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Yamaha IT 450

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I recently acquired a 1979 IT 450, (it was bored out) and it never had the power I always thought it should have. Couldn't even get it to wheelie. So a friend came over and rode it around and said, "Your clutch is slipping!" He turned the clutch adjustment almost all the way in on the clutch handle (instead of all the way out like it used to be), and I hopped on the bike and preceded to almost flip myself over backwards! I was stunned at how much power it "now" had! I never even thought that it could be as simple as having your clutch lever adjusted the wrong way. Anybody else have this happen to you? :thumbsup:

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I've never ridden dirt bikes much, and I couldn't tell whether it was slipping or not. Now that I know what it does feel like, I'll be aware of it in the future. Come to think of it, I don't even know how I didn't know it was slipping! But now I know.

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I've never ridden dirt bikes much, and I couldn't tell whether it was slipping or not. Now that I know what it does feel like, I'll be aware of it in the future. Come to think of it, I don't even know how I didn't know it was slipping! But now I know.

Ok, that makes sense. Now go tear it up. :busted:

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I sure would like to tear it up, but now it's having ignition problems! :busted: Weak spark, can't start it for nothing. And I'm kicking it REALLY hard. I can pull start it using my dad's jeep, but it won't kick start. It has a really weak spark, so we (my dad and I) tried a bunch of stuff but nothing seemed to help. I might end up taking it to a local mechanic friend of mine and see what he can do.

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Mathew , just keep an eye out , or is that an ear ? To you clutch plates . You dont know how long this has been like this and the plates and pressure plates may be fried . I had the 400 and it just stood strait up in the first 3 gears , everytime you twisted the throttle , it was so much fun . Untill I got arrested for dangerous driving , ha ha . greg

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try changing plugs and checking the plug gap, also check the plug wire and cap to see if the insulation is cracked and maybe exposing bare wire, and depending on the year of the bike it may have points that need to be cleaned

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Definately start with a new properly gapped plug and also check that spark plug wire as Sasquatch said. My IT 200 had spark when I bought it but after a while it got weaker, then intermittent, and then no spark at all. I finally traced it down to a bad source coil. Check the easy stuff first though! Rickystator hooked me up with a source coil for less than half the price of an oem part, their customer service was really good.

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I never use the clutch other than starting in 1st and finding neutral, so that hasn't happened to me, but...

Yesterday I had to leave work in a hurry to go get my Jeep/trailer so we could move a large printer across campus without trying to lift it into the dept. truck. I got to the first stop light, and there were hoards of young lady students at the corner, I'm feeling pretty fly for a white guy, as they can't tell it's an old goat under the helmet. Light turns green, give it some gas and it bogs down. I realize in my hurry, I didn't turn the petcock on, turn it on, and rev it a little to keep it running while the gas seeps down. as soon as she smooths out a little, I want to go, trying not to look like an idiot/block traffic/miss my light. Not realizing she's was still starved for gas I gas it, release the clutch, and at that instant, she gets all the gas she needs, wheelies up good. Not the cool kind of evil grin wheelie, but the feet dragging behind you terrified expression flip over and lay on the street kind of wheelie. I don't know how it didn't flip over or how i got back on the seat, but it was uneventful. Security was right behind me, thank God for veteran tags! Who would mess with an old vet on an old ratty bike on a 40 degree cold day?:busted::bonk::busted::lol:

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i use my clutch when shifting most of the time because it shifts smoother and id rather replace a clutch than shift forks or something more serious i actually told my dad to make sure to use the clutch when shifting my bikes because he never did on his cruisers

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I took my bike up to a friends place today, and he tested the spark. It wasn't perfect, but it was good. He got on it and started it in about 3-4 kicks, (made me feel stupid), and we went riding together for a while. After about a half hour break, we tried to get it started again, but it wouldn't start. Finally push started it. I'm going to try changing the oil that I mix with the gas to a higher quality synthetic oil and hope that helps. It's really weird because it has good spark, and I'm kicking it good and hard, but it just seems very finicky as to when it wants to start. The only thing I can think of is maybe the floats aren't adjusted right and it's flooding out the engine, or I need a new needle in the carb, or a need to switch from the junky oil I was using to a higher quality brand. I hope one of those works.

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