Urgent: CBR600F2/F3 interchangeability?

[Marc Jaxa-Rozen]

After a nasty incident involving a misshapen exhaust valve and our CBR600F2's #3 piston, we're now looking for a new engine (the cylinder wall has at least a .020-deep gouge, with possibly more damage at BDC, and repairing it would require too much time and money). Does anyone know whether the F2 and F3 mounting points are identical? Since we'll be buying a scrapyard engine anyway, at least we could get something a bit more recent...

Thanks!

Marc Jaxa-Rozen
École Nationale d'Aérotechnique

[Marc Jaxa-Rozen]

After a nasty incident involving a misshapen exhaust valve and our CBR600F2's #3 piston, we're now looking for a new engine (the cylinder wall has at least a .020-deep gouge, with possibly more damage at BDC, and repairing it would require too much time and money). Does anyone know whether the F2 and F3 mounting points are identical? Since we'll be buying a scrapyard engine anyway, at least we could get something a bit more recent...

Thanks!

Marc Jaxa-Rozen
École Nationale d'Aérotechnique

[Denny Trimble]

I think the mounting points are the same, I've heard stories our team swapped an F2 and F3 in Detroit. The shift drum rotation is opposite, and it took them forever to figure out why the car wouldn't shift the way it was supposed to.

[Marc Jaxa-Rozen]

Denny,

OK, thanks. I remember reading something about F2/F3 compatibility on the old email list but this is one of those things you prefer to be 100% sure about http://fsae.com/groupee_common/emoticons/icon_smile.gif

Marc

[Scott Harsila]

To back up Denny, since I was there during the 2001 F2/F3 mayhem at comp, yes they are directly compatible except for the shifting order. You have to swap your shift cable from top to bottom or visa-versa. In our infinite wizdom(the typical comp frenzy fueled by gasoline and brake cleaner) we actually swapped the shift drum and forks from an F2 into an F3 to make the shift order work right without changing the shift cable mounting.

That is all I can remember about it, so take my advice with a grain of salt.

[Marc Jaxa-Rozen]

We're using a rigid linkage, so as long as the shift drum is dimensionally the same it wouldn't really be a problem. However, unless we find an F3 in really good shape we'll probably end up getting an F2, as the wrecked engine leaves us with a sizeable spare parts stockpile.

Marc
École Nationale d'Aérotechnique

[Scott Harsila]

Many F2 and F3 parts are exchangable, internal and external, don't ask me how I know. Something about a frankenstine motor in an old car.