Ktm390
- Thread starter kxmike
- Start date
twistybits
Well-known member
Trust me, you do not want to enter 250 prod on a 390, despite being legal, unless you like being very unpopular. It's basically the only refuge for people who want to have fun with their legacy prod 250s. Hopefully rules will be fixed for next year to make this a non-issue.
There's plenty of other classes for the 390 to run in, against equally competitive machines. Note that there's a big difference between a street 390 and a 390 cup, due to the suspension difference, and the cup version not being sold "for the street" ("production motorcycles shall be limited to those manufactured for street use in the U.S.A"). There was an amendment that allows the 390 cup, *in cup tune* (meaning 38hp or whatever the detune was) to run in prod, however, you can't go do a dyno tune on your 390 cup and then enter 350 prod. It's kind of confusing.
For 250 superbike I have no idea, in theory I guess the bike is not sold for the street, however, the differences from the street version falls into what would be considered Superbike legal, not sure how to interpret that.
I'm trying to sniff the market for a street (non-cup) 390 myself, and would probably run it in:
FIII
350 Prod
250SB
Lightweight Twins
450SB
There's plenty of other classes for the 390 to run in, against equally competitive machines. Note that there's a big difference between a street 390 and a 390 cup, due to the suspension difference, and the cup version not being sold "for the street" ("production motorcycles shall be limited to those manufactured for street use in the U.S.A"). There was an amendment that allows the 390 cup, *in cup tune* (meaning 38hp or whatever the detune was) to run in prod, however, you can't go do a dyno tune on your 390 cup and then enter 350 prod. It's kind of confusing.
For 250 superbike I have no idea, in theory I guess the bike is not sold for the street, however, the differences from the street version falls into what would be considered Superbike legal, not sure how to interpret that.
I'm trying to sniff the market for a street (non-cup) 390 myself, and would probably run it in:
FIII
350 Prod
250SB
Lightweight Twins
450SB
Shaggy
Zoinks!!!!
Wouldn't a 390 get absolutely slaughtered in 450SB? The 450 cripples are putting down 80+hp last I checked. Seems like a serious disadvantage for the KTM on any track not named Sears Point.
twistybits
Well-known member
Yes, but there's usually a bunch of 300-class bikes entering, enough for some entertainment and race practice. Though as a novice I think I beat an actual 450 at least once
artymattonbarf
Well-known member
Thanks for sharing this info, I was also curious.
Just to clarify, the "de-tune" of a rc390 Cup bike consists of a small piece of metal (you can easily unscrew) that limits the throttle opening to ~70-80% that sits right next to the throttle stop. No need to tune again, just add or remove according to your class needs.
Matt
thedub
Octane Socks
Both production and superbike classes are limited to those motorcycles manufactured for street use (rule 9.1.1 & 9.2.1). Isn't your NSF250R a purpose built race bike? Then it's only legal for Formula classes.
Superbike rule 6.1.2b states that 4 stroke singles and twins can be built to either Superbike or Formula rules.
So, the NSF250R is currently legal for 250 SB. Up to 450cc singles built to formula rules are also allowed since singes can run down a class. That said, there is a movement afoot to remove this formula allowance from the superbike rules.
Great riding this weekend, 2wls4ever...you were absolutely flying on that NSF.
thedub
Octane Socks
TIL
Gawernator
Watchdog Armory
Who had that yellowish RS250R at Sonoma on Saturday? He kept getting off the pipe!!
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