TOPIC:

I've decided I want to advance both cams 2 degrees from stock. I won't change the lobe separation. Stock is 110 lobe center on IN and 110 on EX according to our pal zed1015. So my desired 2 degree advance on both cams means lobe centers should be 108 on IN and 112 on EX? Is this correct?

What is the goal....midrange - topend?

What engine config are you running?

These will help you out.
www.sportrider.com/suspension_settings/h...cam_timing_hands_on/
www.kzrider.com/filebase/doc_download/45...egreeing-for-zombies

Simple answer: Advance is clockwise when looked at from the right side of the bike. This is also the same direction they rotate with the engine running (or when you turn it over by hand).

To advance the camshafts means that you are rotating them so that they open earlier than stock. Therefore you are moving them in the direction they rotate an additional 2 degrees.

DoubleDub wrote: Simple answer: Advance is clockwise when looked at from the right side of the bike. This is also the same direction they rotate with the engine running (or when you turn it over by hand).

To advance the camshafts means that you are rotating them so that they open earlier than stock. Therefore you are moving them in the direction they rotate an additional 2 degrees.

The zombie articles seem to suggest that the lobe center numbers reverse from IN to EX. If that is correct, then adding 2 to each stock number would not be advancing them both. So if stock is 110 for IN and EX, then 112 is NOT advanced for both cams, only one of them. BUT I don't know if this is really correct or not.

So I'm still not sure whether the lobe center numbers go up or down when you advance.

I usually see intake numbers as ATDC and exhaust numbers as BTDC.

So if stock is 110 for both, then to advance them both 2 deg, you have intake at 108 and exhaust at 112, as you said.

I am no expert on this, but I remember from reading a long time ago, that advancing the cam timing helps low end performance, and retarding helps top end performance. Could be wrong.

www.webcamshafts.com/index_blank.html?pages/degreeing.html

by Doug Myers... Can't explain it any better than this....



Found this image of a cam degree wheel, may help put things in better perspective as well...

Cause I was bored....

Intake Cam:

Thanks everyone. glad to see loudhvx agrees with me - that's at least one vote that I have it figured out right

I like the degree wheel. I spose a person could print that out big and glue it to some cardboard = free degree wheel!

Old Man Rock wrote: Cause I was bored....

Intake Cam:

I was bored too dave and decided to ask; when your cruising your bike
down the road at 7,000rpm and are in third gear, that puts you at around 85 to 90mph.

twist the throttle all the way open and tell me,

does it pull
does it pull hard
how many rpm does it pull hard to.

then after wiping tears from your eyes

CHECK CAM TIMING LOBE CENTERS,
CHECK IGNITION TIMING,
CARB SIZE,
CAM LIFT,

ENGINE BUILDERS Let us know and we can tell whats going on with
the intake closing number and cylinder fill limit for the lobe centers you use.

We can tell what the usable rpm range is and non usable

Then we can tell what I MUST DO TO BEAT YOU

But maybe I've already done it

Just hit that throttle and bend some air, grit your teeth and smile into the wind,
you'll be grinning like a jackle from o to 60 thinking NADS could never catch me,

Then comes the dreadful part where power falls off, and life becomes shift after
shift, endless work and no more speed! Then the worst part, WHIZZ,