Big Bore Reliability - Hick or anyone, any inputs?

Well, my mechanic-ing skills (or lack thereof) have once again cost me some downtime and money. I forgot to put oil in the damn thing and siezed the piston following a head gasket replacement. I was looking for the least expensive repair method and so far Eric Gorr big bore kit is slightly cheaper than stock part replacement. I researched the big bore topic on this board and the posts are sorta old when reliability data was suspect. I was wondering a few years later if the 444 big bore kit was reliable or not (assuming you put oil in). I went two years on my bike before the head gasket failed. The cylinder showed little to no wear when I originally had it apart for that repair. Based on that inspection I was hoping to get 4-5 years out of the stock cylinder/piston combo (I don't ride a whole lot). Any reported premature failures of parts due to big bore kits?

I was looking for the least expensive repair method and so far Eric Gorr big bore kit is slightly cheaper than stock part replacement.

Are you sure? A new barrel is only about $250…

I researched the big bore topic on this board and the posts are sorta old when reliability data was suspect. I was wondering a few years later if the 444 big bore kit was reliable or not (assuming you put oil in).

Don’t forget about coolant

I did not experience any reliability problems inherent with the big bore kit that I was aware of, although I did have lots of (unrelated) problems with that particular bike. As it turns out I must have gotten it very hot at some point because I discovered much later that my barrel had warped. The bike ran fine when I took it apart, but I sold the bored cylinder to another TTalk member who discovered the warpage.

Obviously the thinner cylinder walls may allow it to warp easier than one with a stock bore, but I would have to guess that in my case it was overheating that ruined my cylinder (I did get the bike pretty hot a few times that I can recall). I don’t have any real reason to try an overbore again, but I also don’t have any reason not to. When it did run, it ran well. The bigger piston could pull a gear taller almost everywhere.

BTW I still have two Cometic gasket kits and a 12.5:1 Wiseco 97 mm piston, all brand new, never used! :)

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