Lucas Octane booster?

[1998RM250]

yessir,thank you all... I called suzuki and I was right on with the stock jetting, my "tuner" was not however. Just dont understand how he's trying to tell me it didn't have the stock jetting, when I seen it with my own eyes and wrote everything down. Funny part is he's getting mad over it, and won't return my emails anymore! I'm going to put it back to stock, I want my $100 back too since he did the job incorrectly!

 

[Patman]

How exactly do you determine he did the job wrong if you don't understand how to do the job yourself? :think:

 

[ellandoh]

3days, 3pages and were still stuck on stock jetting for a possible pinging....wheres Pred to get this thing shipped out??

 

[Patman]

IF (answer) != (desired answer) THEN repeat...

 

[_JOE_]

And we wonder what's wrong with the world today?

 

[Patman]

I don't wonder it's pretty obvious to me.

 

[Ol'89r]

See! Even this thread has lost it's spark. :whoa:

 

[Wolf]

buzz killer

 

[1998RM250]

I know how to jet the bike, I just wanted other people's advice as well... Once again I only sent it to this guy to jet as I figured he knew more then me, when he didn't even know what the stock jetting was to begin with and messed it all up. If I had the jet's I'd be out there right now doing it, but they are on order so in the meantime I'm just asking for advice from you people with more experience. I know how to build motors, especially the GM LSX blocks, and have working on things most my life. There's no need to repeat myself on here even though I have a bunch of times, I admitt I don't have much experience building two stroke motors besides top end's etc but I know a good running motor and understand about the optimal a/f ratio especially when I work with turbocharging cars. No need to knock on me because I want to learn more, I know these forums are kind of dead lately besides the typical questions, but please don't pick on the guy who actually want's to learn things.

Edit: I took the carb apart because I got tired of waiting to hear from this guy, he's got a 160 main, 48 pilot, and a 45 power jet. All he did was drop the main jet down one and put an 03' N8RH needle which he "thought was stock". Going back up to a 162 main and see how it works with this needle, then going to try the stock needle after.

Only thing is today before I took it apart, I started it with the choke on and it was idling very high. Turned the choke off and the idle went back down, pulled it back up and the idle went way up again. Which way do I turn the choke knob to lower the choked idle? Thanks for dealing with all my questions, I really do appreciate it and I hope you guys accept my gratitude. :worship:

 

[ellandoh]

Which way do I turn the choke knob to lower the choked idle? Thanks for dealing with all my questions, I really do appreciate it and I hope you guys accept my gratitude. :worship:

this is something ive not heard of?? thought the choke is up or down thats it.

and i dont believe anybody was actually bagging on you specifically , if they did im sorry for that, as i may have started it off. i figured you got what you needed from this thread and it was a good a time as any to get some bonus round entertainment :)

 

[1998RM250]

Its all good, I know I ask alot of questions, I just want to make sure everything is done right. Hmmm I know if you turn the choke knob on the pwk 38mm its also the idle adjust, but I heard it's just the choked idle and the other idle screw is the normal idle.

 

[whenfoxforks-ruled]

MX bikes idle? Vintage Bob

 

[ellandoh]

MX bikes idle? Vintage Bob

mine does

 

[_JOE_]

I never had much luck with the choked idle adjustment on my 02. No matter what I did with it it still idled high on choke. It only had to be choked for about 10 seconds though then it idled fine off choke.....

 

[whenfoxforks-ruled]

Famous parting words, I know. No really, I know. But really, I know. I know?

 

[Someone]

mine does

None of mine ever did. Always have to blip the throttle to keep her running if sitting still for more than a few seconds.

There's no stop signs in the dirt. :fft:

 

[Ol'89r]

Thanks for dealing with all my questions, I really do appreciate it and I hope you guys accept my gratitude. :worship:

Thanks for playing along 1998RM250. Sorry if I muffed up your post with my Lucas comments. ;) It was a little side joke that you have to be older than dirt to understand. Most of the guys that got the joke have graduated from motorcycles to walkers years ago. :laugh:

Do a search on the name, Joe Lucas.

Also known as the Prince of Darkness.

It was once said, "If Lucas made guns, there would be no wars." :nod:

 

[Roope]

If you look at the Lucas MSDS sheet for the product you'll see that the product is MMT based.

MMT = Methylcyclopentadienyl Manganese Tricarbonyl

It's an organmetallic fuel additive used to replace lead and raise octane (mainly RON). This is important because two-strokes usually need and increase in MON to squelch knock. How would this work in 4-stroke I have ktm exc-f 250 and th

MMT has zealots both for and against it. As far as I know it isn't used in pump fuel anywhere in the US, but I believe it is used in parts of Canada. The metallic deposits tend to shorten plug and oxygen sensor life, so in a world of 100,000 mile tune up expectations it's unlikely you'll ever see it in US pump fuel.

MMT tends to be less effective at boosting octane as the percentage used increases, and the deposits get much worse as the percentages increase. So it's definitely a case where more is NOT better.

If you look closely at the pictures attached you'll see the electrode edges are really sharp on the plugs even though the deposits are fairly heavy. All those deposits were built up in just over an hour, running about 2 oz/gallon of high percentage MMT based octane booster in a YZF four-stroke that was jetted sharp.

It's actually a pretty good additive if all you want to do is add a few octane points protect your engine from knocking in a pinch, but it generally makes tuning a total nightmare, and comes with some significant side effects on a two-stroke.

Reading plugs with this in the fuel is next to impossible. In a two-stroke the deposits can easily lead to hot spots in the combustion chamber increasing the chance of pre-ignition.

Here's a thread that has some info on a couple of boosters I tested with for reference: http://www.dirtrider.net/forums3/showthread.php?threadid=15450&referrerid=16241

You would be much better served adding a small percentage of leaded race fuel or even AvGas to your premium pump fuel to raise the octane rather than using an additive like this.

how would this work in 4-stroke? i have 2012 ktm exc-f 250 and thought would try some additive.

 

[Rich Rohrich]

It's unlikely that you need additional octane for this engine. Is there another reason for you to go to a fuel additive?

 

[Roope]

It's unlikely that you need additional octane for this engine. Is there another reason for you to go to a fuel additive?

a bit better performance and throttle response.

 

[Rich Rohrich]

a bit better performance and throttle response.

You will get neither just adding this to the fuel. Higher octane does not add performance, and additives from a bottle will rarely improve throttle response, they tend to muddy up the response.

A proper race fuel designed for a high speed four-stroke and subsequent jetting to match the fuel curve to the new fuel, will get you what you are looking for. It costs more and requires more work, but that is true of most good things.

No magic bullet to be found in a bottle at the parts counter, sorry.