Dirt bike engines in GP bikes?

HRC is claiming 35.5 kW (47hp) at the crank for the new NSR250. We achieved over 42rwhp from a CR250 motor with stock ignition and carb, and never went below the base gasket while using aftermarket parts that anyone can buy. Have not only RRed this motor but we are still running it in a dirttracker....with no issues. When I do rebuild it will get an aftermarket crank.
The 2 hotrods that ran the 2009 USGPRU season were not only very fast (ask Nobi) but very reliable as well (ask me).

 

so you outperform a 14kg lighter, and at least 10hp faster bike with that lawn moawer?
i say riding skills has a lot to do with it to then.

 

The NSF weighs 185# vs the HotRod MD at 192# ( no attempt at weight savings...still had the battery and 600 exhaust can on it))

The NSF has 47HP at the CRANK vs the HotRod at over 42hp at the rear wheel which puts them pretty damn close.

Jeesh! Maybe you should just stick to your 2 strokes cause this seems like it is just way over your head

 

when i say 14kg lighter and 10hp more, i mean a 125GP bike.
you should change rides with those aprilia's, i bet ya you guys finish more ahead then you already claim to do.

 

Yo Danny, Tdub, or any other hybrid builders; anyone have experience with a Cagiva Mito? I'm thinking a Yamaha 660 single (five valve if I can find one) would be a neat bike to build.

 

Talk to Tim Barker of Lapeer Mi. He is the man when it comes to the 660! His business now is primarily exhaust but he has alot of history with the 660.


http://www.barkersexhaust.com/

 

What difference does that make when there is a minimum weight limit??

You really should do your research...comments like this just make you look stupid

 

Hey Danny,

What failed on Garrett's hot rod back in 09 at either the USGPRU finals or WERA GNF? I really liked our Hotrod but had a failure that I think could be easily rectified and wondered if that is similar to what you had happen. I checked the valve clearances after every race weekend and they had not moved out of spec. and bike probably only had about 5 weekends on it. But at Miller in June she blew.

It ended up being the "high $" custom cam/springs/retainer kit. After tearing it apart I noticed the valve spring was shaving away the bottom of the Ferrara retainer. I called the vendor I bought the stuff from and he said, "Oh yea, we started having that problem with those titanium retainers and went back to steel and the problem has gone away". Too bad I wasn't connected enough to hear about it beforehand, or smart enough to look. I was banking on the fact that once my valves started to need adjustment, I would take everything apart to inspect. With steel retainers, I believe that would still be possible.

Other than the huge expense of replacing everything that broke in one swoop, I really liked the hotrod. Tyler actually liked both, but preferred riding the 125. He liked the feeling of it coming on the pipe and the challenge of riding a 2 stroke.

 

It broke a piston that was very close to its scheduled replacement anyway, the piston cracked through the dome parallel with the wrist pin causing no other damage. It was replaced on Sunday morning and Garrett won all of his races that day.

The titanium retainers wear and should be checked regularly, polishing the ends of the springs helps a lot. I prefer the steel seats as to me there is no benefit to the titanium ones.

 

Have you seen any of his comments that made you think he wasn't stupid?

 

Thanks for the info. What was your piston replacement schedule? I think the stock Moriwaki manual called for quite a long time like between replacements, nothing like the 300 miles on the RS125. I presume yours was high compression like mine was, so it may have been on a different replacement schedule.

 

We were using a Carillo in that thing and looking at it every 600 miles and replacing it every 1200, the one that broke failed at over 1000 miles, but I think it was the victim of a rushed downshift. Pistons don't normally fail in that manner when under load. JMO

 

so, to beat a 125 2t they first have to add led on it?........pfffffffffffffff
after giving 2x the displacement, and wheight changes they can keep up, and you are saying that i look stupid......

 

Hey Anand,

These guys just race with the rules given, they don't write the rules. They are smart enough to figure out how to win under the rule set given. You are arguing with them about something they have no control over, so how do you think that makes you look?

 

i did not start saying that anybody looks stupid for some reason or another.
i never start this type of arguing by my self, anybody can correct in me a normal way, or explaining me how the real situation is. if if not... i will play along
so what i statet is true then, and only with some adjustments of rules the lawn moawers can keep up, or beat the 125's

 

Which one is the lawn mower? I grew up with a lawn boy, it sounded like the chain saw, the weed wacker and a RS125.

 

lol, only the chainsaw was the 2t in our lawn, the moawer was a honda 4t

 

Just found this article browsing the classifieds. Seems pretty badass

450 Super Single