The 2-stroke thread

My YZ is going to gt ridden this weekend in an Enduro, first race back on it since end of February at the Nationals, heres my 4 stroke pic from SAturdays race, I was racing with a broken rib! Hurts like hell now...

 

Here's my new Athlete page on Facebook if you get bored and wanna see some dirtbiking shizz!
Im just going to be posting mostly race related stuff on that page for my sponsors and anybody else who wants to follow up on what Im doing during my #1 National Hare and Hound points chase!
I will be adding more info and ride reports over the next couple of days. Feel free to check it out guys.
Thanks! Yes I ride 2 strokes too, I race one Primarily for the NHHA series.

 

Inline fuel filter yes or no?

 

Yes yes yes. Zero drawbacks and peace of mind. All my carb'd bikes have inline filters.

 

I don't use them, but I get race gas that is clean so it's not much of an issue.

 

Dirt can fall in if you re-fuel when the bike is muddy, like during a pit stop in an off-road endurance race.

 

i found out that my tank has a little screen deal before the petcock inside the tank. I have a few little pieces of rubber from something that's been in the bottom of my tank since i can remember. if yours doesnt have one (screen before petcock), id get a filter then.

 

I just do MX so it's not an issue.

 

I dont use them but I do clean the petcock screen on occasion, I have seen many of the plastic ones break in hot environments.

That petcock screen only lasts so long before it starts to deteriorate and cause debris to get into the carb.

If you just do regular maintenance on that you wont need any other fiters..

 

I recently checked that screen and it was in good shape. I didnt expect a screen there to be honest. I ran a filter last year but think it may be overkill.
Thanks.

 

Nice boots

 

It's nice to see a whole thread dedicated to the premix crowd.

I've been a lifetime 2-stroke rider, 24+ years of mixing fuel with oil.

My current weapon of choice is a 2012 KTM 250XC-W. I do mostly trail riding with usually my one close riding buddy. We'll spend a day cutting a trail loop, ride it for a month & change it. Rinse and repeat. Tried some trail racing stuff, but it's just not as fun as play riding and ball busting with friends.

I've got a bunch of GoPro footage I've gotta edit that I can post, but for now here's just the scooter:

 

Advice needed:
03 YZ250 running rich.
I have only three hours of riding on this bike this season so far and there is black sludge building up on the usual areas (inside rear number plate, exhaust tip and pipe to engine mount). The plug is also black.

What I know:
Fresh gas and quality oil mixed at 30:1
Brand new spark plug
Carb fully cleaned over winter, new lines and airscrew is one turn out as per specs.
Brand new airfilter which i put alot of filter oil on (Ipone spray)
The bike started first or second kick everytime, it has excellent throttle response and never stuttered once.

My first guess is that the airfilter may have too much oil on it and is starving air making my fuel air mix to be rich.

Ryan

 

is it rich on the bottom, top, or what? my 500 was running rich on the top end and lean on the bottom.. dropped the needle to the 4th clip from the 2nd (richer) and went from a 180 main jet to a 170. Since then it's been great.

Do you know the main, pilot, and needle position on yours?

 

Update: I removed the air filter and rewashed it. I had put so much iPone spray oil on it it was almost black.
I rode it for 3 hours on Sunday and there is little to no spooge coming out of the tailpipe.
I checked the plug and it was black but no carbon build up on it.

The carb has the stock jetting (cant remember the #'s right now) and I never knew you could change needle position so Im unsure as to where that is sitting. The Pilot airscrew is at 1 turn out (stock).

Im one step closer to solving this. I will update when i know the needle position.

Thanks,

 

Needle clip was in the #3 position. I changed it to #2.
Main Jet 178
Slow jet 50

 

did you get a chance to ride it around yet with the new clip position?