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going to premix


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erk4shooter

 
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going to premix

Tue Sep 18, 2007 10:18 am » Post: #1 » Download Post

Is it worth going to premix and what do i need to do if it is better??
Eric
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Matt@TYGA
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Tue Sep 18, 2007 11:42 am » Post: #2 » Download Post

If you're building a dedicated racer then yes, go to pre-mix. Easier to work on the bike (less clutter) and more accurate for continued high rpm use. You'll need to increase jet size to compensate for the oil in the fuel.

If you're an occasional trackday boy, then stick with the pump. Accurate enough for a 90% comitted track attack, and you won't have the headaches of carrying oil around with you and mixing at the pump during your everyday street rides.

If you'll not see the race track then stick with the pump.

If I were you? Pre-mix Wink Why? Because I hate clutter on the bike, and I can't stand having to remove and refit the 2T oil tanks on any stroker I work on.

Then again, if I were you then you'd be me, and I'd be asking you the questions Smile
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erk4shooter

 
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Wed Sep 19, 2007 9:55 am » Post: #3 » Download Post

Thanks Matt. I was just looking at how much hardware I can lose by going premix. I'm ok at math so oil mix should be ok (will know in a hurry if not!!) This is my first NSR so not sure what to fine tune.
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Andy
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Wed Sep 19, 2007 2:31 pm » Post: #4 » Download Post

It's much easier to work on with the oil injection removed, but unless you are pulling barrels off every 100 miles, I don't see the point.

The worst thing on a predominantly "street" bike is when you run pre-mix and hit reserve when you are flat out, run down a long hill on a closed throttle, or even under longer periods of closed throttle under braking, you are shutting off lubrication to the crank.

As Matt says, if you are accurate at measuring the fuel:oil ratio, then the mixture is more under your control which can be a great benefit when fine tuning a racer. Correct fuel:oil ratio can significantly effect hp and peak rpm. We had an RGV at one dyno day that picked up 1hp just by properly adjusting his oil pump!

The NSR oil system is pretty tidy though, and very convenient with the aux reservoir tank easily accessible. I'll be keeping mine in place on the 21 (I'm chasing 70hp with stock pistons and oil injection), but pre-mixing the 16 and 18 F3's.
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erk4shooter

 
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Thu Sep 20, 2007 9:27 am » Post: #5 » Download Post

Thanks Andy, appreciate the advice, I think I will stay with the pump for the time being.
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fontyyy

 
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Thu Sep 20, 2007 10:03 am » Post: #6 » Download Post

Also, premix uses about 3 times the amount of oil, the pump though rather basic compared to the TZR v-twin returns a lot better than 30-1.
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maxim
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Thu Sep 20, 2007 10:27 am » Post: #7 » Download Post

Yeah but it's so nice playing with volatile liquids!
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fontyyy

 
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Thu Sep 20, 2007 8:04 pm » Post: #8 » Download Post

And obviously your bike will smoke a heck of a lot more on tick over and when you warm it up which you may or may not view as pretty cool.
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StephenRC45
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Thu Sep 20, 2007 8:07 pm » Post: #9 » Download Post

Talking to Geoff at Rock Oil this weekend he was saying alot of the racers using Rock are now running 40:1 which is alittle more like what we used to run the MX bikes on.

I personaly still run 33:1 though down from HRC recomended 30:1.

Still on 40:1 it wouldnt smoke that much... ever lol
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alannsr250

 
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Thu Sep 20, 2007 10:03 pm » Post: #10 » Download Post

my mz smokes on 50:1 even when hot :/ and smoke is cool and smells nice Wink

i am a big fan of the pump just needs to be checked every now and then and keep an eye on the exhuast to make sure she smokes still.
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Sat Oct 06, 2007 7:10 pm » Post: #11 » Download Post

Is it possible to run premix for everyday use due to oil pump failure and go to the gas station and put petrol in the tank and then put the correct amount of oil in the tank and then shake the bike to atomize the mixture?
I have seen people doing this but is it safe?
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StephenRC45
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Sat Oct 06, 2007 7:14 pm » Post: #12 » Download Post

It not perfect to mix it at the station but its doable. Turn the tap off though before you add the oil.
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NSR-LOVER

 
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Sat Oct 06, 2007 7:20 pm » Post: #13 » Download Post

I am thinking of doing it when i fix the bike cause i had a ''small'' seizure and i havent checked the damage yet.
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cgallant
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Sat Oct 06, 2007 9:51 pm » Post: #14 » Download Post

NSR-LOVER wrote:Is it possible to run premix for everyday use due to oil pump failure and go to the gas station and put petrol in the tank and then put the correct amount of oil in the tank and then shake the bike to atomize the mixture?
I have seen people doing this but is it safe?


Your actually better off putting the oil in first, then putting the petro in. let the rush of gas help with the mixing of the petro, then follow it up with the some shaking of the bike.

of course to do this you need to know pretty much how much fuel you need prior to putting it in so you get the proper oil mixture.

The other option is to carry a couple gallon fuel jug with you and a mix cup to measure up your oil Smile
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erk4shooter

 
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Sun Oct 21, 2007 8:50 am » Post: #15 » Download Post

how do i plug pump etc to go to premix. oil always goes in b4 petrol, its the only way to get a good mix hapn.
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