It lives

See cars and bikes being built for the salt

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gennyshovel
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Joined: Tue Mar 29, 2005 10:10 am
Location: Broken Hill

Re: It lives

Post by gennyshovel »

AuotonomousRX wrote: then again SC is always an option :wink:

Pete :D
CYA there :D :D :D
Tiny DLRA# 484
Postiebike Racing , created & funded by TwoBob Engineering
grumm441
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Re: It lives

Post by grumm441 »

dplecko wrote:Image
Variable length expansion chamber. Nice.
Yep. they do some stuff to those Lambretta's
G
They make it
I make it work
internetscooter
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Re: It lives

Post by internetscooter »

grumm441 wrote:
dplecko wrote:
Variable length expansion chamber. Nice.
Yep. they do some stuff to those Lambretta's
G
This guy did 136mph with only 4 gears - hence the need for a wide power band
Paul
---
DLRA #647
89.664 mph (aiming for 100mph+)
www.vespalabs.org
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dplecko
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Re: It lives

Post by dplecko »

internetscooter wrote: This guy did 136mph with only 4 gears - hence the need for a wide power band
How many cc?
internetscooter
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Re: It lives

Post by internetscooter »

dplecko wrote:
internetscooter wrote: This guy did 136mph with only 4 gears - hence the need for a wide power band
How many cc?
225cc with meth I think
Paul
---
DLRA #647
89.664 mph (aiming for 100mph+)
www.vespalabs.org
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RGV
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Joined: Sun Feb 06, 2011 9:17 pm
Location: Mid Murray Mallee

Re: It lives

Post by RGV »

First start on Methanol today. Fitted a pair of 975 (2.7mm) mains, 2.5 x larger than my petrol mains, along with some other big stuff and gave it a kick. Still on petrol ignition timing and compression but sounds nice and crisp. Will make a few adjustments and see how it goes. Smells great too. And its louder too I think. :D

Im running it on http://www.penriteoil.com.au/products.p ... oducts=440 that AuotonomousRX (AKA Salt Peter) was kind enough to give me a ltr. to try.

Click for a short video.

Image

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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gennyshovel
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Joined: Tue Mar 29, 2005 10:10 am
Location: Broken Hill

Re: It lives

Post by gennyshovel »

Make sure the needle jet is larger than the main Dave (orifice size)
I worked out the cross section area of the needle (A) (parallel part), then the cross section of the needle jet area(B), subtracted A from B with stock jetting, then worked out what size number drill I needed to increase the A - B by 2.2
A vintage MX guy mentioned to me once the main jet needs to be .001" smaller than the needle jet ? with methanol.
Remember all circuits have an influence on the main, fuel passes thru pilot even when at WOT
Tiny
Tiny DLRA# 484
Postiebike Racing , created & funded by TwoBob Engineering
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RGV
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Re: It lives

Post by RGV »

Thanx Tiny, its a steep learning curve ATM. Ive drilled out the needle jet to 3mm, jet size 1200, and lifted the needle to its max rich setting. I bought some methanol needles but they ended up being from a bigger carby so ill keep looking for some for mine. I havnt enlarged the idle circuit yet just screwed the air jet in so its 1/2 turn out instead of the original 2 1/2. Float level is set to max. height.

The difference between main and needle jet is 0.3mm (0.0118")

Because im drilling my jets I dont expect them to flow what a set of original Mikuni jets would so the numbers are just for reference.

Still need to check my fuel flow, think ill need to have 2 lts a minute min. and work out a fuel cutoff. I was running a fuel pump but cant with this setup.

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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AuotonomousRX
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Location: Eyre Peninsula SA

Re: It lives

Post by AuotonomousRX »

Onward and Upward Dave

Pete
Still trying to decide if I am a procrastinator

Pete :?
DLRA #866
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AuotonomousRX
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Location: Eyre Peninsula SA

Re: It lives

Post by AuotonomousRX »

Dave what Needle # are in those Carbs?

Pete
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: It lives

Post by gennyshovel »

It seems your onto it Dave
Gaybay # 291036472490 is in charge of my fuel shutoff next year
Tiny DLRA# 484
Postiebike Racing , created & funded by TwoBob Engineering
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RGV
Posts: 708
Joined: Sun Feb 06, 2011 9:17 pm
Location: Mid Murray Mallee

Re: It lives

Post by RGV »

AuotonomousRX wrote:Dave what Needle # are in those Carbs?

Pete
Not those Meth ones, ill go have a look. 6DHN44 fitted now. They are the ones that came with the carbs.

Thanx Tiny ill have a look at them.

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

Re: It lives

Post by RGV »

Im having trouble finding my needle. They came with the carbs (VM38) I bought off evilbay USA. They are off a 550 cc twin 2 stroke snow mobile so might be specific.

6DH4 is lean yet 6DH3 is rich with 6DH2 in the middle. :roll: Im confused. Either way I think ill just get a couple of rich one's and give them a try.

Image

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

Re: It lives

Post by RGV »

Found a bit of info on a "Skidoo" sight. This is a copy of it.

http://www.dootalk.com/forums/topic/181 ... t-needles/

"Note that this is for mikuni needles only!!!

We can talk of the 6EHY2-59 needle.

The first number indicates which serie the needle belongs to. Different carbs uses different needles.
In this case # 6 which is TMX carbs

The letters that follows describes the angle of taper.
In this case "EHY" which indicates that this is a three taper needle. The angle increses by alphabetical order. E is less then H and H is less than Y. If there are only on letter the needle just has a straight taper. If two letters then 2 tapers.

The number following the letters is a factory identification number related to their production.
In this case #2. There can be more then one "6EHY" needles but with different diameter and taper point.

The last two numbers is for knowing how rich or lean a needle is.
In this case "-59" If you would like a leaner needle with the same taper you can use a 6EHY2-60 or if you want a richer needle 6EHY2-58

There can also be another number. It could be recommended to set the clip in the third notch. This needle would then be 6EHY2-59-3. You often see this number if reading a service or race manual from doo. The numbers are always counted from the top. # 1 is closest to the end of the needle and is the leanes setting, #5 is the richest setting.

Hope this helps <_< "

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

Re: It lives

Post by RGV »

Went to Ian Williams Karts today, our Mikuni dealer, and bought some needles. He didnt have my first choice, 6DP10 so had to take the second richest 6DP1. Thats it for the carbs I think. Ill fit them and start playing with the timing.

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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