My first problem with my 400EX....

Well, I had my first problem with my 2000 400EX. I went riding on Friday with my frined, he has an RM125 dirt bike. We were riding trails for about an hour and a half, then we went to a big circle track. The track was big enough to were I could get into 5th gear on the straight aways with my 14 tooth front sprocket, then I would power slide the corners in about 3rd gear. I was riding kind of hard nothing out of the normal. Well after about 15 mins of riding my quad would start to cut out in the straight aways when I was in 5th gear going fast. It was acting like it wasn't getting any gas. I pulled over and checked everything gas and oil everything was full but I put the tank on Reserve anyways to make sure it was getting fuel. I then started to ride again and it was still doing it in the straight aways. I then stopped for 15 and let it cool down. After that I putted around in 3rd gear slowly to get some air to the motor I thought this would cool it faster. I then stopped for 15 more mins and let it set. Then we went and rode trails. It started to cut out in about 4th gear pinned. I stopped and told my friend I was done for the day and I slowly rode back to the truck. I got home and stripped it down, changed the plug, the used one looked normal, cleaned the filter blew out the gas line from the tank to the carb thought it might have been blocked with something. Took the carb out and pumped the throttle and the carb shot a nice stream of gas like it is suppose to. I put everything back together. Started it in the shop sounded fine, throttle response was fine snappy like normal. I didn't ride it though. So why was it cutting out? Its not my jetting because I have had this quad for 7 months and it is fine. I have an R4 exhaust it is jetted for the KandN and the R4 I am postive it is jetted right. I thought it might be the gas but it is the same gas I always run 92 octane Amaco gas. I bought this gas in Iowa and I usually get my gas in Nebraska do you think this gas might have had some water in it? I didn't see an inline fuel filter on the 400EX does anyone recommend putting one on? Do you think it was overheating? I had oil and like I said I was going pretty fast, plenty of air was getting to the motor and oil cooler. Their was nothing blocking my cooling fins on the motor. Anyone have any ideas? This is the first problem I have ever had with a Honda.

[DEAL]

The fuel filter is in the bottom of the gas tank.

[NJ300ex]

There is no problem. You are just hitting your rev limiter. Gear your bike back up if you don't want to keep hitting it all the time.

[SUPERFLY 400]

Its your rev limiter. Hey honda400ex where at in Nebraska are you. I'm from Omaha. Maybe we can hook up?

[Blake24]

iam from Nebraska too.......
the big Kearney!!!

Guys Guys Guys, this is not a rev limiter I know what that feels like. I have hit the rev limiter before its not the rev. Is the fuel filter built in the tank or in the valve? Do you guys ride at Logan Iowa or Genoa or Hallsey? Maybe we can rider together.

Just wondering what color was your plug when you took it out?

[hetrick425ex]

what kind of air filter do you have???? how often do you clean it???
later

[oynot400]

Your carb may need a little fine tuning with the air or fuel screw. I am not sure which with out hearing it, you will just have to play with it.
I have rode over to Logan at the private quarry. I have a buddy from my ISU days that lives in Woodbine. His dad has part intersest in that quarry. :)

[Stunz]

A faulty fuel cap vent or a pinched vent hose could cause this.

This goes for the carb vent hoses as well.

[ChadEXer]

I had the very same thing happen to me when i ran a 14t up front. i was hitting the rev limiter. I didnt think it was the rev limiter and argued with my mechanic for a long time about it!! i put the 15t back on and it stopped!!

You have to remove the gas tank and then remove the petcock to clean the screen. If you get water in your gas it will plug it up. That will probably fix your problem.

VC

thanks for all your help guys I am sure its not the rev limiter but maybe it is. I mean I guess I don't know what the rev limiter feels like in 4th and 5th gear I have only hit it like 3 times in 1st and 2nd. Thanks for your help. I ride at logan alot its the only place really close to me. Its a fun place to ride I like some of the hill climbs I went on a group ride with some memebers down into the quarry it was fun. I thought about getting a membership but I guess their is a long list to wait. Anyone ride in Council Bluffs by the Bridge or the Mormon Bridge?? Thanks again

[Ex'r Marlin]

It sounds to me you checked everything that may cause it to hesitate. I would get rid of the gas you currently have in it, and add some new, "fresh" gas, maybe try 93 octane this time just to see if it resolves your problem.

Good luck!

BTW, GO BIG RED!!!!!! (I'm a big Nebraska Cornhusker fan!)

[Scott]

Mine did this during a dusty trail ride last year. And it was progressive like you describe, first only at WOT, then cutting out lower in the RPM band during the next hour or so. The outerwear didn't look too bad, but I took it off and took a test ride and it was fine. Clean your air filter and outerwear (if you have one) and see if it fixes the problem.

[yellow_ho_01]

first off, what are you running for a pipe/slip-on and air filter and jet kit. if you have a pipe,.. good filter.... and running a 165 main jet... just out of curiousity try runnin with your airbox lid off. I was having the same problem... playing around on an oval track... coming out of the corners it would cut out like it had no gas,.. it turned out to be running too rich. so try taking off the lid... if that works you can always just make a custom lid with holes and/or screens... hope it helps...

[SUPERFLY 400]

If you say its not your rev limiter then i would check to make sure your sparkplug wire is tight on your plug. To me it sounds like your spark is breaking up. But I guess I'd have to look at it before I condem anything.

Hey Honda400ex do you ride near the south O bridge (Mormon). Its not open to the public yet just helpers I think. I wanted to go down there, but I'm not a member. Have you ever been to Whitesands mx tracks near Ashland? If you want to go out and ride one weekend just PM me. Later Bro!

[optikid123]

i would say your air filter is getting clogged or your air/fuel mix needs to be adjusted
try putting back on the 15t it is probably the easiest thing to do before u take the tank off