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Re: Gifts to you know who in 2015

Posted: Tue Apr 14, 2015 7:58 am
by Greg Watters
Wondered what happened Gary, bad luck indeed , can the tensioner arm be secured or limited in its travel ? or is it more an adjustment in fuel and timing that it does not kick back ?

our offering is not metal , new bodywork did not work for us, giving a speed related wiggle , seems the centre of pressure is too high for our centre of gravity
older style on the 750 that we tried on the busa last day worked much better , but our rushed fit must have been offcentre or had a side wind on track that i could not feel off track as it had a speed related lean
Image

So back to the drawing board

Re: Gifts to you know who in 2015

Posted: Tue Apr 14, 2015 8:20 am
by Stayt`ie
on the weekend we pulled the motor and our humble contribution this year is one piston,, oiling problem to #2 gudgeon, flogged out a few thou, no worries :roll: ,,
given that we had 30% in the tank and are newbies to this Nitromethane stuff, very happy with the readings of the complete cumbustion chamber, no signs of detonation, :D ,,
going to have the "new" battery checked out, as i feel it was going away causing a voltage drop which resulted in the fuel pressure droping, :evil:

Re: Gifts to you know who in 2015

Posted: Tue Apr 14, 2015 9:53 pm
by BONES
Dave
Shell M is good -- castor base
20:1 should be fine. I run all my engines at 20:1 castrol 747 and petrol.
Maybe a richer needle?
Alcohol wont loose power if it's a little rich but will detonate if lean.
Lots of guys use alcohol in yamaha air cooled road racers so I would think part throttle should be not a problem if jetted correctly.
Is it maybe worth using some oxygenated petrol to give close to the same power which should be ' more normal' to tune.

How did the cylinder fair? Will a little acid clean it up?

Well I guess 11 months to get it right
cheers Bones

Re: Gifts to you know who in 2015

Posted: Wed Apr 15, 2015 1:22 am
by RGV
Hey Bones, the cylinder needs a replate, a few scores.

Its been suggested to me by a knowledgeable tuner in England that the needle moving around in the needle jet might cause problems to fuelling so I have now locked mine so they dont wobble.

He also suggested filling in the bottom of the slides to give a better signal in the mid range. You can buy bits of plastic to do the job but im not paying $50 each for them so Ill have a go at making some.

What sort of power increase do you get from the oxygenated petrol? Ive seen some pretty wild claims.

Im going to give methanol another try next year and hopefully get it right this time.

Dave