timing wheel?

[emilios]

Hi
Im just wondering where and how to put timing wheel to set ignition timing..

[MG]

Hello emilios!

You can put the timing disc on either end of the crankshaft and tighten it with a suitable nut.
With everything assembled (oil pump drive, primary cush drive) I have also fitted it to the outer nut of the primary cush drive with simple double-sided adhesive tape. I usually make a pointer out of a piece of wire and tighten it to the engine casings with one of the cover screws.

[emilios]

thanks MG...
I set ignition timing without head before a week or so....but i forgot to check both cylinder..
So i will check tomorrow but i dont want to take head off...so i will do it with the timing wheel..
I looked around some topics and found out that 3/8 is 35.5 degrees...

[MG]

With the iron head models I don't use more than 33 deg, otherwise they tend to ping under load.

[emilios]

Yes but i put hc pistons and thats what the supplier set..3/8
???

[MG]

Maybe the HC pistons were designed for the alloy head models?
36 deg BTDC would be the timing figure for the Rocket.

[emilios]

Do you thing that HC pistons will cause any problem to my iron head engine? or if i stay down to 33 deg will be ok?

[MG]

I'm running the iron head GF on 9:1 without any problems (@33 deg). Just found it tends to ping when advanced further than 33 deg.

[emilios]

Ok so im going to 33 deg tomorrow morning..

[emilios]

Today i checked if both cylinders fire the same time...and i found one at almost 34 deg and the other almost  26 deg...
After 2,3 attempts i have both cylinders firing 32 deg...
I didnt run bike far...only half mile or so but i notice much less vibration and much smoother engine...
im planning to do a 50mile trip tomorrow to see how it goes...

[MG]

Sounds good, congratulations!
32 deg is definitely OK.

Enjoy your trip tomorrow and let us know how it went!

Btw: What was the problem with the misfiring we discussed in the other thread? Faulty pickup?

[emilios]

I put new pickup and new plug caps...but it should be cap cause when i checked them with an multimeter they showed huge resistor....

[orabanda]

Running my 51 GF on a dyno showed that 30 BTDC was the best setting

[Brian]

Do any of you mathematical geniuses happen to know what 30 or 32 degrees is in distance before tdc. I run my A10's on 5/16" BTDC and that seems to be about right, go well and no pinging. Thats with iron heads, maybe the alloy ones would tolerate a touch more advance, maybe not.

[olev]

Brian, Take a deep breath, get a glass of your coonawarra red and a calculator.

T = L + R X (1 - CosA) -   the square root of ( L squared - ((R X SinA)squared))

where
T = distance BTC in mm
A = timing in degrees
L = conrod length in mm
R = engine stroke in mm divided by 2

You will notice I havent worked out how to do the square root or squared symbols
cheers