anyone care to explain this to me?

 

case matching is when you split the engine case halves and match each case half to the lower tranfer port openings of the cylinder as to not have any restrictions in air flow, on blasters you can also modify the oiling holes for better lube and the galleries can be removed for added volume.

 

galleries?

 

somehow I knew someone was going to ask that, how bout this, the little trough that leads to the main bearing oiling holes, you can remove it for added crankcase volume if you chamfer and enlarge the oiling holes.[img]i/expressions/face-icon-small-shocked.gif[/img]

 

This is a major performance inhansment after porting and the case halves are not needed to be split as potentpete stated. Case matching is simply done by transferring the transfer port tunnel size to the case and easily done by using a gasket that has been opened to the tunnels and then used as a template to mark the cases and then with a dremel or die grinder that area is then opened up to the same amount as the template markings to increase flow and reduce restriction. BTW I myself did this to my Banshee and it is a major increase as to how far the motor now revs out to, not to mention increasing my main jets several sizes.

 

that's ok if you don't want to split the cases, but all those metal grindings go right down into the main bearings, so to do it properly, its advisable to split the cases and remove the bearings, because no matter how well you wash the bottom end out, those metal shavings are still going to be in the main bearings if you don't split the cases.

 

Your right but here's a trick I used and it got them all out. I first used a rag to cover as much as I could, then I used a gallon of wd-40 to wash out the crank and my shop vac with a piece of hose taped to it, this left it super clean as the wd-40 washed out the crank and made the chipping fall to the bottom as I turned over the motor several times and then used the vac to suck out the wd-40 and the shaving that are fell to the bottom.

 

that would still make me nervous, because those shavings are still trapped between the main bearing and the seals, there's no way to suck them outta there unless you take it apart, been there, done that.[img]i/expressions/face-icon-small-sad.gif[/img]