Evo timing question

[Bullwinkle]

A timing question came up. It seems that most mechanics around here set the static timing at 0 with the timing mark in the middle of the hole, then let the module do the rest of the job with some tinkering with the switches. That's an easy enough way to do this, but it doesn't seem to be the best, at least on my scoot.

I can't seem to find a curve on the ignition box that this engine likes (DTT external box) and am wondering if I should perhaps set a couple more degrees initial.

On most of my cars, what seemed to work pretty well was higher initial timing, then a steeper curve with slightly less advance in it. I don't know if this would work, and can't afford to find out the hard way if it doesn't. <grin>

It's an Evo engine with ported and cut SE heads with about 9.5 compression and a 240 degree, .560 lift cam.

Can someone bring me up to speed on this?


Bullwinkle

[hardluk1]

Tell what bike and year you have and what ignition If you have your info sheet for the timeing it will tell you how to go about finding a good setting. I am running stock heads and pistons with ev23 cam and a cumpu-fire ignition and have mine set at # 3 position and thats 35* timeing by 2250. at 50% voes. So read your fact sheet a follow the directions.

[Bullwinkle]

The bike is a 1999 FXR with the 80" Evo engine, shaved and ported SE heads, about 9.5 compression, and a Daytona Twin Tech box. The timing is set as the book says, with the timing mark in the middle of the sight hole.

The carb is spot on and the pipes are V&H Straight Shots.

I'm not impressed with the performance and I've gone up and down the range with the curve switches. I'm beginning to think I might need a little initial timing, maybe a couple to as much as five degrees.

The reason I'm not impressed is that I can be running down the highway at about 2800 and when I pull the throttle back, not WOT but maybe half way, I get quite a bit more noise but very little acceleration. It should be better.

Anything to this, or should I buy a cable, download some software, and try playing with the module? That's not an attractive choice to me, since I really odn't know much about using software to do this.


Bullwinkle

[Bullwinkle]

An afterthought:

Is all tinkering with the timing done through the module switches, or can it safely be tuned further by moving the pickup module?

More accurately, what is the chance that I might hole a piston? I don't intend to go far, but how much might be too much?

Bullwinkle

[Otto]

try curve 6 and advance triggerplate 1 hash mark and try it again

[Bullwinkle]

Thanks, that's what I needed to hear. I thought that tinkering with the initial timing would help, but wanted some reinforcement from here. If it helps I will have a good solid baseline to begin fine tuning.

Bullwinkle

[econnor]

The key to setting the timing plate is final advance. On an Evo, all advance is in by 2500 rpm and Evo timing is 35 dgrees full advance. A hopped up engine will need a few degrees less advance.

This is how I set mine: I use a dial back timing light and rig up a pointer to point to the perimiter of the front compensator sprocket. With the top dead center mark in the center of the timing hole, place a mark on the compensator that corresponds to the pointer. Put the timing plug back in the hole. You can now time this engine without getting oil all over you and your timing light.

Start the bike and raise the idle to about 2500 rpms. Now point the timing light at the pointer and adjust until the mark is inline with the pointer. Read the advance on the timing light and adjust the plate until it is where you need it to be.

This might not be the school solution, but it is very precise and will not get oil all over you.

Ed