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2008 Honda TRX450ER

  1. i got the bike and it was not running the best. I cleaned the carb and put a new carb kit in it. And it runs good now. I have an oil leak for the three way breather line, my question is as to why I have oil leaking out of this line? I really do not under stand the purpose of it either? One end comes from the left crank case, another from the cylinder head cover and then the top part on that t goes to my air box.

    Also as I was riding it seemed to cut out in fifth gear like it may have been cutting out in the top end of the rpms. It definitely was in fifth gear but just got it home as I saw that I was leaking oil out of that breather hose. Any clues on that would be great as well.
  2. Generally, lots of oil from the breathers means lots of blow-by at the piston(s). Hopefully the engine is just tired, worn rings and cylinder wall; not a cracked piston or gouged cylinder that has to be replaced. It would be nice to get compression readings, but if this has a kick-start then it probably has a compression-release that makes taking compression tricky to do.

    As to the misfire, what does the spark-plug(s) look like? Post pictures...
  3. It is an electric start and I figured I would do a compression test on it when I get back to town next week
  4. I will also post pictures next week of the spark plug for you
  5. So I did a compression test and the reading came out at 35 psi. Then did a leakdown test and I got like 62% leakdown reading and it all felt like it was coming out of the carb. I had rotated the engine clockwise several times to see if I wasn't on TDG to get a proper reading but it didn't matter how many times it always had the most air coming out of the carb. I have a clymer repair manual that helps with some stuff just trying to get opinions. I was standing on the right side of the four wheeler when I was rotating it clockwise. I hope this is the right direction. I did feel a very small amount of air coming out of the exhaust but couldn't feel any coming out of the breather hose. I am wondering which direction to go now that I know this. Also I have a picture of the spark plug below.
  6. Take a peek at the valves as they open/close while rotating it by hand. Even though this has electric-start, it may still have a compression release while cranking. What I noticed when going through this type of investigation (a Honda 200cc) was that the exhaust valve would close at the normal time (crank angle) but would re-open briefly part way through the intake stroke; not the normal exhaust/intake over-lap.