Рет қаралды 15
They told me not to bother trying to big-bore this saw, but @AFleetCommand clearly shows a ~10% spread between his 54mm & 56mm jugs (which makes sense, as it's a 7.5% displacement or piston-surface increase, and power increases over-linear in relation to displacement) The thing is that, of course, you need to port these big bore top ends for 7.5% more throughput (or 10%, this would be up for debate, but either figure is still short of what Blair would recommend based upon the OEM carb bore), turns out that while this is possible, you cannot JUST widen your ports because you'll find yourself holding a jug whose intake port would've eaten the ring-end (not that I'd know anything about that...)
SO... This is a new vendor, NewJ's, and there's NO ring-of-death unplated top so this will be a 2-ring build now (2 Caber rings on ported Hyway pop-up piston), the plating is crazy shiny almost like no cross-hatching (but there is cross-hatching, however thin/surface-y it is), the piston's cross-hatching is some of the deepest I've ever seen and its piston's skirts are about mid-way thickness between farmertec 56mm, and hyway 56mm, skirt widths (exhaust side, at least...didn't measure intake because the piston ring end, not skirt-width, is limiting factor on intake-width...and exhaust size, when porting these, is basically a function of intake port since OEM spec is to essentially match the port areas but giving a 10degree duration advantage to intake-port)
JB'd intake floor will be ready to carve tomorrow, at which point I'll be putting Moto on my base gasket, spark plug & decomp plug and assembling everything (spark plug washers are crush-washers, single-use, I recently learned...thanks @John's Custom Saws!!), will be running at least a couple tanks with the older piston so the Hyway can be introduced once the ports / jug have had some time to wear-upon the older piston, will hopefully be back to report success at that point - and then swap over the other unit to a 56mm top end!!