A/G 125 class build

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god of speed
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Joined: Wed Dec 22, 2010 9:58 pm
Location: melbourne

A/G 125 class build

Post by god of speed »

Greetings,

i am aspiring to set a record in the A/G motorcycle class with a kawasaki kr250 and aprilia 125 engine. my question is in relation to wheels. should i go spoked for low weight or cast alloy for longevity? 16/17/18"? as wide as possible for grip or as thin as possible for less resistance?

what do people normally run? some feedback from a voice of experience would be appreciated.

Thanks in advance

Charlie
Last edited by god of speed on Wed May 02, 2012 12:27 pm, edited 2 times in total.
- Charlie
'Overall happiness is directly proportional to the increasing distance between the front wheel and the ground.'
'The God of Speed' - 125cc Lakes Racer - www.thegodofspeedproject.com
'85 XL600R-L-M-PDGSAZ - Rest in pieces
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RGV
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Location: Mid Murray Mallee

Re: MPS/G 125 class build

Post by RGV »

Hi Charlie welcome aboard.
Weight isnt a problem, its actually better to be heavy (up to a point) mags are my choice, wouldnt like to see what the salt would do to a spoked wheel if it wasnt very well maintained.
The more streamlined the better so a small front tire, and you shouldnt have traction problems so i wouldnt go any bigger than standard on the rear.
I run an RGV250 and use standard size tires with as much tread down the center as i can get, eg: http://www.bridgestone.com/products/mot ... /bt45.html

Long Live 2 Strokes.

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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god of speed
Posts: 58
Joined: Wed Dec 22, 2010 9:58 pm
Location: melbourne

Re: MPS/G 125 class build

Post by god of speed »

hey thanks for the input, ive found a ninja 250 front end and zzr250 rear i might use, they look pretty light and not too wide.

another question, are we allowed to use coolant in the bikes or does it need to be water, i was hoping to actually use alcohol mixture for good cooling properties.

i still havent actually found an rg250 frame yet, i think ill post a wanted ad!
- Charlie
'Overall happiness is directly proportional to the increasing distance between the front wheel and the ground.'
'The God of Speed' - 125cc Lakes Racer - www.thegodofspeedproject.com
'85 XL600R-L-M-PDGSAZ - Rest in pieces
momec3
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Location: Cedar Grove Qld

Re: MPS/G 125 class build

Post by momec3 »

G'Day Charlie welcome aboard.
Coolant car or bike I would like you to look at Redline Water Wetta. Does not harm the enviroment and cools better than anything else on the market. Google it and form your own opinion. Its mandatory at Bonneville.

Chris
Chris
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god of speed
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Location: melbourne

Re: MPS/G 125 class build

Post by god of speed »

Hey thanks chris, ill look into it, i dont like the idea of alcohol in a crash being spilt over my red hot engine.

any other tips that are obvious to you but not to s salt noob
- Charlie
'Overall happiness is directly proportional to the increasing distance between the front wheel and the ground.'
'The God of Speed' - 125cc Lakes Racer - www.thegodofspeedproject.com
'85 XL600R-L-M-PDGSAZ - Rest in pieces
momec3
Posts: 780
Joined: Tue Mar 01, 2011 10:36 pm
Location: Cedar Grove Qld

Re: MPS/G 125 class build

Post by momec3 »

"any other tips that are obvious to you"

Bring plenty of beer!
Chris
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god of speed
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Re: MPS/G 125 class build

Post by god of speed »

well thats a given! haha
- Charlie
'Overall happiness is directly proportional to the increasing distance between the front wheel and the ground.'
'The God of Speed' - 125cc Lakes Racer - www.thegodofspeedproject.com
'85 XL600R-L-M-PDGSAZ - Rest in pieces
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god of speed
Posts: 58
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Location: melbourne

Re: MPS/G 125 class build

Post by god of speed »

do we need to run filters on the intakes or is the air clean enough on the salt?
- Charlie
'Overall happiness is directly proportional to the increasing distance between the front wheel and the ground.'
'The God of Speed' - 125cc Lakes Racer - www.thegodofspeedproject.com
'85 XL600R-L-M-PDGSAZ - Rest in pieces
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RGV
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Location: Mid Murray Mallee

Re: MPS/G 125 class build

Post by RGV »

I run a course filter more to settle the air in the air box than filter it.

Its pretty clean out there but it all depends on weather your carby can suck flicked up salt or not.

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
Dr Goggles
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Location: Right behind you Chief !

Re: MPS/G 125 class build

Post by Dr Goggles »

word of warning for the first time player.

Salt attracts water .That last bit that gets sucked into the intake and then ends up in the manifold, siting on top of a piston or resting on top of the valve will drag water out of the air and start chewing away moments after you shut the thing off..........residual salt from a spin corroded the valve seats on the Orange EL Falc of Daryl Chalmers one year , meant a whole reco of the head....

we haven't up until now but I'm planning on some sort of way of fitting a coarse filter to the tank......other than that a bit of a backyard "de-coke" probably never hurts either..
...few understand what I'm trying to do , but they vastly outnumber those who understand why..
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god of speed
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Location: melbourne

Re: MPS/G 125 class build

Post by god of speed »

a coarse filter on the tank?
- Charlie
'Overall happiness is directly proportional to the increasing distance between the front wheel and the ground.'
'The God of Speed' - 125cc Lakes Racer - www.thegodofspeedproject.com
'85 XL600R-L-M-PDGSAZ - Rest in pieces
Dr Goggles
Posts: 1315
Joined: Tue Jul 05, 2005 11:23 pm
Location: Right behind you Chief !

Re: MPS/G 125 class build

Post by Dr Goggles »

Sorry, short for bellytank....

Image
...few understand what I'm trying to do , but they vastly outnumber those who understand why..
momec3
Posts: 780
Joined: Tue Mar 01, 2011 10:36 pm
Location: Cedar Grove Qld

Re: MPS/G 125 class build

Post by momec3 »

The blessed salt is in the wonderful atmosphere at the beautiful lake and filter or no filter it does get in.
I tend to drown the running motor with CRC when it is both finished speedweek then when it gets home. The shit gets everywhere and if your not going to strip it at home then dose it with LOTS of CRC.

No I don't run a filter..........

Chris
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grumm441
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Re: MPS/G 125 class build

Post by grumm441 »

Hey Charlie
Why don't you just run a complete Aprilia RS125
They have a pretty good shape and they are not that expensive
G
They make it
I make it work
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god of speed
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Location: melbourne

Re: MPS/G 125 class build

Post by god of speed »

grumm441 wrote:Hey Charlie
Why don't you just run a complete Aprilia RS125
They have a pretty good shape and they are not that expensive
G
id just rather build my own bike, not just buy one, strip some stuff of it and go. this is more a learning excersize to increase experience in engineering and motorcycle tuning. the record is awesome but not that important to me. i just like the idea of building something myself that is completely unique and for one purpose.

besides the aprilia is over engineered, bulky twin spar frame with heavy plastic fairings, is not what i want. i am going for much less weight plus im going for about 30-40kmh faster than the aprilia top speed anyway.

i dont really call $4-5k cheap for a mid 90s 125. infact ive just got a kawasaki kr250 double cradle box aluminium frame for $300. my engine was 500, exhaust will be 600, plus engine mods and parts. it might add up to the same as a standard aprilia but it will be a purpose built salt machine instead of a road bike with rossi's gp stickers.

next question, does everyone who runs in the 'pump gas' class (commercially available) run the 10% ethanol fuel?
- Charlie
'Overall happiness is directly proportional to the increasing distance between the front wheel and the ground.'
'The God of Speed' - 125cc Lakes Racer - www.thegodofspeedproject.com
'85 XL600R-L-M-PDGSAZ - Rest in pieces
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