VOES adjustment

davidcar · #1 9th May 2007

Not sure what the normal process is, so I thought I would post this and see what happens. As adjusting the VOES is often required when a conversion has been carried out, my thoughts are that having a sticky on the subject will be beneficial for easy reference.

VOES ADJUSTMENT

This method allows you to fine tune the VOES to work best for each individual combination of engine set-up, weight of the bike and weight of the rider

When you crack the throttle you want the curve to switch as soon as possible but without causing detonation, by physically seeing when the curves switches you can adjust the VOES to an optimum setting without getting ping.

I used this process and it worked very well and all you require is basic tools some electrical auto wire and a LED light. I get no detonation and my bike lifts the front wheel off the road so much easier now.

Firstly unbolt the VOES from the mount on the bike but leave the wires and vacuum line connected.

Warm the bike up to operating temperature and then turn the engine off.

Remove the silicone seal/fill from the VOES to expose the large screw (be gentle).
The screw only needs adjusting 1/4 turn each time.

Expose the ignition module so that you can see the VOES light, then start the bike and adjust the idle speed to your normal idle speed approximately 850RPM-950RPM.

ATTENTION: If your ignition module does not have a VOES light in it then install the LED light as described below and use it for the following adjustment.

Now observe the VOES light on the ignition module and see if it is on almost continuously or if it is turning on and off rapidly.

If the VOES light is on for longer periods than what it is off then this is your starting point.

If the VOES light is turning on and off rapidly, turn the VOES screw clockwise a ¼ of a turn at a time (wet your thumb and seal the VOES where the silicone was) until it stays on almost continuously, then turn it clockwise a further ¼ turn, this is your starting point and will be very close to the correct adjustment (usually within 1/8 to 1/4 of a turn either anticlockwise or clockwise).

Seal the VOES by placing a small piece of paper over the screw head and then fill the hole with clay

Now using a 12 volt LED light a red one is good (I used one that was approximately 2&1/2 by 1&1/4 inch) and a 6 inch & 18inch length of electrical wire.
Splice into the VOES ground wire (on the bike) using the 6 inch wire and connect it to one side of the LED light.
Then using the 18 inch wire connect one end to the LED light and connect the other end to the positive terminal on the battery.

This is where the LED light is useful because you can see what is happening while your ridding/testing.

If you crack the throttle and get ignition pinging and the light does not go off, you need to adjust the VOES screw so that it will switch to retard sooner

Example: The light should stay on while you are slowly overtaking a car (to checkout that spunky looking chick driving the car your passing) but the light should turn off when your passing a line of cars and there is oncoming traffic and you want to avoid a head-on collision with or if you are racing another bike.

If it is switching too late then turn the screw ¼ of a turn anticlockwise. (test it again)
If it is switching too soon then turn the screw ¼ of a turn clockwise. (test it again)

NOTE: At idle or at cruise or at easy acceleration the ignition will be advanced, and the VOES light will be on. The light will be on most of the time you're running.

When you get the VOES to the right setting, reseal it with silicone.

Horse · #2 9th May 2007

This is an extremely important step when doing a conversion on a bike with VOES. Heck, I adjusted my sisters 2001 1200c stage 1 and it made a noticeable difference in her throttle response.

raysheen · #3 9th May 2007

seems to be interest and there aren't many stuck threads in this section so I've stuck it for you. Thanks for posting.
Note: I edited the title of the thread so that it would make sense as a sticky title (removed the voting request)

groovemeisterus · #4 27th May 2007

What would be the proper procedure to mod the VOES with
a stock 2000 883 XL to 1250cc conversion with vance and hines straight shots
exhaust and the new SE 07 aircleaner (looks similar to the forcewinder
type of air cleaner) with an SE HSR 42mm Mikuni Carb?

Where should I start to look into this mod to fit my configuration? From
knowing my riding style etc. A foundataion to start from and learn from
on how it works and makes a difference?

Thanks for any advice.

davidcar · #5 27th May 2007

If you read the above a few more times it should make sense, all the info you require is there.

Quote:

Originally Posted by groovemeisterus

What would be the proper procedure to mod the VOES with
a stock 2000 883 XL to 1250cc conversion with vance and hines straight shots
exhaust and the new SE 07 aircleaner (looks similar to the forcewinder
type of air cleaner) with an SE HSR 42mm Mikuni Carb?

Where should I start to look into this mod to fit my configuration? From
knowing my riding style etc. A foundataion to start from and learn from
on how it works and makes a difference?

Thanks for any advice.

groovemeisterus · #6 28th May 2007

Quote:

Originally Posted by davidcar

As adjusting the VOES is often required when a conversion has been carried out.

Why?

[/QUOTE]

Quote:

Originally Posted by davidcar

This method allows you to fine tune the VOES to work best for each individual combination of engine set-up, weight of the bike and weight of the rider.

So how does my combined weight of me and my bike come into play
during adjustment?

Quote:

Originally Posted by davidcar

When you crack the throttle you want the curve to switch as soon as possible but without causing detonation, by physically seeing when the curves switches you can adjust the VOES to an optimum setting without getting ping.

Does the VOES (Vacuum operated electronic Switch) need to switch at
an optimum RPM?

Quote:

Originally Posted by davidcar

Remove the silicone seal/fill from the VOES to expose the large screw (be gentle).The screw only needs adjusting 1/4 turn each time.

I suppose i'll have to cut into the metal caseing to get to the screw?

You could also re-seal with silicone since the clay might dry out?

I don't mean to come off rude. Sorry if you get that impression.
Sorry so many questions but I am a very curious person when it comes to
making adjustments on my bike and like to learn the fundamentals before
I mess things up. I am a software engineer and sometimes ask toooo many
detailed questions. This is my nature.

Thanks for any reply

I just finished my 883-1250 conversion so I thought I would check out
this thread.

Horse · #7 28th May 2007

Let me see if I can't answer a few questions. Most conversions up the compression by a good bit over stock. Now, an 883 vs a 1200 engine has a completely different advance curve on the ignition, along with different max advance numbers. Take the added compression, and the difference in advance curves from what the voes was set up for, and what you have is a formula for pinging. The VOES will incorrectly determine when the engine is under light load and advance the timing too soon, based on the vacuum generated by the new displacement. On the VOES unit, the adjustment screw is hidden behind a silicone plug, it's not obvious at first glance, but if you touch it, you'll know it's silicone. Just cut that plug out with a knife or other suitable tool to gain access to the VOES adjustment screw. I used a vacuum guage and listened for the click to set mine, others like Davidcar use the light etc. Either way is fine as long as you take the time to make sure the unit doesn't prematurely advance your timing. Mine was set at 4lbs from the factory, it ended up at 6.5, I believe each is unique to a certain extent. The clay plug is just a way to seal the vacuum around the adjustment screw as you test the different adjustments. Much easier than re-siliconing between each adjustment. Hope my explanation cleared some things up for you.

groovemeisterus · #8 28th May 2007

Thanks for the info. It did help clear up a lot of things on the why.

About the location of the screw etc... (I have a 2000 883 XL model year and maybe different on diff years), is the screw located on the side where the conectors plug in, or on the other side cover inside the metal where the o-ring clamps the VOES to its mounting bracket? I'll need a hack saw.
I didn't say in my service manual.

Not exact, but hopefully close enough ascii pict.

Metal side the + represents where I might think the adhustment screw
would be? or on the wire (harnes plug) in side? and the o represents where the vacuum line from the carb plugs in.

wire Metal cover side
plug
side
---|-----\
---|o +|
---|-----/

Thanks.

groovemeisterus · #9 28th May 2007

I think this might be a little better of a pict compared to my ascii art pict.
I used my web cam.

davidcar · #10 28th May 2007

The screw is located at the end closest to the bracket numbered 3 in the picture, once you take it off the bracket and turn it around you should find it.

Quote:

Originally Posted by groovemeisterus

I think this might be a little better of a pict compared to my ascii art pict.
I used my web cam.