300 base gasket choices?
- Thread starter husley
- Start date
djroggen
New member
All bikes are different, and require a different stack for the same/similar characteristics. My 300, I believe I have 2 thick, and 1 thin gasket. The amount of gaskets do not matter, it is how they line up in comparison to the piston in bottom dead center. I put the piston at BDC and made it level with the exhaust port.
This made my bike into a torque monster.
It is so linear, it is unreal. I just twist the throttle and it hooks up and lugs like no other.
This made my bike into a torque monster.
It is so linear, it is unreal. I just twist the throttle and it hooks up and lugs like no other.
twowheels
New member
They come in 0.15, 0.30, and 0.50mm versions, so mix and match to your heart's content. Just remember your compression is changing along with your port timing when you change the stack.
Jakobi
Super Moderator
Compression ratio changes, and so does your squish clearance. A stock head will have a decent clearance to start with so moving the cylinder lower will tighten up that clearance, increase compression, and move power curve downwards (both through comp and port timing).
Setting the piston edge flush with the base of the exhaust port at bdc is your configuration for peak HP. Usually takes a bit from the bottom and stuffs it up top.
Before just slip slop slapping any old stack in there I'd think about what you want to achieve. Then set the stack, and then have someone machine the head to suit that stack and your purpose and fuels. I wouldn't drop 1mm of gaskets out without checking the port timing and squish clearance first. I'd probably CC everything before pulling it down to calc the CR too.
Setting the piston edge flush with the base of the exhaust port at bdc is your configuration for peak HP. Usually takes a bit from the bottom and stuffs it up top.
Before just slip slop slapping any old stack in there I'd think about what you want to achieve. Then set the stack, and then have someone machine the head to suit that stack and your purpose and fuels. I wouldn't drop 1mm of gaskets out without checking the port timing and squish clearance first. I'd probably CC everything before pulling it down to calc the CR too.
husley
Bronze Level Site Supporter
Thanks
Thanks for everyone's input, very informative. But I am missing a part of the puzzle:
I would like more low end and I am willing to sacrifice top end for torque. In order to do this I would use a thinner or thicker base gasket set (relative to the existing/stock)?
If I get a Wossner top end kit will it have all the gasket thickness I need to chose from or would I order them seperate from gofasters, etc?
Thank!
J
Thanks for everyone's input, very informative. But I am missing a part of the puzzle:
I would like more low end and I am willing to sacrifice top end for torque. In order to do this I would use a thinner or thicker base gasket set (relative to the existing/stock)?
If I get a Wossner top end kit will it have all the gasket thickness I need to chose from or would I order them seperate from gofasters, etc?
Thank!
J
pscook
Platinum Level Site Supporter
From my homework, thinner base gaskets increases bottom end at sacrifice of top end and thicker gaskets increases top end at sacrifice of bottom end. If you set the piston even with the floor of the exhaust port you get great top end. Having the piston above the port floor moves the power lower in the revs. The explanation is that having the piston low enough to fully expose the open port, and then close it early in the compression cycle, provides lots of power at full RPM. Having the piston above the floor at BDC reduces port opening at BDC but closes later on compression, providing low end performance.
Confused yet? Thick gasket stack = top end, thin stack = bottom end (all other things being equal). Make sure to confirm your squish is no less than 1.2mm and no more than 1.8mm when all is said and done. Anything outside of that needs some professional help cutting the head.
Jakobi
Super Moderator
Spot on. My 300 came with 1.3mm worth of gaskets to time the ports for top end. I think the newer ones come with 0.5mm.
Basically Husley, if you want to boost the lower grunt you'll want to put less gasket in there. To do this though you'll need to measure up what you already have in there. I'd take a squish measurement before hand too. The problem is if on the rare chance that you have a perfect squish measurement already and take a gasket out you might (rare) get piston to head action. It will also increase your compression ratio.
I'm with Steve. Stock gaskets, Wossner Kit, and a fresh little end bearing!
Basically Husley, if you want to boost the lower grunt you'll want to put less gasket in there. To do this though you'll need to measure up what you already have in there. I'd take a squish measurement before hand too. The problem is if on the rare chance that you have a perfect squish measurement already and take a gasket out you might (rare) get piston to head action. It will also increase your compression ratio.
I'm with Steve. Stock gaskets, Wossner Kit, and a fresh little end bearing!
