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First post, a couple questions

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Hey guys, i'm new to the forum and would like to introduce myself. I am a superbike rider/racer turned offroad fanatic. I've been riding and racing superbikes of various makes (Aprilia, Honda, Suzuki, and Ducati) for about 12 years and am just now getting heavy into the off-road thing. I am a motorcycle tech by trade and do a lot of chassis/suspension setup on the roadracing side of things.

My first bike ever was a 2-stroke, an Aprilia RS50 I had inherited from my older brother when I was 14. I later inherited his RS250 (that thing RIPPED!), before moving into supersport on 2 different Honda 600's and eventually to superbike on a GSXR1k, which later became a turbo street beast while I was attending MMI in Florida. I now ride and track (no longer do any serious racing since having a baby) a 2008 Ducati 848 that's built to the hilt with all the Ohlins, Brembo, Marchesini, etc goodness you can imagine. I love it and will never give up street riding, however I have a newfound love for the dirt.

I have only owned dirtbikes since last summer, when I bought an old CR80 just to play with and an 02 RM125 to ride with my buddy that races GNCC and is way better than I am. I sold both of those over the winter to invest more into the Duc, and of course now that summer is here again I've bought another 2 dirtbikes, this time a 1989 KX80 for my fiancee, and a 2002 YZ250F for myself.

Is the YZ250F a decent bike for someone just getting started in the woods/MX scene? I've read and seen in my shop that they seem to be more reliable than other 4-strokes, which is why it was my first choice. The bike I bought is in excellent mechanical condition, I've checked it all over and everything looks pretty much as good as one could expect on a 2002 model bike. It fires on the first or second kick and runs like a beast. Did I screw up buying such an old bike or would I have been better served to buy something brand new? I paid $1500 for the bike. How much has changed since then and is there any real noticeable difference (atleast any that are worth the $4k price difference) to a new rider between a bike of that vintage and a newer model? I am just learning to ride in the dirt and won't be winning any motos anytime soon.

What are the necessary mods to the early YZ-F's? I've heard of the autodecompression mod, but frankly I dont think I need it as I dont even use the decomp lever, just kick it and she starts right up. I know suspension will need done eventually but it just got new seals and I figure ill let them fail before I go tearing into it. Is there anything else that really makes a huge difference to the overall experience? It needs an aftermarket exhaust but that can wait until I find a deal on eBay (anyone got one for sale?). I heard 2006 stock exhaust cans bolt up and are less restrictive, is this true?

Anyway thanks for all your help and your forum rocks.

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One thing i have noticed is that when i put the bike in gear and pull the clutch and rev it it lurches forward a bit as if the clutch is dragging. I pulled the cover and everything in there looks brand new, no grooved basket or worn plates or anything. it seems to get better as it warms up but never completely goes away. i'm going to pull the pressure plate and make sure it's not warped but i highly doubt it based on the condition of the other parts. is this a common problem? i tried the "washer mod" i read about on another website but it didn't do much if anything. free-play is correct and i can't for the life of me figure out what is causing it...

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One thing i have noticed is that when i put the bike in gear and pull the clutch and rev it it lurches forward a bit as if the clutch is dragging. I pulled the cover and everything in there looks brand new, no grooved basket or worn plates or anything. it seems to get better as it warms up but never completely goes away. i'm going to pull the pressure plate and make sure it's not warped but i highly doubt it based on the condition of the other parts. is this a common problem? i tried the "washer mod" i read about on another website but it didn't do much if anything. free-play is correct and i can't for the life of me figure out what is causing it...

This is quite common, especially when the bike has heavy duty clutch springs and aftermarket plates. To be honest I wouldn't worry about the clutch, Just go ride... 👍

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thanks.. i appreciate it. i can't wait to actually ride this thing somewhere decent. ive just been ripping it up and down the alley. it sure is more user friendly than my old rm125 👍. the power is just everywhere.

did i get ripped off or is 1500 a decent price? it was either this or an 03 yz125 for 1200. i just didn't feel like mixing gas any more and am way more comfortable on the 4-stroke. hopefully i got a good deal but honestly i did zero price research before buying.

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what year exhausts are interchangeable with the '02 model bikes? i'm looking for one on ebay and none seem to be for the 02's.

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If it were me, I'd save some money and invest in new valve springs and cam chain. Those 2 components have a definite life and will ruin you decent deal. While your in there, check the piston and rings.

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Each year Yamaha made improvements in their bikes. My 09 does everything better than my 03 and I had 06 and 08. The alumnium frames turn quicker than the steel ones, and the twin chamber forks are better. When you get around to checking the valve and have to adjust them check the shims. The shim thickness that will give you a indication if you need new valves. I believe when the bike is new the shims are around 178to183. Do install the auto compression, and if it does not have it a adjustable fuel screw, booth will make the bike much easier to start especially when you are in a hurry like chaseing your buddy down a tral and you droped the bike and try to restart.

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The washer mod to your clutch helps greatly. Easy to find neutral while running. Starts while in gear now too. You don't realize it until you struggle with it a few times on the trail.

You may just need to adjust the clutch lever to prevent the lurching or install a longer clutch clutch actuator detailed here:

http://www.thumperfaq.com/clutch_mods.htm

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it seems to go away after the bike warms up. i've done the washer mod and that didn't really seem to make a difference. i'm going to deal with it until it's time for new plates, then go with moose plates, which i hear help out a lot.

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