It's a long way to 920 type(rary)

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Mike, can you explain the relation ship behind the idea of a tad too much advance and non protruding plugs?
 
Nigel, perhaps my explanation looked like it ran together.
My guy thought going by the pics there was too much advance in the first instance and secondly , while trying to get his jetting right , perhaps Yves could try a different type of plug , ie , non protruding type.
My guy is not an advocate of the protruding plugs for the higher performance motors as it puts the centre of the plug especially iridiums closer to the piston .
He was keen to see pics of the top of Yves's pistons before he made any more changes.
We zoomed in on the pics and there is some fine specs on the earth tang which can indicate too much advance.
Make sense?
Regards Mike
 
If you are getting aluminium particles on the plug, you are way too lean. If you fit the equivalent to a NGK 9 plug and your mixture is correct, when you use a light and look right down inside the plug, there should be a 2mm wide black ring on the porcelain down inside, where it meets the metal. That determines whether the combustion temperatures are correct. Ignition advance and carburation work together so that the engine doesn't run with stress but gives max power. I always use main jets which are slightly too rich. It is unusual to cause damage when the throttle is not open beyond where the needle and needle jets have effect. If they are too lean, you will usually know it, but lean enough is good.. If you use NGK 8 equivalent plugs, the black ring will disappear quicker, so start richer. If you jet lean on the needles, colder weather might make the jetting even leaner, so you need to allow for that, especially if you ride long distances on part throttle.
 
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Brooking 850 said:
Nigel, perhaps my explanation looked like it ran together.
My guy thought going by the pics there was too much advance in the first instance and secondly , while trying to get his jetting right , perhaps Yves could try a different type of plug , ie , non protruding type.
My guy is not an advocate of the protruding plugs for the higher performance motors as it puts the centre of the plug especially iridiums closer to the piston .
He was keen to see pics of the top of Yves's pistons before he made any more changes.
We zoomed in on the pics and there is some fine specs on the earth tang which can indicate too much advance.
Make sense?
Regards Mike
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That’s interesting to know Mike, thanks.
 
There are two variables - jetting and ignition advance. I always fix the advance curve, then jet to it. I don't change the advance curve to suit the jetting. The needles in Amal and Mikuni carbs are tapered to compensate for the change in vacuum as the throttle opens.
 
Here what I did to day:
First I put the clips on grove 6 on the EMR needle, the flat spot was worster as on grove 5, I decide to go back to the leaner EMT needle who is leaner as the EMR, I put the clips on grove 4, I did a test ride and the flat spot was gone and the bike was flying.
I try to find the reason, becouse on the first pics you see the sparks way to lean, but I change the main jets from 175 to 185 and on a Keihin the main jet as influence from 1/8 throttel opening so the EMR was to ritch maybe??
After I strobe the ignition from 29 to 27 degress and make another test ride, bottom power was mutch better and still very fast at high RPM
Tomorow I will do a test ride from 100 kms and will look at the spark plugs.
As you know I order the velocity starks with the air filters adapter from Power-Barn, I pay a lot of money for the shippment, was garantee to be here at 8/1 and still nothing
USPS was in charge and when I put the tracking # they just says the package is on transit to the next facility but they don't says witch facility...
Keep you posted
Yves
 
I don't know if you cd call it "lucky", but usually the freight cost is free IF the guaranteed deadline is not met. I hope you get them soon, and don't have to pay for the shipping!
 
Mr. Rick said:
I don't know if you cd call it "lucky", but usually the freight cost is free IF the guaranteed deadline is not met. I hope you get them soon, and don't have to pay for the shipping!
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I pay already the schipment by Pay pal to Power-barn, and it is not the first time Ihave problems with USPS and also with UPS, Fedex is the only that works good
Yves
 
Then I expect that Power Barn will get their money back. And really should give it back to you, with a PayPal refund.
 
Hy there,
Yesterday I receive the K&N filters adaptors, put it on the carbs and did a test ride: difficult to say if better, I think yes...
Jan Egil send me a mail with details about reading the spark plugs, very good and easy to understand, so I follow the instructions and decide to go leaner with the main jet:
from 185 to 180 and this make a real difference, after a new test ride the plugs looks OK and the power also. I don't think I can't do better w/o dyno, I will try to go to the dyno next week
Keep you posted
Yves
 
Hi there,
Don't think I am dead, I am still working on the Carbs and Ignition and every WE I make a few 100 kms
BTW, no problems anymore with the HG, no leak with the 0.5mm gasket from Jim Schmidt and Pliobond.
Power- Barn is the web site to be, I find not only the starks with K&N adapters but also the Boyesen Engineering Quickshot 3 with adjustable pump cover, the best stuff you can buy for Keihin FCR carbs, I try to explain with my poor english:
On the FCR you have a accelerator pump, this is needed becouse with big carbs, you can not create a vacum big enough to have the fuel coming the normal way, thats why they use the accelarator pump, just to supply more fuel when you go WOT.
The only bad thing is that on FCR, there is no way to adjust the duration of the fuel injection, on FCR MX well but not on standard FCR, and here is why the Quickshot 3 is wonderfull: on the pump cover there is a adjusting screw and with this screw you can adjust the duration from the fuel injection, this screw send the needed amount of fuel to the injectors, and when there is to match fuel injected, you can adjust the by pass return to the bowl.
And it's work: just need to have a screwdriver in your pocket, I try different setings and 3/4 off turn out give the best result fot my engine.
I order also from Power Barn the Dual spray fuel injectors, the problem is that you wust strip the carb and take the mid body off, easy to do on FCR MX but not on normal FCR: the mid body is glued with epoxy and there is a O ring also, so I send a email to Matt from CNW and he contact is distributor and here is the antswoord, of course you can break th epoxy seal, but doing that you will break the O ring AND KEYHIN DONT SUPPLY THIS O RING!
So I decide not to use the dual spray at the moment, I must go to the dyno next week and I have the 1/8 mile dragster race on sptember 2, this will be the judge, I hope to make a better time as last year.
Keep you posted
Yves
 
I forgot to thanks Matt from CNW I ask him a question and 5 minutes later I receive the detailed antsword, Matt you the are the man!!
Yves
 
Good luck with the drag race Yves.

Only saw you briefly in the collecting area on Sunday. I came looking for you after, but maybe too late. Hope you enjoyed the day.

Of course you saw I still have the iron barrel, since the race season is over for me I shall start work soon to strip it down and rebuild for next year.

Steve
 
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SteveA said:
Good luck with the drag race Yves.

Only saw you briefly in the collecting area on Sunday. I came looking for you after, but maybe too late. Hope you enjoyed the day.

Of course you saw I still have the iron barrel, since the race season is over for me I shall start work soon to strip it down and rebuild for next year.

Steve
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Hi Steve,
It was good to see you racing at Gedine, my bad legs don't allowd me to cross the padocks.
The drag race is next sunday at Eeklo here in Belgium, of course I will compare the time on the 1/8 mile that I did the years before with the time I will do sunday,
That will be the judge for all the work I did the last year, I hope to go under 8 seconds...
Keep you posted
Yves
 
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