I'm looking for input from YZF 250 owners that may have direct experience of the relative merits
of Eric Gorr's 267 overbore or the Thumper Racing 290 overbore.
I know this subject has been touched on before in the broader spectrum of overall performance
upgrades for the bike, but I'd like to hear more about these specific modifications. I'm looking for
an overall power gain, but with an emphasis on the low to mid-range.
Also, I've heard that Thumper uses a steel sleeve in their kit. Is this true and if so, is there really
as big a drawback to that as one would logically assume, or does it work OK?
of Eric Gorr's 267 overbore or the Thumper Racing 290 overbore.
I know this subject has been touched on before in the broader spectrum of overall performance
upgrades for the bike, but I'd like to hear more about these specific modifications. I'm looking for
an overall power gain, but with an emphasis on the low to mid-range.
Also, I've heard that Thumper uses a steel sleeve in their kit. Is this true and if so, is there really
as big a drawback to that as one would logically assume, or does it work OK?