Dirt bike engines in GP bikes?

What about doing the opposite? Take an RS125 power plant and graft it into an 85 or 125 dirt chassis as a motard from hell?

 

Thanks for all the info, guys. My original thought was to pick-up an Aprilia RS125 (derbi lookin' model) but they're pretty much street bikes (like my former 250). I thought since dirtbike engines need to be rebuilt so often, they must be in a high state of tune. I've never owned a dirtbike before so this is all just speculation.

If I could mount the dirtbike 125 engine in a Honda RS125 chassis, I wonder if it would run in the same group as the RSs & TZs or maybe at least faster than the Aprilia. From what you guys are saying, probably not.

Not that I could afford it but anyone know how the Derbi (former rookies cup bike) performs compared to the Hondas and Yams? They look pretty sweet.

 

Tdub,
That is what Stewart told me he had on his dyno. 52 he said is what Nobi or Jakes Aprilla put out( do not know if they were ever on Stu's dyno). I don't know. Just going by what I was told. He also said a good tuned stock RS 125 on his dyno puts out 40 HP.

 

Quick question, I'm 5'6 150lbs am I too big for a Morwaki 250?

 

Cajun,
I think you will fit, having said that, my son is only 105 and about 5'5'" now. He said he can tuck in on the Honda RS125 better, because the Moriwaki's tail section doesn't allow his rear end to slide back as much. If that was an issue, you could always figure out a way to slide the tail back a bit or put on the 125 tail section.

You can also mount up differnt rearsets to give more legroom. However, it looks like they might put your right foot to close to the exhaust so some fab work maybe required.

Tdub, how tall was Jake when he rode the Moriwaki last year?

Doug,
I thought you meant Honda RS125. I can see where an Aprilla 125 could make that kind of horsepower, although I don't know.

 

Thru the course of the season Jake went from 5'8" to 6'. He was about 5'10" in this pic and Indy, but he is just 125# now.

 

Really?

79 hp from a KX500? C'mon.....

 

Absolutely!

 

Tdub,

Great picture. Jake rode his tail off that weekend.

 

Yeh he did...would have been even better had I been more on top of things though.

 

Thanks, next time I'm at a race weekend and I see one, I will ask the owner if I could sit on it. I think it would be awesome to have one.

 

Where do you live/race, I'm presuming you were/are stationed in kandahar?

 

I'm in Kabul Now. Got 10 days left. I race in the South East.

 

We'll have Draik's 125 at all but one of the SE Races this year, I believe it has the same dimensions as the MW 250's. You are more than welcome to see if it fits you.

 

Thanks Man, I will make that RRR round in june for sure. Hope to see you guys there.

 

Hey bro, I think Palmer Kling rides a Moriwaki 250 as well. I will contact his dad to make sure they will be there. See you in a few days.

 

We will be there, and you are welcome to try the Moriwaki on for size. It sure is a fun little bike.

We have the opposite problem. My little one is barely able to reach the bars. The first few times he rode it we had to take the tank cover off so he could reach. He does appear to be hitting a growing spurt though.

 

Easy.

 

Awesome. I met you guys last year at the May Barber round. See you guys in June.


Dan we gotta do some Track days to get me tuned up for RRR

 

I love watching your son ride... And the relationship that you two have should make every Dad envious. It's espescially cool when he gets the mic from Jeff. Congrats!