Ignition Timing adjustments for more performance

[eagles22793]

I have a 2000 yz125 that I am redoing thhe top end and putting a wiesco pro lite piston kit and high compression gasket kit. I off the ignition timing cover to check everything and see that the timing is set about a degree or two before the correct aliment. I know this is better for the heat but I want to get more power out of the bike to race. I want to advance the timing a little but am not sure on how much and it what conditions so I dont blow it up. Can anyone help me?

 

[helio lucas]

with the higher compression and advanced timing you may have to run race gas and richer jets.
some bikes respond well to advanced ignition timing but if i remember correctly on the 2001 model the bike has lost some peak power and over rev but gained some punch out of turns.

a little search on the archives may bring you a better answer than you ask :cool:

 

[eagles22793]

I am plannig on using race gas I think 106 octane but I dont know how much to adjust and in what weather conditions to advance or retard the timing?

 

[eagles22793]

YZ125 Help

I put a thread on here about a month ago about putting a wiesco pro lite piston and thinner base gasket. I saw that the ignition timing was set a little before stock so I advanced it to stock position. Most people told me that I will have to use race gas and richen the jets but did not work that way. I used the race gas and mixed it 32:1 and the bottom end is choppy. I went down on the pilot once and seemed to fix a little but I dont want to keep going down and there is something else wrong and burn the bike up. What should I do?

 

[eagles22793]

yz125 help

I put a thread on here about a month ago about putting a wiesco pro lite piston and thinner base gasket. I saw that the ignition timing was set a little before stock so I advanced it to stock position. Most people told me that I will have to use race gas and richen the jets but did not work that way. I used the race gas and mixed it 32:1 and the bottom end is choppy. I went down on the pilot once and seemed to fix a little but I dont want to keep going down and there is something else wrong and burn the bike up. What should I do?

 

[whenfoxforks-ruled]

Can you read the plug? Post a clear pic of the plug? If you can not read the timing on the plug, how about a timing light? Top and bottom ends are sealed up tight, verified? Stock oem jets, needle and a new float valve. Good premium pump gas, and check for detonation, then jet the engine. I sure hope you are running a lot of oil in the gas! Vintage Bob

 

[eagles22793]

yz125

If you can see the picture it is lean on one side and rich on the other dont know what that means but has more richness on the plug so i was going by that. I dont know how to read the timming on the plug if you tell me how I can do it and tell you?

[/IMG]

 

[whenfoxforks-ruled]

Blurry, retarded and not lean. It may have a slight head gasket/coolant leak also. Or, you are burning some really funky stuff in the tank! The grass looks good, what the heck, turn the af off?

 

[eagles22793]

I did a compression test on it and came out to 195 psi and didnt go down so I dont think I have a head gasket leak and a coolant leak dose not sound right if it is not using anifreeze. sorry about the picture. I am running the vp 106 i think with 32:1 ams 2 cycle. What else can it be or dose leaning the bike out more sound like it ill burn it up?

 

[BSWIFT]

Read thru the jetting thread and follow it closely. If you are running the stock pipe, clean filter, and fresh fuel mix your jetting should be close to the stock sizes. These bikes come rich from the factory so you will likely have to go a bit lean on the jetting to sort it out. Use the jetting thread and you will get it right. Work on the off-idle to 1/4 throttle and only make one change at a time. Use the octane of fuel for your compression not your ego. Pump fuel is not as consistant as race fuel but you may not need the high $/octane fuel to begin with. Depending on your premix oil, you may be able to go to 40:1 or even 50:1. Premix ration is NOT what determines whether you are lean or rich, the jetting is for premix:air ratio.

 

[eagles22793]

I am not running the stock pipe or silencer a fmf fatty and silencer I am afraid of using pump fuel because of the high compression head gasket and pro lite piston. I am not worryed about jetting I am worryed about blowing my bike up. I am running 32:1 because of that reason also. I just need some tips on to check a couple of things before I go to lean on jetting and end up blowing the bike up.

 

[whenfoxforks-ruled]

You did not read the jetting links.

 

[eagles22793]

where are the jetting links

 

[helio lucas]

I am not worryed about jetting I am worryed about blowing my bike up.

this is very closed related.

as i said before, read the archives. i´ll give you some links to read but be carefull, it may take some hours to read everything.


http://www.dirtrider.net/forums3/showthread.php?t=92818
http://www.dirtrider.net/forums3/showthread.php?t=108727
http://www.dirtrider.net/forums3/showthread.php?t=50053
http://www.dirtrider.net/forums3/showthread.php?t=17786
http://www.dirtrider.net/forums3/showthread.php?t=5308&page=3&pp=20
http://www.dirtrider.net/forums3/showthread.php?t=89861&highlight=tom+turner
http://justkdx.dirtrider.net/carbtuning.html

here you have it, have fun...

 

[eagles22793]

learned alot from these i am going to mess around with my bike now i know a little more about the plug reading and timing hope to fix the problem before going racing this weekend

 

[helio lucas]

good luck :cool:

 

[eagles22793]

I did look at the plug and the timing looks good but the bike still boggs on the bottom end. I have a 320 main jet 30 pilot and stock needle on the middle clip. mixture 32:1 with fmf fatty and silencer pro lite piston high compression bottom gasket. I live in delaware. Is there any suggestions on what else i can check or do. I dont no if I should throw rick jets in it to see if that works witch was suggested to me before?

 

[cujet]

I did look at the plug and the timing looks good but the bike still boggs on the bottom end. I have a 320 main jet 30 pilot and stock needle on the middle clip. mixture 32:1 with fmf fatty and silencer pro lite piston high compression bottom gasket. I live in delaware. Is there any suggestions on what else i can check or do. I dont no if I should throw rick jets in it to see if that works witch was suggested to me before?

Just my opinion from years of playing around with 2 strokes:

Every setup is slightly different. Unless you follow a specific formula and specs, your setup will differ from mine.

Therefore, your jetting, timing advance, exhaust tuning and fuel used will all be slightly different from mine. As you know, even altitude and temperature will affect these things.

My best suggestion is to follow the common tuning advice. Jet it properly. Then adjust timing a small bit one way or the other and see if you can determine a difference. A dyno may help here.

You simply cannot follow my jetting # suggestion and get a good result in a different location.

Plus the satisfaction of tuning your engine correctly will give you the confidence to do it right again and again.

Chris

 

[whenfoxforks-ruled]

Increase the premix ratio to 20:1 and rejet. Vintage Bob