Supercharged CBR250 build

See cars and bikes being built for the salt

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RGV
Posts: 708
Joined: Sun Feb 06, 2011 9:17 pm
Location: Mid Murray Mallee

Re: Supercharged CBR250 build

Post by RGV »

6 plugs Tiny? You holding out on us?

Ya running any top end lube?

Dave

Last Minute Racing
DLRA #928

2010 MPS/G 250 118 MPH
2011 Washed Out
2012 Washed Out
2013 MPS/G 250 131 MPH (RECORD)
2014 MPS/G 250 140 MPH (RECORD)
2015 MPS/F 250 DNF
2016 MPS/F 250 114 MPH (RECORD)
2017 MPS/F 250 DNF
Stayt`ie
Posts: 1041
Joined: Fri May 13, 2005 11:47 pm
Location: Mackay

Re: Supercharged CBR250 build

Post by Stayt`ie »

from what i can see, for an Alky plug their lookin pretty safe for lsr, 8) , 9's or 10's, :?:

can you post up a closeup side shot of the electrode, so i can have a look at ya timing, :wink: ,,
First Australian to ride a motorcycle over 200mph at Bonneville,,,
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gennyshovel
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Joined: Tue Mar 29, 2005 10:10 am
Location: Broken Hill

Re: Supercharged CBR250 build

Post by gennyshovel »

Stayt`ie wrote: can you post up a closeup side shot of the electrode, so i can have a look at ya timing, :wink: ,,
Nope, for 2 reasons Ronny, #1 is my camera ain't that good, and # the timing cant be changed mate.
I'll fatten up the pilot 'cos it's near impossible to start, A/F 6ish, no changes when pilot air screw is either closed, or out 3 turns (gas pilot is #45, there's a #90 in it now, will fit a #100 next, maybe drill the orifice 11 tho bigger if needed, go a bit bigger on needle yet to get rid if the miss (never had a miss before, but it's been filthy rich, not according to the innovate LM1 & bosch 4.2 combo, which has been telling lean lies
Tiny DLRA# 484
Postiebike Racing , created & funded by TwoBob Engineering
Stayt`ie
Posts: 1041
Joined: Fri May 13, 2005 11:47 pm
Location: Mackay

Re: Supercharged CBR250 build

Post by Stayt`ie »

sweet, dont be wasting ya money on cameras mate, :lol: ,,

6.45 Alky equates to 14.7 Gasoline, + or - ,, most fellas(fast, naturally aspirated) i have spoken with at Bonneville target a/f's in the 12.7-8 range on Gasoline, this equates to around 5.6(fatish) with Alky, :D ,, my bike runs its best a little fatter with a/f in the low 5's,, always keep in mind that most if not all of the information out there is based on hemi head motors, pentroofs, i have found, like more juice, :wink: ,,,
First Australian to ride a motorcycle over 200mph at Bonneville,,,
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gennyshovel
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Location: Broken Hill

Re: Supercharged CBR250 build

Post by gennyshovel »

I'm almost ready for 2015, just need to fatten up a bit more (any suggestions Dr Goggles ?) :roll:


http://youtu.be/5xLWzshRkwY (the sound of today's test'n'flog)



Image

That was easy, NOT . :oops:
Tiny DLRA# 484
Postiebike Racing , created & funded by TwoBob Engineering
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AuotonomousRX
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Location: Eyre Peninsula SA

Re: Supercharged CBR250 build

Post by AuotonomousRX »

Hey Tiny

Good to see your are making head way 8)

did the Power Jet you fitted make any difference to the Tune?

Pete :D
Still trying to decide if I am a procrastinator

Pete :?
DLRA #866
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gennyshovel
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Joined: Tue Mar 29, 2005 10:10 am
Location: Broken Hill

Re: Supercharged CBR250 build

Post by gennyshovel »

It's working !
Last jet change went from max Power Jet and #620 main, to 3 turns out & #640 main, the plugs look a bit cooler after the last run, next run will be with #680 main, same 3 turns & hopefully, the plugs will look like new when pulled out, if so, I'll lean off with the Power Jet until I get some heat into 'em,then throw new plugs in and fine tune the color out, then I'll have a tune to avoid and get a few trips down the salt before adding more boost :shock: ?
Tiny DLRA# 484
Postiebike Racing , created & funded by TwoBob Engineering
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AuotonomousRX
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Location: Eyre Peninsula SA

Re: Supercharged CBR250 build

Post by AuotonomousRX »

Good news Tiny 8)

Pete :D
Still trying to decide if I am a procrastinator

Pete :?
DLRA #866
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gennyshovel
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Location: Broken Hill

Re: Supercharged CBR250 build

Post by gennyshovel »

The last chore was to fit a 12v normally closed solenoid to turn off the fuel supply when either the kill switch, or the lanyard switch operate, I discovered a while back that fuel still trickles thru the pump even when it is turned off, not much, but still too much, this solves that problem.
Fitting the fire sleeve was a pitta, but all unswitched hoses are protected as per the rule, and fuel can be turned off without my hands moving from the 'bars
Image

Image

The carb in the pics is the gas carb, the fuel version will be used at the lake & the original fuel spigot is blocked, not as this one is, but permanently
Having a gas carb allows me to start the engine any time, without the pain of flushing & purging methanol when I'm finished fiddling
Tiny DLRA# 484
Postiebike Racing , created & funded by TwoBob Engineering
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BONES
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Location: Killara Sydney

Re: Supercharged CBR250 build

Post by BONES »

Hey Tiny
I still have that spare piston
Bones
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gennyshovel
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Location: Broken Hill

Re: Supercharged CBR250 build

Post by gennyshovel »

Best you put it in your favorite stubby holder Bones, that way it'll make it to the lake next year :wink:
Tiny DLRA# 484
Postiebike Racing , created & funded by TwoBob Engineering
momec3
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Joined: Tue Mar 01, 2011 10:36 pm
Location: Cedar Grove Qld

Re: Supercharged CBR250 build

Post by momec3 »

Tiny, when fitting fire sleeve shove the air nozzle in one end and lightly inflate as you drag along. Sometimes this helps install.
Chris
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gennyshovel
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Re: Supercharged CBR250 build

Post by gennyshovel »

I guess I should update Laslo's illness post Speedweek 2016,
It died
Image

Image

Image

The good news is,,it's nearly ready to do it again, without carnage next time ?
Tiny
Tiny DLRA# 484
Postiebike Racing , created & funded by TwoBob Engineering
harky
Posts: 252
Joined: Fri Feb 09, 2007 9:03 am
Location: Adelaide

Re: Supercharged CBR250 build

Post by harky »

you call that "mechanical Art " we all have too much of it
does anyone else find it "artistic "
expensive but interesting
I have a conrod from a F5000 , that hit a flag marshall @ Phillip Island , grazed his leg !!!!!
it was from a race car I was working on ------- he came up to us after the event to ask if we wanted it back !!!!!
the block was like swiss cheese ---------- I told them it was past its "hours" useby date !!!
It was a repco holden F5000 engine ---- be a rare item now
harky
harky
DLRA #643
so far 120mph for$2000---imagine how fast I can go for $20,000
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RGV
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Location: Mid Murray Mallee

Re: Supercharged CBR250 build

Post by RGV »

Bloody hell Tiny, I got away pretty lightly I would say. Thats a mess.

Dave

Last Minute Racing
DLRA #928

2010 MPS/G 250 118 MPH
2011 Washed Out
2012 Washed Out
2013 MPS/G 250 131 MPH (RECORD)
2014 MPS/G 250 140 MPH (RECORD)
2015 MPS/F 250 DNF
2016 MPS/F 250 114 MPH (RECORD)
2017 MPS/F 250 DNF
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