after i get my 400EX i'm gonna break it in of course. i wanna ride so bad and its gonna be hard to resist just goin out and shreddin. so i wanna get my baby broke in as fast as possible. will riding it around with no more than 1/3 throttle thorugh 1 tank of gas be engouh break in time or do you think i should just go a little longer? and i've already searched for this and nothing came up and i thought that was weird cuz i know i've read topics about this before. so anyways if you can help me out really quick i'd appreciate it.

 

When I rebuilt the engine in my Foreman I waited till I put 2 tanks of gas through. Then after that I adjusted the valves and rode it like I stole it.

 

1/2 a tank of fuel at varying throttle positions-avoid full throttle. Then let it rip. Adjust the valves after about 10hrs. I always heat cycle them too. Start it, warm it fully, shut it off. Wait for it to completly cool, then over again. Then the 1/2 tank rule. 400ex motors will work fine no matter what you do.

 

I don't remember the 4stroke break in schedual.I'll look around and see what I can find.

 

I would do what the owners manual says as far as breakin. I would do a oil and filter change after first day of riding. When you change filter for the first time pull apart the pleats and see what it has caught. No need to have all that microscopic metal swimming around your new motor that the oil filter doesn't catch. Gosh Yellow just looks good on a 400EX. Chet

 

Hey Juggalo,This is recommended by Duncan.

PART I (3-Idle periods, 3-Cool down periods)

IDLE: Start engine and let idle with a fan blowing on the front of the engine, to simulate Tiding type
conditions without a load on the engine. Let engine idle for exactly 10 minutes.
COOL DOWN: Shut engine off after 10 minutes of running and let machine cool down for a minimum
of 30 minutes. Let fan continue to blow on engine.
IDLE: Repeat first step
COOL DOWN: Repeat second step.
IDLE: Repeat first step.
COOL DOWN: Repeat second step.

PART 11 (6-Riding periods, 6-Cool down periods)

RIDE: Ride machine for 10 minutes. Make sure to vary your RPM range. Ride machine at 50% of your normal riding pace. Be careful not to put any unnecessary strain on the motor during break-in. COOL DOWN: After 10 minutes of riding, shut machine off and let machine cool down for a minimum of 30 minutes. RIDE: Repeat initial riding period. But ride for 10 minutes at 60% of your normal pace. COOL DOWN: Shut machine off and let machine cool down for a minimum of 30 minutes. RIDE: Repeat initial riding period. But ride for 10 minutes at 70% of your normal pace. COOL DOWN: Shut machine off and let machine cool down for a minimum of 30 minutes. RIDE: Repeat initial riding period. But ride for 10 minutes at 80% of your normal pace. COOL DOWN: Shut machine off and let machine cool down for a minimum of 30 minutes. RIDE: Repeat initial riding period. But ride for 10 minutes at 90% of your normal pace. COOL DOWN: Shut machine off and let machine cool down for a minimum of 30 minutes. RIDE: Repeat initial riding period. But ride for 10 minutes at 100% of your normal pace. COOL DOWN: Shut machine off and let machine cool down for a minimum of 30 minutes.

Break-in should now be complete. Confirm that carburetion settings are correct and give your machine a complete safety check before continuing your riding.

TIPS FOR A SMOOTHER BREAK-IN

- Do not use paddle tires. Stay away from deep sand dunes, mud etc. Until break-in is complete.

- Check that all fluid levels are correct.

- Check carburetion jetting periodically during break-in.

- Check all engine mount and chassis bolts are secure during coold down periods.

- Check all oil or coolant lines are secure and free from oil leaks.

- Make sure exhaust system remains secure. Snug at cylinder head with engine warm.

- Valve clearance should be checked after approximately 5 hours of initial running time.

- Re-adjust cam chain tension when applicable.

- Keep drive chain in adjustment.

 

hey garymanilow

thanx for all that input cuz i get my 465 kit back in about 30 days and i have been loooking for the best break in there is. i think i have found it bro. thanx man

 

when my friend bought his 400ex the dealer told him to ride it under 30mph for 10hrs. and after the first 10hrs change his oil becuase there might be extra metal shavings that came off the engine while breaking it in.

 

Hey fellow rider, I just recently purchased my 3rd 400 ex this past spring and I have broke them all in differently. Pending on your future plans for the machine you can go about this in a few ways. My MX 400 I went right out the enclosed trailer doors and hit my uncles double out back. On my trail 400 for me and my fiance I did just as you planned on doing I rode around the yard and up the street for several days everynow and again just jolting it up in the revs. My 3rd 400 recently purchased I did not shreddddddd like a mad man but I did get up on it right off the bat. I have been a Red Rider for 10 yrs and a 400ex maniac since 99 and I have went about the process several ways and have had no problems with any of them....... IT'S YOUR CALL MAN GOOD LUCK SHREDDDIN WITH THE RED!!!

 

RadChad no problem, glad I could help.Where do you ride in IL? Hey RedRocket, did you see last weeks SouthPark....ahaha......