36 replies to this topic
  • MichaelAngelo

Posted April 30, 2002 - 12:48 PM


Sorry Boyz,
Didn't realize that I was opening a can of worms with this post. I was just curious about going bigger. It sounds rather simplistic, and it is, but I figured more gas to the piston the faster it would go. I have the wr timing, the bike breathes well with the T4 complete exhaust system and lid removed, and I was just wanting an edge over my buddy. I was just concerned about the possibility of squirting too much gas in there and causing valve damage. Seems nobody responded to that concern.
Thanks for all the interest though.

  • S_Phillips

Posted April 30, 2002 - 04:20 PM


Hmm I'd like to hear more on that one to, I'd never heard to much would cause Valve Damage?

My thoughts on going bigger would be ok but it wouldn't do anygood unless your getting more air in there to. The plug would tell all I think.

  • Rich_in_Orlando

Posted April 30, 2002 - 04:27 PM


I'm trying to get this part straight. How could running too rich cause valve damage? Carbon deposition on the valve faces to the point where they don't seal anymore? Is over-rich valve damage something that happens commonly?

  • Mark_Cantrell

Posted April 30, 2002 - 05:48 PM


MA, here is my response to the 180 main jet (help) post. I'm pasting a copy here because it came up again.

Dude, I can't agree with your basic assumption. The bikes run best when lean. Most people that I respect here (and a couple are replying to this post) agree on this. I am thoroughly convinced from my tests and experience. More gas (after this healthy lean I'm describing) just makes it too rich, reduces the snap and robs the power. Way too much causes carbon deposits on the inside of the engine, plugs the spark arrestor, and fouls the plug.

The down side of lean is that it makes it run hot. The leaner the hotter up to the point it starts missing (you would hear rough running or popping at that point). The heat of too lean, combined with running it hard, can cause catastrophic engine problems related to melting holes in the piston and burning valves.

You are jetted correctly when lean enough to get the max power and snap but not so lean you damage your bike. The factory, not surprisingly, errs on the safe side, too rich. Too rich on the pilot, too rich on the needle, too rich on the main, and too rich on the AP. They know the savvy riders will correct this and the not so savvy ones will not hurt their bike.


  • AK-thumper

Posted April 30, 2002 - 08:56 PM


I have no idea what stock jetting was on a 2000. Maybe if you posted the rest of the carb settings you will get more detailed suggestions. Is your bike YZ timed? BK modded? Maybe a little history as well. Why did you put the 175/180 main and/or 48 pilot in? Was there a problem? Maybe you should go back to the way it was.

"Popping" is not very descriptive. If it is loading up and misfiring or backfiring repetitively you are rich. Typically this is accompanied with rough idle, viscious bog, and fouled plugs. If it is actually exhibiting a lean pop something is plugged or leaking air because your jetting shouldn't be lean with a 48pilot/75PAJ.

My humble suggestion:
1. Clean carb and install stock jets, set float level
2. Check for air leaks & verify good compression
3. Check coil & CDI using shop manual
4. Install new plug and see how she runs

JD & Taffys suggestions will work for you. I have worked off both of their baselines and been very pleased with the results. Quality free advise is hard to come by in this world. Enjoy it while it lasts.

  • Guy

Posted April 30, 2002 - 10:34 PM


neWRiver, it just amuses me that you are so voiciferous in your damnation of Taffy, yet you go out of your way to have an argument with him.
Your opinions are no more (or less) valid than his, whether you agree or not, he does know what he is talking about!
"quit bleating" was more telling you to stop complaining rather than to "Shut Up" as far as I'm concerned it's an OPEN forum for people to cast their opinions, BUT stop dissing Taffy for his mannerisms,
In this day and age of "Brown Nosing" and "The right image" etc etc it is refreshing to find someone who speaks as they find, and doesnt flannel people!
Mark, didn't take Taffs comments to heart, perhaps he has worked out his "Bark" is worse than his "Bite", so WHY oh WHY are you getting all worked up over his attitude? it wasn't aimed at you yet you seem to have taken it as a personal insult that Taffy finds it frustrating that he cant get his message accross.


Posted May 01, 2002 - 03:43 AM


Some of you would be well served by listening to what Taffy has to say concerning jetting. The Taffster can seem quite abrasive at times (But from experience most of us realize that it is just his nature and not a personal attack). There is an old saying that a couple of you should well heed.

"Better to be thought a Fool, than to open your mouth and Remove All Doubt."

Bonzai :)

  • neWRiver

Posted May 01, 2002 - 09:25 PM


Guy, so let me get this straight. I should stop "dissing" Taffy for dissing people. Sounds fair. :)

BTW, what comment did I direct at you that caused you to jump in and take this personally? Seems that you feel insulted by something I've said to someone else altogether (think about it).

YAMAKAZE, good advice for the man in the mirror as well. :D

Look, this may seem counter productive or possibly "sacrilegious" to some avid jetting students. Some may even fear that the jetting gods may be angered and not smile down upon us anymore. Frankly, I can't even imagine that anything I could say would make Taffy "go away" and neither is that my intention. I am interested as well in the vast amount of jetting experience that has been shared by many here and Taffy is certainly a significant contributor from whom we all have tried to learn.

So why should I care if someone wants to lick someone else's boots in exchange for some scraps of jetting advice? I don't know. What difference does it make to me if a certain person takes every jetting discussion here as if it were either a test of his knowledge or an assault on his preachings? Not sure.

Foolish, I guess. I just like to have ALL the facts.

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed

Posted May 01, 2002 - 09:46 PM


Newriver = Oxygen Thief! :)

Bonzai :D

  • Mark_UK

Posted May 01, 2002 - 09:57 PM



just remember,,,"I T S O N L Y A C O M P U T E R"

  • Guy

Posted May 01, 2002 - 10:13 AM


Originally posted by neWRiver:

BTW, what comment did I direct at you that caused you to jump in and take this personally? Seems that you feel insulted by something I've said to someone else altogether (think about it).

:D I have taken NOTHING personally, I'm trying to illustrate the point of how irritating it must be when someone jumps in and condems your actions when they had nothing to do with the discussion in the first place.
You have made your point that YOU find Taffy's manner too abrasive for you, fine , no problem, so dont enter into discussions with the man, above all dont assume that everyone agrees with you, Some people may find YOUR attitude annoying in the extreme, you wouldn't want people jumping on your case everytime you post your opinions would you?? :)
As for your "boot licking" comment well, that would almost be funny....if it weren't so sad :D
Lighten up, and remember, it takes all sorts to make the world happen, not just what one individual would like.

[ May 01, 2002: Message edited by: Guy ]

  • Chaindrive

Posted May 01, 2002 - 11:02 AM


"The reasonable man bends to the will of the world and accepts what he cannot change. The unreasonable man tries to change what he cannot accept. Therefore, ALL progress depends upon the unreasonable man." ...or something like that?

Let's all be unreasonable. :D :D :)

"The British and the Americans are two peoples divided by a common language."

Thank God for the Aussies and Canadians! :D

  • Guy

Posted May 01, 2002 - 11:11 AM


:) LOL! :D :D

  • neWRiver

Posted May 01, 2002 - 11:24 AM


Originally posted by Mark_UK:

just remember,,,"I T S O N L Y A C O M P U T E R"

No,,,"I T S O N L Y A C A R B U R E T O R" :)

  • Mark_UK

Posted May 02, 2002 - 04:30 AM


roll on fuel injection,,, then taffy and new river can kiss cuddle and make up

  • yamaha.dude

Posted May 02, 2002 - 03:23 PM


I think this has run it's course, and now we can all get back to our regularly scheduled lives, bearing the folllowing in mind.

1. If you don't like someone elses jetting recommendations, then work it out for yourself by trial and error. then let us all know what you found.

2. If you have no idea where to start, then use the search button. Or read peoples signature block.

3. Everyone has opinions, and each of us are entitled to hold them and defend them, but not at the expense of personal attacks and provoking of arguements. there are plenty of alt-dot newsgrousp to do that stuff on.

4. TT'ers appreciate the time taken by others to explain answers to the questions that are asked... Some times over and over...

This post is now over, end, finito, finished...


[ May 03, 2002: Message edited by: Bill ]


Posted May 02, 2002 - 04:16 PM


OOP's , This is a test of the CLOSED TOPIC SYSTEM...

Bonzai :)


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