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Yamaha '06 YFZ 450 What the heck is going on??????????

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Just got back from Pismo Beach. The bike ran fine while I was there. Brought it home and washed it. When I started it up I noticed the pipe got red hot really quickly. So, I thoiught hmmm must be running lean...could be sand in the jets. so I took the carb apart and cleaned the heck out of it. When I put it back together and started it up it won't idle. It cycles at low rpm...It runs for 2 seconds then starts to die then runs for 2 seconds then starts to die... I have move the air mixture screw from 1 1/2 turns to 4 turns out with no change.

I did make the rookie mistake and take the TPS off. I tried to use an OHM meter to reset it but when I plug the black to ground (black) and blue to red it gives me a reading 5.8V and does not change when I move the TPS or give it throttle???

Here is another wierd one. After I took off the carburetor and cleaned it about 6 times now. I noticed when I put it back on and don't give it throttle it starts right up and idles perfect!!!!! THEN when I give it gas the idle goes way up. So I back off the idle screw to try and bring it down and it dies. When I restart it it won't idle and it goes back to the rough cycleing on...off...on...off again. It has a 42 pilot jet, needle in the 4th position.

The thing is it ran fine until it took off the carb and cleaned it.

PLESE HELP ASAP!!!!!!!!!!!!!!!!

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I had this problem with a 04 kx250f, turned out the exhaust had some obstruction in the way. It was super weird. How is it running now? Im sure you've figured it out.

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Please stop working on your quad until you have a plan and a manual. You are not helping your cause any. It sounds like you need to take it to a dealer and have the TPS reset to correct your idle. As for jetting for Pismo, you didn't specify if you had a pipe or any other mods, but here's my recommendation: if your quad is near-stock or stock (a pipe and stickers does not make it "highly modified") then go with a 168 main, 45 pilot andleave the rest alone. Since you say the needle is on the 4th clip, you must have an aftermarket needle, since '06's do not have on stock. As for the glowing pipe, they ALL DO THAT! Stop looking at it if it bother's you.

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Found the problem!!! It was the switch in the throttle. Grounded the wires to each other and it runs great. I got to know the mechanics of my carb pretty well during this "excersise", and I enjoyed tuning it. While I was tuning the carb I got the air screw dialed in just right and that got rid of the red hot pipe! It runs much cooler now. I want to try a smaller main jet than what you are suggesting. A 145 main might be my next move.

Zookeeper, I finally reset the TPS myself. It takes time the first time but know I've got it. Trouble shooting takes time... I Don't give up. There is a reason something is making the bike run out of spec, and I just need to find it. Electrical problems can be the most difficult to diagnose, but anyone can do it. One reason I own my bike is to work on it myself so I can learn about engines and suspension.

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Please stop working on your quad until you have a plan and a manual. You are not helping your cause any. It sounds like you need to take it to a dealer and have the TPS reset to correct your idle. As for jetting for Pismo, you didn't specify if you had a pipe or any other mods, but here's my recommendation: if your quad is near-stock or stock (a pipe and stickers does not make it "highly modified") then go with a 168 main, 45 pilot andleave the rest alone. Since you say the needle is on the 4th clip, you must have an aftermarket needle, since '06's do not have on stock. As for the glowing pipe, they ALL DO THAT! Stop looking at it if it bother's you.

Dude settle down, you obviously have just been proven wrong.

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Dude settle down, you obviously have just been proven wrong.

Jake...Thanks for the support, and suggestion to check the pipe! These message boards are awesome when people offer sugestions other that take it to a shop. I did have a mouse crawl inside a TT-500 silencer years ago and the bike would not start. How random is that! Took the silencer off and it started right up. Trouble shooting can be frustrating, but it is always rewarding

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No problem, I always found going to the shop kind of demeaning. If I own a bike im going to do everything i can at home to try and fix it before I go spend however much to find out it was a 2 minute fix. That is crazy! haha...wow...was is still alive?

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Why do people trip when someone wants to work on something themselves?

i dont understand...

You save so much money AND get a kick out of doing it yourself..

Its all part of the sport/ hobby.

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No problem, I always found going to the shop kind of demeaning. If I own a bike im going to do everything i can at home to try and fix it before I go spend however much to find out it was a 2 minute fix. That is crazy! haha...wow...was is still alive?

The mouse crawled out of the pipe coughing and weezing. The poor little guys hair was smoking and sticking straight out. This happened about 20 years ago, so he has probably passed on by now. The last time I saw him he had the neighbors cats licking him and cleaning him up. I don't think he understood when they told him that they wanted to clean him up for dinner.:bonk::bonk:

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