Im Not sure but somethings is differant

9 replies to this topic
  • John_Lorenz

Posted July 28, 2002 - 12:31 PM


I replaced the stock Air filter with a UNI.

Since then I do nt need to start the bike Cold with the choke.

If I try when cold, I get one Pop then its kick kick kick.

I set the Hot Start Fires right up.

I just put the bike back together started it with no Choke, stone cold bike, In fact It had not been started in 10 days


Im not complaining, I just can not believe a filter would do this.

I just cleaned the Carb and put it back, adjusted everythng.

i can only account is that now my 45 pilot is to rich, But when its running Bamm no problems

[ July 28, 2002: Message edited by: E.G.O.**** ]

  • Vanilla_Gorilla

Posted July 28, 2002 - 01:07 PM


uni filters and other dual stage filters restrict more air, causing a self-choking is not enough, however, to cause any jettingchanges while running. thats my theory.

  • Uncle_Rich

Posted July 28, 2002 - 01:10 PM


I run an UNI filter
MJ = 162
PJ = 42
F-Screw 1-1/2 turns
Needle = EKP clip 4 ?
Elevation = 1000'
its 95 deg. dew point 75 deg. humidity 75+
SUNOCO Purple 110 pump octaine
My YZ runs good maybe a hair rich

  • John_Lorenz

Posted July 28, 2002 - 01:26 PM


I am not sure about your description on dual stage. I was loking at that, You may be right though, I suspect that I may have to go back to the 42 pilot. But I thnk what is going on is the Filter is allowing it to breath cleaner, so the effect would be too rich e\becouse of the 45 pilot I had to place in it.

Thats my thoery, I may just clean the peepee out of the original and swap it just for a stupid butt test.

Unka Rich
Thanks I think I will probably go back to the 42, I will be intrested to see how the beast runs on Tuesday with the 168 main...

  • bashn

Posted July 29, 2002 - 04:14 AM


How long did you wait after oiling the filter? It takes a couple hours for all the solvents to evaporate. All my YZF's do exactly what your describing with freshly oiled filters and will in fact refuse to start at all. Wait overnight, and you can't tell one filter from another, and no jetting changes required for stock, uni, or twinair filters. Once you have sucked filter oil into the tiny carb air passages, you could could experience long-lasting carb problems until you clean it out. Moral of the story: Never start your YZF with a freshly oiled filter.


'03 YZF450 (on the way)
'01 YZF250 (for sale)
'99 YZF400
'98 YZF400

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  • John_Lorenz

Posted July 29, 2002 - 04:56 AM


OK Geez why did not I think of the Oil Thingy thing

Man I am so dumb, thanks for the advise

  • Shawn_Mc

Posted July 29, 2002 - 09:28 PM


Pray you didnt pull oil into the pilot passage. Especially if its has sat over night. Nice sticky fully dried filter oil in those little tiny passages. Get ready to buy a couple cans of contact cleaner, it works pretty good on that stuff.

Good luck bud

  • John_Lorenz

Posted July 29, 2002 - 09:52 PM


86 db 98 db, loud stinking Wobbly Ablesons,
DWF = Dual Wife Syndrom,

Now its Oil in Me carb

Im gonna move to a small town and die
WAIT I live in a small town


Man talk about getting hit by caffiene that was a rush
Got it covered shawn, thanks though

[ July 29, 2002: Message edited by: E.G.O.**** ]

  • Uncle_Rich

Posted July 29, 2002 - 12:49 PM


I dont think I ever started my bike for at least a day or so after oiling the filter, you may be on to something
Thanks for the tip

  • tuco

Posted July 29, 2002 - 02:13 PM


Shawn MC, thats exactly what I think happened to me. Oiled the filter, paper towel dried it, let it sit for a day even. Next time bike barely started only with the choke on whole time. Pulled carb and the PJ had something stuck at the end, completely clogged there. Contact Cleaner did almost nothing, had to shave a tooth pick and poke it out, everything else was good though in there.

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