Do i need to run my bike with race fuel?

yvaillancourt371
Hi guys, i need your help. I am build a kx250f 2013 for mx and i have couple question that i need answer.

This is my setup:
- ported head with copper valve seat (5 angles)
- Pro-Circuit camshaft
- kibblewhite titanium racing valve spring kit
- delwest titanium valves flat face (intake&exhaust)
- stock throttle body with stock injector
- wiseco 14:5:1 piston with DLC wrist pin
- Pro-Circuit ti-6 full exhaust
- stock oem crankshaft
- full polished transmission
- hinson complete clutch
- Evans coolant .....
- Shell rotella t4 15w40

My big question is , am i need to run with race fuel ? If it's mandatory which fuel should i use? Vp , sunoco.

2nd question: May i compensate the lack of octane with octane booster like Torco accelerator ? The best pump gas that we have here is 94 octane but he have approx 5% of ethanol inside.

3rd question: do anybody find a weak point To my build and have any advise for me?

I am building it for fun, i'm not an expert. I ride here in Montréal canada at sea level .

Thank's in advanced.


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adam8781
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adam8781 2/20/2020 9:56pm
2/20/2020 9:56pm
Hello fellow canadian. Thats a hell of a list for play bike i love it. I run a small performance shop here in red deer alberta. my .2

shell 91 is ethanol free even on east coast, its best pump i have found.

with the flat face valves boosting compression
pro ciruit cams
14.5:1
sea level (full air density)

yes you need race at least a splash fuel. a hugeeeee factor in what fuel you need is ignition. You didnt mention anything so i assume stock ignition. which puts it at a gamble on pump vs race with your specs. Can you get your hands on av gas from local small airport? if not vp t4 u4.4 great choices (t4 much cheaper but not oxygenated)

and if you decide you need race fuel, take full advantage of it with a vortex ignition or send your stock ecu to twisted development.
yvaillancourt371 2/21/2020 9:39am
2/21/2020 9:39am
Ok thank you, i forgot to mention that i plan to tune the bike on dyno And tune it with the kawasaki kx FI calibration program.
Hammer 663s
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Hammer 663s 2/21/2020 11:46am
2/21/2020 11:46am
For the few extra $$ per gallon, the safety margin is worth it. All it takes is one tank of crap pump gas and you detonate and undo all that work you did. At minimum, a 50/50 mix of Sunoco 100 or some VP and the best non-ethanol pump gas you can find.

I'd also spend a little more on a better oil. Maxima makes a number of good synthetics. I run Rotella in my kids bikes, but not in my Husky. 14,000 RPM baby.
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adam8781
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adam8781 2/21/2020 7:44pm
2/21/2020 7:44pm
yvaillancourt371 wrote:
has anyone experimented the octane booster? Is it a safe way?
i have and no its not, id back down your motorbuild plans if you dont want racefuel.
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mxb2
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mxb2 2/21/2020 7:57pm
2/21/2020 7:57pm
yvaillancourt371 wrote:
has anyone experimented the octane booster? Is it a safe way?
adam8781 wrote:
i have and no its not, id back down your motorbuild plans if you dont want racefuel.
Yep, all.the money in.the motor, use good fuel.
3
dmm698
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dmm698 2/27/2020 6:14am
2/27/2020 6:14am Edited Date/Time 2/27/2020 6:15am
adam8781 wrote:
Hello fellow canadian. Thats a hell of a list for play bike i love it. I run a small performance shop here in red deer alberta...
Hello fellow canadian. Thats a hell of a list for play bike i love it. I run a small performance shop here in red deer alberta. my .2

shell 91 is ethanol free even on east coast, its best pump i have found.

with the flat face valves boosting compression
pro ciruit cams
14.5:1
sea level (full air density)

yes you need race at least a splash fuel. a hugeeeee factor in what fuel you need is ignition. You didnt mention anything so i assume stock ignition. which puts it at a gamble on pump vs race with your specs. Can you get your hands on av gas from local small airport? if not vp t4 u4.4 great choices (t4 much cheaper but not oxygenated)

and if you decide you need race fuel, take full advantage of it with a vortex ignition or send your stock ecu to twisted development.
T4 is indeed oxygenated. im anywhere from 4-8% richer across the board with it via the FI mapping. Not sure why its touted as a pour in replacement, the stoich is almost as far from pump fuel as u4.4's stoich that comes with a 10% enrichment suggestion if I remember correctly (or like 2 main jets back in the day for carb stuff).
kb228
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kb228 2/27/2020 7:07am
2/27/2020 7:07am
A map & oxygenated race gas is going to do wonders to that engine. If youre going that far on the engine then might as well go for the map and race gas. Pump gas will hold back the potential.
fourfourone
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fourfourone 2/27/2020 7:18am
2/27/2020 7:18am
kb228 wrote:
A map & oxygenated race gas is going to do wonders to that engine. If youre going that far on the engine then might as well...
A map & oxygenated race gas is going to do wonders to that engine. If youre going that far on the engine then might as well go for the map and race gas. Pump gas will hold back the potential.
x2
yvaillancourt371 2/27/2020 6:20pm
2/27/2020 6:20pm
I was planning to dyno tune the bike with a guys who make a lot of Race bike for a friend that make the canadian championship and remap with the kawasaki kx fi calibration computer What type of fuel do you recommend using? Vp fuel.. sunoco .. what octane level? oxygenated or not? leaded or unleaded fuel?

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