Ignition Timing : V-Twin Forum: Harley Davidson Forums

Harleyd · 11-06-2009, 02:31 AM

On the cam sensor plate on a 99 evo there are small graduations to adjust timing advance or retard. My question is, in degrees what are there values, the number of degrees between the marks?

I'm putting in KB cast 9.5 pistons and will end up with 9.7-9.8 compression. KB recommends backing the total advance off by 2-4 degrees. I have also heard/read elsewhere when raising compression that you should retard the timing a tad.

Kent · 11-06-2009, 04:36 PM

If I recall correctly each graduation is 1 1/2 degrees. Even on my stock 94, I like the timing retarded 3 degrees.

Kent

Harleyd · 11-08-2009, 12:49 AM

Thanks Kent.

A lot of speculation and hear say that I am hearing and reading points to the 2 degree neighborhood, I am beginning to think it is 2 degrees. I would however like to hear some real fact as to what the graduations really represent.

Check out this procedure on timing the evo from the right side. It sounds real good. I wonder if there are any hidden adversities.

http://www.wildwestcycle.com/f_timingtrick.html

Kent · 11-08-2009, 10:55 AM

Harleyd, my info comes from a book - 101 Harley-Davidson Evolution Performance Projects By Kip Woodring, Kenna Love - in which the authors state on page 44, "Each of the tiny hash marks stamped in the base plate represents 1.5 degrees," They show a nice picture of the sensor plate assembly with their explanation.

Kent

Harleyd · 11-09-2009, 03:57 PM

Thanks kent! I appreciate the info.

spgtti · 11-09-2009, 10:56 PM

http://www.v-twinforum.com/forums/tw...ate-marks.html This is the answer I got years ago from some old codger that might know.

spgtti · 11-09-2009, 11:07 PM

Quote:

Originally Posted by Kent

Harleyd, my info comes from a book - 101 Harley-Davidson Evolution Performance Projects By Kip Woodring, Kenna Love - in which the authors state on page 44, "Each of the tiny hash marks stamped in the base plate represents 1.5 degrees," They show a nice picture of the sensor plate assembly with their explanation.

Kent

Kent, Hope you didn't buy into the "Fuel-Stat" fuel de-ionizer too. That gadget's on page 72

route66paul · 11-10-2009, 01:35 AM

As with twin cams, evos need to have accurate combustion chamber measurements to get the correct static compression. You can never assume anything, cc the heads, figure out what your deck height is and correct it if need be and use to correct head gasket with the correct torque sequences. if you get the static compression correct, the rest should fall right into place, unless your cam is off.

Dr.Hess · 11-10-2009, 10:20 AM

Quote:

Originally Posted by spgtti

Kent, Hope you didn't buy into the "Fuel-Stat" fuel de-ionizer too. That gadget's on page 72

What, are you saying this isn't true? Why, I put the magnet fuel de-ionizer on my bike and immediately got 65 more HP, proven on a dnyno.

Here's the dyno charts to prove it:

Before:
|
|
|
|
|----------------------------------

After (with Fuel de-ionizer and motor running_
| - - - - - - - - - - -
| -
|-
|
|----------------------------------

Anyway, if you're playing with the timing like that, I wouldn't go by the hash marks at all, but get one of those fancy lights that you can adjust.

Harleyd · 11-14-2009, 01:07 AM

Thanks for the`follow up posts. I will be using a dial back timing light to dial in the timing at this point. I just thought if you had the static timing correct and knew what the graduations were, you can just rotate the cam sensor disc 1 or 2 marks and be where you need to be.

Based on the last few post's I assume the book Kent is refering to is a snake oil publication.??? At the same time I have heard and read approximately 2 degrees is the value. I will say that I never checked out this book, "101 HD projects".

Route66:
No flame intended, but how does your post relate to setting the timing to a specific value using the marks on the cam position sensor plate? Please advise me if I am over looking something.
Thanks!

Harleyd · 11-14-2009, 01:23 AM

spgtti:

Thanks for the link to that post, don't know how I missed that one. Yeah, I did a search. As I said in my last post I will be using a dial back light. I will also varify those numbers and post if anyone is interested.
Thanks again spgtti!

BTW, do you have to set the dial back light to 2X the disired timing value to get the TDC mark in view due to dualfire function?

bigbadal · 11-14-2009, 09:29 AM

Quote:

Originally Posted by Harleyd

spgtti:

Thanks for the link to that post, don't know how I missed that one. Yeah, I did a search. As I said in my last post I will be using a dial back light. I will also varify those numbers and post if anyone is interested.
Thanks again spgtti!

BTW, do you have to set the dial back light to 2X the disired timing value to get the TDC mark in view due to dualfire function?

If you are going to use the dial-back timing light, try this: Take the timing plug out of the timing hole, put the long, threaded plastic plug in the hole till it touches the flywheel. Back the plug out an eeny bit. It helps to have clean oil in the engine, you can see the mark easier. Get a nice chunck of wood that will fit your bike and put it on the right side under the frame or floorboard brackets and lean your bike over to the right side. Not too far, just kinda make it lean like it had a jiffy stand on the right side. Then hook the timing light up and start the bike, hold it at 2500rpm. Start with the dial at 0, slowly turn the dial back till you see the mark in the plastic plug and read the degrees on the back of the timing light. Now you know where your timing is set at. Adjust your ignition to put it where you want it. Sometimes it is difficult to see the mark when the oil is black. A great reason to use the dial-back is that it is easier to see the vertical hash mark rather than the little dot in the window.