anyone who's cylinder broke with any type of full girdle?

Not trying to knock ADA. Hell, it's on my ski.

to clarify: added info

It takes good force to crack the cylinder loose off the dowel pins/gasket seal (when the head & girdle bolts are removed) and the ADA set up has been proved over time to work well...

 

[munki63]

Another thought on the sharkfab style, when you torque down the cylinders, your pulling up on the case bolts right? Or am I out to lunch?

 

[Endo]

Another thought on the sharkfab style, when you torque down the cylinders, your pulling up on the case bolts right? Or am I out to lunch?

That was my thinking, If the head bolts are torqued higher than the case bolts you are doing the same thing the ADA system does.

 

[augustaf]

riva used to make a girdle kit like this but the base bolts used to break.

the problem was the upper part of the base bolts were drilled and tapped too far and made the metal too thin and prone to cracking and breaking. IDK if these other companies have addressed the problem.

I suppose that the sharkfab had "addressed that problem". Can't know for sure, they seemed to have discontinued the girdle kits, now none seem to make them.

 

[eastbay]

im running a 62t motor 180psi....im thinking of just not running the girdles? not have to worry about it....

ive allways had a girdle head on eveyone of my skis so i dont know how it would do without it....

TBM has a beefy setup too.

 

[KTM434]

I have one motor with the Riva girdled head (same style girdle bolts as sharkfab) I have not had any issues and my motor is a Riva ported big bore 61x cylinder (the ones that are known to crack at the base) on 62t cases. I also have another motor with an ADA girdled head. I can say that the ADA is the only true girdle design because there is no pressure on the cylinder base where they are prone to crack yet the other style does put pressure on that area (torquing the head to those shark fab style girdle base bolts doesnt release the pressure from the cylinder base flange like previously stated). It is still a girdle setup and much better than non girdled but not quite as well designed as the ADA. The cause of the infamous cylinder base cracking is more commonly seen on modified engines running high compression but has been seen on stock setups as well. The 61x cylinder has a thinner base flange on the intake side compared to the thicker exhaust side and thats the side that is known to crack. The cause of the cracking is the very high compression pressures in the combustion chamber at TDC especially with advanced timing... That pressure of the igniting air/fuel mixture while the piston is still traveling upward compressing that explosion (the explosion/ignition of fuel/air mixture is what forces the piston down (power stroke)) causes extreme pressure in the cylinder and if the piston is still traveling upward then the pressure all transfers to the head dome and that combustion pushes up on the head. The head design is bulletproof how it torques to the cylinder so no damage happens there so that pressure is transferred to the cylinder. That same pressure pushing up on the head is also pulling the cylinder up with it and the weak link is that smaller flange so those extreme pressures cause this flange to crack.
I hope that makes sense to you guys when you read it cuz I tried to explain it in depth so it makes sense but sometimes I trip over my words

Edit: Using the ADA style girdle bolts removes all upward pulling pressure from the cylinder base therefore you would never have that failure of cracking the cylinder base flange. Worst case scenario is you maybe blow a gasket although very unlikely but still much cheaper and better than cracking a cylinder. Especially if you have already invested money on porting or big bore sleeves, etc.
Hope that helps guys