| If you can't get the rear pipe as long as the front wouldn't having it made in a larger diameter to give it a equal volume do the job.
At least the exhaust only has to deal with two gas discharges for every two rotations of the crank (unless we're talking about my 620 lst Saturday at Snett, nothing another ECU set of Clocks and a key transponder couldn't fix), so has a bit more time to deal with them than a IL4 does.
Standard 600SS header pipes worked well on my class B bike when fitted with a decent can, put it up at the 52bhp mark.
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