one54ton

i just picked up an old kx 250 for a beater/sand bike. id like to get schooled on 2 strokes.

s cesnick

Well, It depends on what kind of riding/racing you are into. I race Harescrambles/GNCCs on the east coast and www.woodsracer.com is a good harescramble forum but it is mostly east coast, ( but all are welcomed of course) 2-strokes are always discussed.

What year KX?

matego

dirtrider.net is where I go when I have questions. Welcome to the wonderful world of 2 strokes Do yourself a favor and educate yourself on correct jetting before you go chasing your tail thinking it is other issues. A clean jetted 250 is a animal, no matter which brand and will keep plugs clean and start right away with good compression. Have fun and enjoy!

s cesnick

That is true. I haven't fouled a plug since i don't know when. Jetting and mixing oil correctly is the key. It also gives the bike that nice crisp throttle response.

one54ton

the bike is a 92...starts in 2 kicks COLD. ive been using Motul mix at 40.1. I have noticed some sludge coming out of the exhaust and onto the swingarm that is a pain in the butt to get off. my friend has an 04 cr 250 with the same mix...no sludge...what gives?

matego

Its called spooge, usually from being jetted too rich. You need to learn how the individual circuits work in the carb and how to feel lean from rich. Do you keep your throttle pegged the whole time or run mid-throttle? Does it feel boggy or light/higher revving at any given throttle setting? Its kinda hard to explain but once you feel it, you will know. When it comes to jetting, you need to start from the beginning with the idle circuit. It goes Idle adjustment/air bleed, pilot jet, needle then main jet. Get base measurements like screw settings and jet sizes and start playing. It wont take long to feel the difference between rich and lean. For your main jet you need to do a plug chop and see where your carbon ring is. Do lots of reading and dont be scared, between s cesnick and myself, I am sure we can help you jet it. I am sure he knows a trick or two to help out.

one54ton

thanks a bunch...im betting that my plug is bad as well...is there a how to guid to re-jettting my bike...i like pics

matego

Here is a ton of info for ya. You will probably be more corn-fused after reading all this than you are now.
http://www.dirtrider.net/forums3/showthread.php?t=42618

Its not too bad, maybe I can do a video of it if you are still not sure. I need to tune up the bike for a hillclimb on the 3rd anyway.

rip 112

Thats why I run 4 strokes, I ride frequently and don't have time for mixing oil and cleaning plugs. I've had 2 strokes but for what i use them for they aren't best suited. Had a friend with a Service Honda CR500 2 stroke, kept it in his house in the bedroom, rarely ridden but I have seen it run, its absolutely nuts!!!

s cesnick

If you didn't have time to mix the oil and check a plug on your old 2 stroke, I would think it would be safe to assume that you are not checking your valve clearance on the 4 stroke. I raced a 4 stroke for a period of time a few years ago (YZ450f) and I will tell you this, It is'nt a matter of IF it will grenade on you, if is a matter of WHEN. especially if the valves are not being checked and the air filter is not attended to on a regular basis.
I check mine religiously, cleaned the filter constantly and never rode on the rev limiter ( which is a very popular thing to do with the younger crowd) and mine still went belly up.

Rebuild for a 2005 YZ450f------ $1,900
Rebuild for a 2007 YZ250------- $250

That is why I went back to the 2 smoker along with most of my riding/racing buddies/.

rip 112

Haven't had to rebuild yet! I do check my valve clearance, I do clean my carb and air filter on a regular basis, tighten chains, blah blah with all the money I've spent on toys, I'm not so stupid that I would run them into the ground and say "oh well, buy a new one". These toys are just as expensive to mod and tinker with as these trucks are.

the other thing is that since i broke my clavicle, i've stopped track riding and diverted my attention to trail riding. Listened to everybody tell me the YFZ wouldn't make it as a trail ride, but after 3 yrs of hard abuse and southern engenuity, it runs stronger than ever.

My WR250F has been hydrolocked twice, layed over, straight abused and it runs like a champ. It has been serviced right and still doesn't need a rebuild, carb tunes in good, no smoke whatsoever, barely uses any gas at all.

Maybe its just I have really good luck, or Yamaha is worth every penny, but out of everything else I've owned, the Yamas have been the greatest.

s cesnick

I just realized that your 450 is a quad. I'm not sure that they are as touchy as the YZf of not. Maybe the timing has been retarded a bit for the quads. I'm not sure. It used to be common practice a few years back.
Yes, for some reason the 250f's are not as volitile as the 450's and can take ALOT of abuse.
I also agree that Yamaha makes a quality product. I have owned quite a few of them but nothing compares to the KTM's in quality. Unfortunately you pay dearly for that quality and it just isn't worth it anymore when Yamaha make s a very nice bike for a few grand less...

rip 112

Yeah, its a quad, and it has been tinkered with. I can run with my buds CR250. Right now its in the shop getting freshened up for this summer. You can say its a sleeper, cause I'm too cheap to buy something for it that won't make it faster! It is pretty touchy, but the 2 extra wheels help stable the power better. It is an absolute blast!

I do like KTM, but as you said they are pricey and i could never justify the costs. I've kinda stuck with Yamahas also because I have an account with the local dealerrship and get some good discounts. Plus i can get everything from one place.

matego

I came within a quarter inch from getting a new CR500AF from Service Honda. I was mad that I couldnt climb the hills as good as the 450's and CR500's. I decided to send my jug and head to Eric Gorr and have the 265 kit put in. It really made the engine work everywhere, bottom to top. I am just old school and love 2 strokes. I feel 4 strokes are for quads and farm tractors but that is just my opinion and I have been proven wrong by many YZF and CRF 450's over time. 2 stroke for life! Ring ding ding ding!!! That WR you ride is a awesome all around bike. I would add one to my stable just like the XR400. They dont really set the world on fire with performance but they are bruisers and WILL get you home at the end of the day. When trail riding 40 mi. from the hard road that is critical.

one54ton

im loving my 2 stroke more and more!