Rulebook question 775cc singles limit in D

So something built on a GP Chassis but no longer has a 2 stroke in it is no longer a GP machine?

 

huh?

 

There were ways to take the BMW F650 single up to 750cc.

 

If someone could afford a Moto2 or MotoGP CRT bike for club racing would those be considered GP bikes? I'm confused.

 

Got it. It just seemed odd without further explanation.

 

goodness, no. a Moto2 bike is a custom frame with a motor from a CBR600. and we know how slow those things are.

 

isnt the ktm moto3 bike a dirtbike motor?

 

It's got nothing to do with how fast or slow they are.
I'm just trying to nail down the definition of what is or isn't a GP bike. I seem to have had it wrong ever since I first got involved in club racing.

 

No, it's a purpose built evil thing IIRC.

 

i'm gonna run a destroked R6 565cc motor in a Moriwaki Moto2 chassis in Clubman!

(that'll be worth the money )

 

Wanna buy a 580?

 

"Formula" is custom chassis with production motors.
"GP" is purpose built motors in any chassis.

 

I race a 660 Yamaha out here on the left coast thats now over 700. It's the five valve motor that was in the MZ and the Raptor for some years. Mine is in a TZ 250 chassis. I know of a kit that will take these things out to something stupid like 850cc but it's for a quad that doesn't run sustained high rpm like we do.

That 690 is a sweet motor. I talked to Karsten as well about a framecrafters frame for one and he mentioned the geometry was kinda wonky for road racing. I saw a 125gp size custom framed job with a 690 in it ... that would be the weapon to have.

https://www.flickr.com/photos/82539428@N00/15955000456/

 

I have the vortex ecu. and had new maps loaded up. they can make any map you want. plus it can be adjusted + or - 10% either way.

 

Ate51

That's what my Scorpion wants to be when it grows up. Cool bike. Love the in n out sticker.

 

yeah, that statement confused the HELL outta me. I thought a GP bike was a bike that was not street legal and made for the one purpose of racing on the track. The MD250 is exactly that isn't it?

I always wondered why the MD250 was out on the D grid when I was racing it, and had any adult ridden it, and beat me in a real race (GNF type) I would have protested it. I may have no won but would have tried. I am guessing that Sean is calling a GP machine STRICTLY a Two stroke. But isn't the MD a 125 frame with a 250 wedged in?

4. SUPERSTOCK: There must be at least 1000 motorcycles available to riders, worldwide, per year and the machine must be generally available on the U.S. market with full EPA and DOT approval to qualify a machine for the Superstock categories. Proof of eligibility must be provided by the rider. Superstock machines are defined original motorcycle manufacturers’ equipment intended for use on public roads which are allowed to use an aftermarket or racing exhaust system instead of the stock exhaust system and other modifications as listed below. The decision regarding the legality of any machine entered in a Superstock class is the responsibility of the Chief Technical Inspector for the event in progress. The rider or sponsor of any machine is responsible for producing a service or owner’s manual with all part numbers, specifications and other material required to prove its legality. Legality will be determined based upon manufacturers’ specifications (or comparison of similar OEM parts) for the year, model and make of the machine entered.

 

Damn you!

 

There are no restrictions on Formula Chassis:

6. FORMULA 1, FORMULA 2, 125cc GRAND PRIX and Clubman (or any subsection of a class that specifies “Formula Rules”) Have no restrictions other than displacement, fuel limits as outlined in Chapter 8, and configuration as outlined below.

Only restrictions are those noted in the individual classes which primarily deal with engine configuration and size.

If there is a definition of what constitutes a GP bike in the rulebook I've never been able to find it.