ALI EL-CHEAPO SNAKE
2.8cm = diameter at exhaust port outlet
63cm = left header length
61cm = right header length
3.7cm = diameter after merge
3.5cm = diameter mid-pipe section
4.5cm = diameter just before muffler
5.1cm = diameter muffler interface
I call this Ali exhaust "Snake" due to its multiple extra bends and curves compared to stock. It runs down
left side of bike and claims to be compatible with pre-gen, new-gen and 300 models. It's made from sand-blasted 304-stainless which gives nice matt-finish that's more tolerance of greasy fingers. Out of all exhausts, it has an actual down-size in diameter in mid-section after merge, going from 3.7cm to 3.5cm. This is done to generate slip-fit of rear-section.
It does have nice non-collector merge and conical transition to end-section. Nice final expanded section to fit directly into Ali universal mufflers with 5.1cm ID, so no adapter-cones or silly mid-pipe adapter pieces needed. Due to extra length, extra bends and step-down mid-section this is worse design of them all. No mid-pipe hanger since there's no hanger-tab on left side of engine anyway. Does come with O2-sensor bung, however, only samples exhaust from #1 runner only.