question about ign advance , am i right ???

[hyofighter]

so the dirt dragger is getting a guts full of avgas ths weekend to try and to get the most out of it i want to advance the ignition a few degrees , now i have seem the factory pro crank mounted rotor/reluctor and i see the the trigger is further clock wise than the top dead mark than a factory unit , understandably this is advanced right

http://i.ebayimg.com/t/Factory-Pro-Tuning-Ignition-Advancer-Advances-4-Suzuki-GSXR600-GSXR1100-GSXR750-/00/s/NDk5WDYwMA==/z/I9wAAOxy4~BSSKiR/$(KGrHqF,!rcFI3gQU+J)BSSKiRhG)g~~60_3.JPG
so when i go and search the googles i find 2x threads where people have "advanced" there ignition by sloting the holes in the backing plate and rotated the pickup clock wise , both claiming to have more power

http://i34.photobucket.com/albums/d118/chriskat1100/bikepics-304533-full.jpg

http://www.gixxer.com/forums/showthread.php?t=184843&page=2 (half way down the page and before and after photos show clockwise rotation)

now i am i right in saying that they both have retarded there timing ?? if the engine rotates clockwise then you would move the backing plate anticlock wise for advance for sure

[latheboy]

I retarded my ign 4° by rotating the plate Clockwise.

You will need to rotate your plate Counter Clockwise to advance it.

Listen for the kabooms :)

That guys marking out is pretty rough...... Don't do it like that!
Also, half of the pictures in that thread are mirrored.
The first picture showing his marking out is flipped, whereas the second is correct, look at the texter writing.

[hyofighter]

did see that but the before and after looks to be retarded too , either way i think i had over thought about it and doubted myself. i was only going to go a couple of deg advanced thats all

[Hagarr]

did see that but the before and after looks to be retarded too , either way i think i had over thought about it and doubted myself. i was only going to go a couple of deg advanced thats all

Two different situations!

The rotor signal point is moved clockwise to advance because its the bit that spins, so when you move the point clockwise you advance the point at when the ign triggers and when the signal is sent, the plate needs to be moved opposite to the rotor to advance because it is the bit that is stationery and by moving the plate anti clockwise has the same effect as advancing the ignition or making the rotor trigger at an earlier point.

[hyofighter]

Absolutely fully understand that but it was the net info that got me all confused. I gave it 3 deg then went to test her out and has a needle and seat seat oring thats split and flooding her so off with the carbs again and replace them all

[Hagarr]

Ah OK

[ozzy1100]

I'll see if I can dig up pics of the adjustable one I made yrs ago

[jmw76]

AvGas does burn a little slower. You may need a little more advance and more importantly you will need to go up a couple of jet sizes as it burns leaner.
To advance the ignition you rotate the back plate counter clockwise as you have already concluded.
Mark the plate first so you have a 0 degree reference point to work from.
My personal experience running AvGas was not all that conclusive. I did it because I needed a bit more detonation protection.
I really didn't notice any power gain.
I have since switched to JFP105 which burns a lot faster and has a higher octane rating than standard fuel. Also slightly cheaper than AvGas.
You will need to retard the timing for this and jet size will be about the same as for pump fuel.
Ideally you want a fast burning high octane fuel.
Don't spill any of the JFP on your paintwork. It rips the gloss off really quickly.

Cheers

Peter.

[hyofighter]

well thats pretty much what I had done , I marked the plate in its factory state removed it modded the holes marked it to 5 deg more reinstalled moved it to 4 deg , I also had raised the needles a clip and opened the gap in the plug a bit , seat of the pants on sat was hard to tell as the track was very loose and dry but it did seem to pull well and im sure a bit of advance will do that too , id be interested to here more about this JPF105 as I got the avgas at 2 bucks a litre and I did price some 109 octane from a performance shop but at 235 bucks for 20ltrs my dirt dragger isn't that serious

[hyofighter]

also im guessing now days the avgas isn't lead based as I seem to remember avgas turning pipes grey ? mine after the weekend not so

[Redmohawk]

Lead will only turn the pipe white if its running fairly close to stoch , (grey is about right for what your doing) black is rich if its 100/130 (green coloured) its got lead in it if its 100LL (blue coloured) its got half as much lead (still more than old car petrol used to have).

Doing a plug chop is an easy way (better) to see what going on inside the donk at power.

[jmw76]

$2 per litre is pretty good for avgas. The avgas you can buy today tends to be the low lead stuff. It has a different colour than the full leaded stuff (blue vs green). Supposed to be as good as the old stuff, but I have heard varying reports.

I buy JFP105 in 20L drums for about $70. For comparison, from the same place I would pay $75 - $80 for Avgas.

Here is the link for JFP105. You should be able to find a supplier near you.

http://www.cheetahracefuels.com.au/JFP105.html

I run a normally aspirated set up with a CR of over 13:1 and I never have any issues. Well at least none that I can relate back to the fuel.

The JFP stuff is also better for me as it gives better fuel economy compared to the Avgas on the track. With only a small tank, it reduces the number of refills during the day and allows me to get more laps in on a tank.

Cheers

Peter.

[Hagarr]

My personal experience running AvGas was not all that conclusive. I did it because I needed a bit more detonation protection.
I really didn't notice any power gain.

Same here, going from Avgas to 98 pump fuel on seat of pants on Avgas, engine felt a Tad smoother but no discernible notice of change in power!

Smells great though!

[jmw76]

If fuel consumption isn't an issue then E85 is worth looking at. The racing stuff is actually quite cost effective.
You will need really big jets though (on my RS40s, I would need jets around 200 or so. Currently using 145). But it burns quickly. V8 supercars run it as do a number of people I know with high performance race cars (turbos). It has a very distinctive smell also.
It is hard on some of the old rubber components in your fuel system so you will have to drain it after every meeting or upgrade all of your lines. 'O' rings etc.
I find I have to drain the JFP105 anyway as it goes off very quickly if left sitting in the bowls and then it's a bastard to get the thing started.

Red is on the ball for getting an idea of how things are running. I always like to visually inspect the plugs to see what is really going on. There is a real technique required for doing this properly. Go speak to an older guy and learn how this really should be done. There are a number of articles on the web that are quite good also.

Peter.