250 four stroke breaks 130 mph

[dr j]

Thanks everyone for the congratulations and coments.  I got home late last night and had to work all day today to earn the money to be able fill the Nitrous bottles. 
It was a great meet for my red and white Honda with the CRF250R single cylinder 4-stroke motocross engine.  I chronicled here on LR.com the first Nitrous experiences last September and the follow-up runs in October.  Then I had the honor of being interviewed by Bill Hoddinott for Bonneville Racing News and thanks to the outstanding photographic skills of David Whealon I got the cover shot last issue.
Over the winter all I did was confirm the Nitrous jetting and the resulting power on the dyno.  It was exactly what Trevor Langfield of Wizards of NOS (http://www.noswizard.com/) predicted as the 30 jet indeed added 15hp.  He has not steered me wrong yet.
Saturday morning I bumped one of my early naked records on just the motor.  Then Saturday afternoon I put the front fairing on and slid the NOS bottle into the tail section bottle holder.  I made four NOS runs and just incrementally pushed the "little red button" earlier each time until I was using it in 4th a little and almost all of 5th gear.  No more acceleration at the trap had me up to 129.8mph by the end and all 4 runs surpassed my prior fastest of 126.6!
So overnight I thought about it and since the engine was still sounding sweet of course I changed to a bigger matched set of jets to give me 17.5hp of NOS.  Luckily the WON system has the jets at the pulsoids (solenoids) so easy to access.  Sunday I then made three more runs over a 90 minute span and they were 131.6, 130, and finally the 131.8mph on what felt like a perfect run!  Engine was still purring so I put it away to live another day. 

[roadracer]

I'm a little late with it, but that was an awesome run for you.  Keep it up.  Never know where you will end up.

[dr j]

Big news in the 250cc world!!!
     Dr J and his red and white altered 250 Honda broke the 130mph barrier with an outstanding 131.8mph run and a lot a number of other runs over 130 . Big congratulations 

DAEM,,my build isn't even close to firing up , and the stakes just grew by 11 mph !
Well done Dr J !

Tiny, what are you building down under?

Great Doc J Is the Parilla coming in June?

Ken, no Parilla in June, sorry.  I am shooting for September for it's engine rebuild outing.  Too much work and farm stuff this spring.  I will be back with my Honda though.  But will you be there I hope?

[generatorshovel]

[[/quote]

Tiny, what are you building down under?

Im attempting a supercharged fuel Honda CBR250R 4 cyl 250 slotted into a raked VT250 chassis (used last year by a friend's son in M/F 175, it'll be A this time 'round) using the CBR forks , wheels and swingarm, naked at 1st.
The cost is already blowing out my meagre budget, 1 1/4 SS tube for the intake alone looks like costing an arm and a leg,the original plan was to use the CBR frame, but I'd look like a dog humping a cricket ball on it,,,, and then I need the cams reground, any camshaft companies come to mind ?
I'm also still working on my aps-F/175 honda "postie bike" trying to wrap it up in a good (hopefully) aero package after filling the engine with new bits.
Tiny

[dr j]

Tiny, that's a really cool idea.  I wish we had the old CBR 250 engines to play with here in the states.  It makes me drool with envy.  I like the idea of the supercharger too.  I know that putting a turbo on my single cylinder 4stroke 250cc will not generate frequent enough exhaust power pulses to spool up.  But I'm still considering it as a "learning about turbos" exercise.
Good luck with your build.  Will you bring it to Bonneville in 2012 or stay at Lake Gairdner?

[generatorshovel]

Consider this build as another learning exercise for me Dr j , I'm entering the unknown zone here , and , as usual, I'll follow my thoughts and "have a go"
I doubt it will be ready for 2012, and definately no bonneville appearance in the near future.
Who knows , the engine may not agree with my plans, and spread its innards out early in the "test" rides
Tiny

[racer x]

All us 250 guys are in uncharted territory. Seldom Seen Slim blazed the first trail with his 250 Turbo. These are the golden years of 250 four stroke racing and just so much fun. I will be down there with you as soon as I can .

[Stan Back]

I expect TV coverage any day now.

[generatorshovel]

Hi again, there's been a lot of water under the bridge since I last posted (literally) , I nearly made it to lake Gairdner with the 250, and the DLRA speed trials were nearly on.
Progress was halted  by an oil leak, caused by parking the 250 too close to the 'ol Harley I think 
It had nothing to do with trying to control 70 PSI oil pressure with 7 PSI rated seals, I'm sure 
Hopefully,,by the time the Aussy speedweek is rescheduled,,I'll be ready (or the honda has given birth to an external conrod?}
I hope this link of the initial startup works

I think racer X will relate to the eardrum damage it has caused me 

[Milwaukee Midget]

Oh, yeah, just click on the pic.  Very evil sounding 2fitty. 

[wobblywalrus]

That sounded like a four cylinder one.  What engine is it?

[RacerX9623]

That's a four cylinder Honda 250 with a supercharger.   GREAT JOB guys . It sounds like beautiful music to me,  

[dr j]

Tiny,
Wow what a sound!!  I know my single cylinder CRF250R engine sounded nothing like that.  It was just a thump, thump, thump.  What a smooth purring yours does until it roars.  Like Midget says it does sound evil.  Beautiful supercharger addition too. Bummer you couldn't give it a run.  When is your next target?
By the way my Honda now sounds like a pesky mosquito as I replaced the 250-4stroke with a 125cc 2 stroke engine last summer. It has the same horsepower as my 250/4.   That's so I can head to BUB2012 where they don't care how many strokes per spark, they just care about stroke x Pi R squared.  But I will sometime go back to my 250/4. 

[debgeo]

Congratulations!!!!! Any idea of how much HP you are producing  before nitrous?

[generatorshovel]

Tiny,
  I know my single cylinder CRF250R engine sounded nothing like that.  It was just a thump, thump, thump. 
 Bummer you couldn't give it a run.  When is your next target?
   

Doc J, thanks for your interest.
My "other" bike thumps also.

Then purrs
http://www.youtube.com/watch?v=Uh6mtzR9Yr4&feature=channel
There is a LOT of work involved in setting another date for the DLRA event, there's a salt inspection happening now, and rumours of a possible  date sometime in May, or late Sept ?
My initial goal with the 250 is to better the "other" cbr250 record of 121.777 (MPSG-250), although I'll be in ABF-250, I'd feel a bit stupid if I can't do 125, but,,,lol

One day I'll get the 175 up to the "ton", but I'll need to finish the fairing 1st.