85 atc 250 r question

[8atc250r5]

My bike was stock except for a K+N filter and ran like a champ all day long and never fouled plugs!


I put a DG head pipe and silencer on, it will run good for a while and eventually bogs and stops running,at this point it will not start.The plug comes out black and wet.If I put a new plug in it will do the above all over again.Any help would be appreciated!


Dave

[deathman53]

if its rich it will become that way. use a new plug and look at the color, black is rich, white is lean and cardboard brown is the perfect color.

[8atc250r5]

What will fix this?

Dave

[TravEX]

What oil and ratio, spark plug, and jets your running? No fouling problems before the pipe change?

Travis

[TravEX]

What will fix this?




carb jetting.

[8atc250r5]

I am running 87 octane with wal mart 2 stoke oil.I am mixing it 20 to 1.I have never messed with the carb so it should be stock jetting.I forgot to mention that it does have boysen reeds.NGK BR9ES plug 28 to 30 gap.I have never had fouling problems up until now unless water ridding.Do you suggest better oil, higher octane gas?

Thank's for the replys I appreciate it!!


Dave

[85ytz250n]

You may want to try a better mixing oil, that is the same oil that killed my z and my chain saw. I thought there wouldnt be a difference but there was a hell of a difference. There are plenty of guys that will tell you their oil is the best, i wont do that but I will say that ANYTHING is better than the crap you are using right now. Change the oil and then try the jetting changes.

Barry

[deathman53]

use bel-ray, klotz, amsoil, yamaha lube, honda gn. Those are the commonly available ones. There are other brands, use a GOOD 2 stroke oil, no snow blower or chainsaw 2 stroke oil. Also mix it 32:1(4oz/1gallon).

[TravEX]

Try running premium in it and a better 2 stroke oil. 20:1 conventional is what was recommended back in 85, but do a search for a better synthentic oil. There are a lot of great oils out there. Try a BR8ES, which is 1 level hotter than what you're using. I can tell your from experience, I run 50:1 synthetic ( Blue Marble) and stock jetting. Every trike is different, but it sounds like you're rich. My best advice is to find a good sythentic, and mix it to the ratio you prefer and then try to jet to fit that. Always jet to your mixture, and not change your mixture for your jetting. Put a full tank of what you wanna use and then mess with the jetting. You can also run a BR7ES for trails and stuff that does not require WOT riding all the time. Hope this helps.

Travis

[350xBomb]

Definately jet esecially if you put reeds and exhaust on it. And I wouldnt run anything less than supereme in it. none of that regular unleaded....

[Aussieduner]

What size main and clip position do you recomend for a stocker with pipe and K&N as the only mods ? Im running a 155 main and 3rd clip with still flutering in the mid range(85 250r).

Aussie

[crackshot]

I am running 40:1 Amsoil dominator, 140 main, 52 pilot, 2nd clip down on needle for my altitude and temp. Runs pretty darn good and not a mega-smoker. Using a BR9ES for 90 degree weather.

[atcsteve]

Bump the main jet up a couple of sizes,leave the clip alone,run your mixture at 32-1(4oz oil to 1 gal fuel),and you should be good to go!!

[bingham]

sounds like you need to change your jets out. I am getting ready to put a pipe on my bike too. good luck man