GSXR450. Take a 600 and drop a cylinder

[thorn14]

http://feelthetrack.com/gsxr-450/

"1 â€" remove engine
2 â€" remove cylinder head
3 â€" remove all four valves from one cylinder (we use #2)
4 â€" clean the valve guides and fill with RTV silicon
5 â€" reinstall head and new head gasket
6 â€" reinstall engine
7 â€"  dyno tune
8 â€" go race!"

A 450 3 cylinder... kind of.

[RichD]

You'd lose less power if you put a bob weight on the crank and pitched the rod/piston/rings.
Ring drag is an exponential loss with rpm. 

[thorn14]

I think that's what the guys who race in the 450 class seriously do. It's an interesting alternative to the VFR and FZR 400's, along with whatever else race's in those classes.

[Triple J]

There's a class for this in AFM (club race org. near Dave Moss). It's billed as a cheaper and simpler way to go racing if I remember correctly.

A couple of years ago at a trackday at Miller I pitted with the Kiegwins track day instructor who was heavily involved with this effort in AFM. It sounded pretty easy and cool...and he was faster on his "450" than I was on my friend's RSV4!

[Spidey]

There's a class for this in AFM (club race org. near Dave Moss). It's billed as a cheaper and simpler way to go racing if I remember correctly.

Yup.  I've got pictures of them somewhere, but they basically just look like GSXRs.  There's been a long running discussion in the AFM about them, whether they make sense, whether they're financially viable, blah blah blah http://www.bayarearidersforum.com/forums/showthread.php?t=415111

Personally, I like the idea of race bike with a modern frame, suspension, brakes, etc. but without tire-ripping HP.  Dunno if a cripple fits the bill, but it's pretty close.

[thorn14]

Yeah, it definitely caught my eye with regards to AFM racing. I don't have the funds or time yet, but when I do, it's a class that sounds like it'd be fun.

[Spidey]

For bang for $ for AFM racing, FLAP (http://www.feellikeapro.com/) is a great program.  Race Ninjettes.  Really competitive racing, and by all accounts, a good group of folks.

[Triple J]

For bang for $ for AFM racing, FLAP (http://www.feellikeapro.com/) is a great program.  Race Ninjettes.  Really competitive racing, and by all accounts, a good group of folks.

That's a really cool idea!

Do they give out ear plugs too? Ninjas sound like SHIT! 

[Speeddog]

You'd lose less power if you put a bob weight on the crank and pitched the rod/piston/rings.
Ring drag is an exponential loss with rpm. 

Mmmmm, yeah, something like that.

Removing all the valves doesn't make much sense to me.
Other methods would rob less power, IMO.
But I've not done it, and not likely to either.

I imagine the sound is an acquired taste.

[Spidey]

That's a really cool idea!

Do they give out ear plugs too? Ninjas sound like SHIT! 

Yeah, it's a cool.  It's pretty much single-handedly filled the 250 grid.  The bikes come with exhausts.  So they sound like a refreshing, fibery, aftermarket dump, not a typical OEM shit.

Mmmmm, yeah, something like that.

Removing all the valves doesn't make much sense to me.
Other methods would rob less power, IMO.
But I've not done it, and not likely to either.

I imagine the sound is an acquired taste.

Mmmmm, yeah, something like that.

Removing all the valves doesn't make much sense to me.
Other methods would rob less power, IMO.
But I've not done it, and not likely to either.

The idea is to make it easy to do, and easy to reverse on the cheap, not to max out power.  If they wanted to max out power, they wouldn't be doing it with 10+ y/o bikes, or pointlessly carrying all the extra weight of a 4 cylinder 600 around.  Again, dunno that it's the solution (as racing always leads to HP wars), but you can buy an older 600 cheap, pull a coupla parts off and you've got a cripple.  Then you go out and bang fairings against other lunatics who thought it would be a good idea to depower a perfectly functional bike just to go racing.