After lots of help from those on this forum, friends, and a good dealer, I am purchasing a 400ex tomorrow morning. I have some questions about the break-in procedure. What is the procedure, I'm sure it will be as cautious as the other manufactures suggesting not using more than half throttle and other conservatism. A group of friends will be heading up to the Poconos and to keep up on the trails I will need more than half throttle. Will riding it slightly aggresive the first day out do permanent damage, should I consider riding it wimpy around a field by myself for a few hours first. How long should I be cautious with the engine. Will a few all out drag races hurt it. I know the procedure, kind of like not going over 60 mph in a new car (ha!).

On another subject, I am looking to protect my underside and myself. Who makes the best skidplates for the 400ex? I like PRM's stuff but the operation seems a little hokey, what about DG? Also, DG nurf bars look like the might offer a rider a bit more error protection (like your foot slipping off the peg).. is that so? One more question, does the 400ex come with alloy wheels? Thanks, I can't wait!

 

Zjnut.
The break in is pretty simple.The only thing Honda is concerned about is, No Sustained high RPM riding until it's broken in.

Just ride normaly,After the first tank of gas change the oil and the filter(do not put filter in backwards it will stop oil flow)Honda recomends replacing washer on remote oil tank drain bolt with every change.But I do it every third time and it,s fine.After six tanks your broken in.

Check adjustment of throttle slide in carb.Some 2000 models were mis-adjusted.It's right behind the rubber boot that attches to the carb.When you put the throttle to the bar the slide should go all the way up.

Buy chain lube,air Filter oil, fix a flat.And cam straps to tie it down.

As for the skid plate,Watch those pocono rocks. The stocker is ok but aftermarket skids are much better.I have a DG baja it's much better,But I'm still looking for somthing even tougher than that.
Oppions go either way on the nerfs.I just file the teeth to a good edge on my pegs for good grip.

And yes the wheels are a tough alluminum.
Have a good ride!

 

I also am days away from buying the acclaimed 400ex? I am not very mechanically inclined but I plan to adapt to my new quad and develop some skills. Will someone explain the entire procedure, checking and adjusting, to the not so mechanically inclined about the 2000 throttle probs?

Thanks

 

A few weeks ago I asked the same question. I believe it was in Honda section. It was titled Amazingly stupid 400ex carb question. Yoy can get the info there. I was told by my dealer to run it like you want it to run. Just change the oil.

 

I found it thank you. I can't wait to ride it. By the way how often do they recommend you change the oil? And is an aftermarket air filter something i should go ahead and install?

Jeaner

 

hakmazter, who at the dealership told you to run it like you want it to run, They must want you back buying more parts soon.

To break in any new or rebuilt quad, you have to progress in some steps, thats why its called BREAKING IN. If you were to just run it like you want it to run, would there be a phrase, word, or meaning to breaking a motor in? I think not!

To properly break in a motor, first fill the gas tank all the way so you know how much you have run it later. Then when you get the quad home, start it, DO NOT RIDE IT, and let the cyliner warm up to running temp, then shut it off and let it cool down. Do the same thing a few more times, only difference being run it for 5 minutes the second time and then add another 5 minutes of running time for each progressive start. Do this, while occasionally blipping the throttle, a five or six times so you end up running it for about 20 minutes the last time.

This may sound and be tedious, but remember every piece of metal in that motor is brand new so adding heat without load is very important. The idea is to get the piston hard enough to handle the load of riding it. Each time it is heated and cooled, the piston gets harder, it is very soft when new. When the warm ups are done, then you can begin riding it. The idea when you first ride it is to avoid high revs, yet don't let it bog so it doesn't load, up which can do damage also.

For the first ride, just ride at mid throttle for 5-10 minutes then shut it off and let the motor cool down. Then ride it at mid throttle , with occational blips of the throttle (blip=gradually give it more gas and let it rev a little and gradually let off the throttle), for 25-30 minutes and shut it of. Now ride it for about an hour the same way, but you can begin shifting through the gears and speed up and down more, but don't open it up all the way. After that, you should be able to ride it even harder and rev it all the way out on occation.

After at least a tank of gas is used, you can ride it how you like. As TRX430ex stated a brand new motor should have a few more tanks of gas run through it before its ridden at warp speed. Have fun!

If you want the motor to last as long as possible, always let it get to operating temperature before you put it in gear. Yes even if its a 4-stroke, and even after its broke in, and even if its a year old, etc... Also keep the oil changed and air filter clean.

[This message has been edited by Sickman (edited 10-31-1999).]

 

Sickman-
Don't you think your being a tad conservative? Myself being the owner of many different honda products,And to be the only one I know of to have just smoked a ex motor. Through no falt of my own.And backed up by dealer and Honda rep.Hey,, Somtimes things just fail.

Out of all of my Honda products,This is the only one that failed.When I picked up my Honda powered air compresser.The dealer filled it with gas and oil,Gave it one pull and it went straight to full throdle for five minutes.(That's gota hurt)but that compresser is ten years old now,All original and still starts on the first pull.

Say what you will,But as far as I'm concerned Honda's are bullet proof from the start.

My confidence in my now rebuilt 400ex,A little shaken.But I think it's all in my head.

Let us hope that crank journal is as strong as their telling me.I love that bottom end torque.

 

TRX430ex,

Yes that's a little conservative for an air cooled 4-stroke, but a liquid cooled 2-stroke should be broken in thet way. Ask any reputable engine builder. I to have owned basically every sport Honda made, TRX125, 250X, 300EX, & now a 250R made to a 330, and I can vouch for their reliability, but I like to be safe than sorry, so I make darn sure my motors are broke-in. I have had 1 motor to blow up, wana no why, I didn't quite get the piston hard enough to handle being ridden(I never started it and let it cool enough times).

I never used to really warm up my 4-strokes much either, but my boss who raced quads, both 2&4-strokes, and now sprint cars told me that even a 4-stroke should be totally warmed-up before they are ridden. No I never blew one up, but he said that they will last longer. When the engine is first started the exhaust side is much hotter than the intake, and if load is applied too soon, the piston is actually forced against the cylinder wall, not good.

If you or somebody wants to take my advice, good, if not, fine. Like I said, I explained the absolute best, know for darn sure its broke in method. No a 4-stroke is not quite that touchy. But again I like to play it safe, because I can't afford to redo a mistake, college kinda kills my spending ability.

Hondas are excellent motors, but any motor will fail sooner if not properly maintained. Also through my studies as a Mechanical Engineer, I have learned why and how metals react the way they do. I also talk to a lot of people and every one has told me basically the same break-in procedure, local mechanics, Last Rebel Racing, Curtis Sparks Racing, Mumms the Word Racing, EP Racing, and Pro National Racers and their mechanics.

By the way TRX430ex, your crank should be fine, because honda does know what they are doing. Heck if a stock 250R crank can handle my 330, a stock 400EX's crank should hold up.

 

Thanks for restoring my confidence sickman.Coming from a whole family of Engineers,(Who can't tell a joke to save there life.) And being the only black sheep not to have a Dr or masters degree in the lot.

That post reminds me of what my family says.
(If you wern't such a smart a$$ you be working for boeing by now!!)

Good luck on that 330.I'm looking into EFI with a stroker kit.

See yea.

 

One word of advice on warming up 4 strokes. Remember that long periods of idling can limit the amount of oil flow getting up into your head and lubing the cam lobes. While I do allow for some warm-up on my 400cc Wicked Warrior and its high lift cam, I also do raise the throttle to a fast idle as that little impeller Yamaha calls an oil pump doesn't put out all that much flow.

Can't wait for my first run-in, race, and shoot-out with a 400ex. From what I've seen though, it should be a close match up. No chew-em up and eat my dust here, but a proper spanking should put 400ex ego's in their place.

Oh my, a yamaha voice in a honda forum? I must be lost,....... 8-)P

Heapster
400cc Wicked Warrior.