416 break in questions

[jasonwayne222]

What is a recommended break in cycle as far as RPMs go.
I have 11:1pis,stage2cam, and I have a jet kit.
Should I jet it before I break it in or after.
I also ported and polished the head. installed new valves,a heavy duty cam chain, and a slipon exhaust

any recommendations please!

[jasonwayne222]

also what kind of power do you guys think i will make? runnin on 93 octane

[dariusld]

Why port and polish and then just have a slip-on?

[matt14c]

http://www.exriders.com/vbb/showthread.php?s=&threadid=221866&highlight=break

I just followed the second one by Flyin#5 and so far so good. I topped out on compression when I had run about 2-3/4 or so tanks of gas. If you follow the link below for jetting you can do it as you break it in. Make sure you only use petro oil and not a synthetic or a blend. I changed my oil for the first time right around the first tank of gas and adjusted my valves and made sure everything else was still good and tight. Then I changed the oil again when the process was finished around three tanks of gas. I have about 5 tanks of gas through it now and everything seems to top shape.


http://www.jetsrus.com/main_page.htm

[Bill Martin]

Originally posted by jasonwayne222
What is a recommended break in cycle as far as RPMs go.
I have 11:1pis,stage2cam, and I have a jet kit.
Should I jet it before I break it in or after.
I also ported and polished the head. installed new valves,a heavy duty cam chain, and a slipon exhaust

any recommendations please!

You want to run it through a few heat cycles before you start putting any stress on it.
Ride it fairly easy for about ten minuets and then let it cool off.
Do this at least ten times and you can increase the time you run it and how hard you ride it as you go.
The first few heat cycles go easy then you can get on it pretty hard just dont hold it there long and get back off the gas.

I've been told that some manufactures don't heat treat there pistons so you have to do it.
Check your valve clearance after the first or second tank and you should be good to go.
It will take a few tanks to feel the full benefit of your build.
The cool thing about that is you feel the thing getting stringer as you ride it.

It took mine about 6-8 hours ride time for the full effect to be fully realized.
You can do the head pipe later as you go. You wont get the full benefit without the pipe and carb but you will be amazed at the difference.
You can bolt on a pipe your self later when you can afford it.

I have a full race season on mine and I have dogged the sh@t out of it and she has run perfect.
I can hit the starter and it starts instantly no mater how long it sits there. And that’s without a choke on it.

Good luck!!

[jasonwayne222]

ok but i know about heat cycle and all that but can you be more specific like, 1/4 throttle few minutes then 1/2 few minutes. and let cool then slowly up the throttle when u do it a few times.

also i heard not to just let it idle, now the piston has already had 10 hours on it. then only reason i am rebuilding is because i forgot the cam stays and the cam bearings walked off. so im reringin it and addin the stage 2 cam, jet kit, and i port and polished the head because i had time at work so why not. oh and when the bearings slipped off it caused the valves to open incorrectly and contacted the piston, well i smothed out the burrs on the piston and ordered new valves.

so since the piston has already been broken in i think all i really am doin is seatin the new rings

[bigdady536]

Run your quad no more than 75% of it's power for the first 4 hours of riding. Make sure to hit different speeds though dont just ride doing a consistent speed. After 4 hours ride no more that 90% for another 6 hours. Now your break in is complete. After you have reach the end of your break in which is a total of 10 hours make sure to replace the oil and filter as there will be some very small particles of metal. Following this guide is the best course of action to attain the best performance from your upgrades without possibly damaging internal parts.

[Bill Martin]

That’s ok if you want to be that conservative on your break in you can but since you already have seasoned the piston then you can skip that part and just break in the rings.

You can hit full throttle after about a tank of fuel.
When you go through the gears you can hit full throttle for about five seconds then let off. Don’t hold it there, in other words dont rev it out you want to short shift it a little bit.
In other words shift suner then you need to.

After the second tank you can hit full throttle a little longer say 10-15 seconds. As long as you warm it up first.

After the third tank you are good to go. Ride it like you normaly do.

I got on mine pretty hard pretty fast and have had no problems at all.
In fact the guy that built it serviced it a few weeks ago and he told me my rings and cylinder all looked brand new even after a whole season of hard racing down here in the heat of Texas.

Hope that helps.

I don't mean to pickey dut you should never go ten hours with out an oil change.
Oil is cheep motors are not.
When I race I change the oil after every race weekend. Thats about three hours ridding max.If you change it that often then you only need to change the filter every second oil change.
I guess thats why my motor still looks new!!!!!

[jasonwayne222]

ok thanks that all sounds good, im just waiting for the parts to finish comin in.

oh and will my combination of parts be able to handle racing fuel.
I dont plan on running it, but im curious

[honda400ex2003]

this is how i did it. i love break in stuff. http://www.mototuneusa.com/break_in_secrets.htm

my motor runs as good today as it did 2 years ago when i rebuilt it. it has about 2000 miles on the rebuild now
steve

[riotact]

Originally posted by jasonwayne222
ok thanks that all sounds good, im just waiting for the parts to finish comin in.

oh and will my combination of parts be able to handle racing fuel.
I dont plan on running it, but im curious

You will be good to go running race fuel.I have a bone stock 01 400ex and every once in a while I run a tank of Turbo Blue 110 octane through it.For me it's a waste of money but it sure does smell good :cool:

[mcgrath]

Fire it up . Let it warm up. Drive it like you plan on driving it. Break it in like an old lady, It will run like an old lady. Ive been breaking motors in like this for years and have never had a problem. Do you ever wonder why you have 2 identical machines and 1 is a dog and 1 is that super strong machine everybody wishes they got from the dealer? Its not a wonder machine, its broken in properly. Everybody thinks you have to go real easy cause thats what the dealer or manual says. Every other mod you do, the manufacturer wouldn't approve of, but you do what works right?

[Bill Martin]

I've herd that to ride it like your going to ride it. And that’s true to a point. But I still wouldn’t rap it out to soon or to long for a few tanks of gas.
Just short shift it for a few tanks.

As for the race gas you can run it but there is good and bad with that.
With 11-1 it will help some but not a big gain for the money.
Your bike is air cooled so if you go to high on the octane you will fry the piston or over heat the motor.
Remember high octane only works for high compression motors and intended to stop the pre detonation of your fuel.
In other words if you have a high compression and try to run regular fuel it will detonate to soon in the combustion chamber and cause you to loose HP.

Now on the other hand if you have a low compression motor and you put in high octane fuel it will burn to hot and will cause you to loose power do to the higher heat.

Mine is at 12-1 and I run VP U4.2 witch is 102 octane but it also oxygenated so it doesn’t need as much air coming from the carb.
The U4.2 is a direct pure in with no mixing and doesn’t gum up your carb as bad.
If you use race fuel you can leave it in the tank but you want to turn off the petcock and let it run till it runs out of gas.
If you ride more than once a week you don't need to drain the fuel.

I ran strait U4.2 all season this year and had no problems other than the $300. I’m out for the fuel.
So in stead of using race fuel and getting a 2 HP gain as long as the fuel holds out.
I’m going to put that money in a 450 carb and still get the 2 HP gain and don’t have to buy the high dollar fuel.
Hell I may even do both 2 HP from the fuel and 2 HP from the carb = 4 HP.

The only real difference I see with racing fuel is in the throttle response, it’s a little snappier.

Here is VP’s specs on U4.2
U4.2TM
The latest generation of our U4 based fuels; this fuel is a direct pour-in replacement for pump gas, with little to no jetting changes required - +2 main jets and +2 pilot jets at the most. Makes power equivalent to U4 with no sticky residue and a less pungent odor. Designed for stock and modified 2-stroke and 4-stroke applications. U4.2 passes AMA amateur fuel rules and is perfect for club level racing, CCS, WERA and AFM. U4.2 makes up to 6% more power than pump gas.

• Color: Blue
• Oxygenated: Yes
• Motor Octane 102
• Specific Gravity: .784 at 60° F

I hope that helps.

[jasonwayne222]

ok so i put my new valves in today, i lapped the valves and the valve seats and when i filled the head up with fuel, it slowly seeps past the valves,
how bad will this affect the performance. will it loose a little power but not much. its a real slow seep.
maybe put it together and sell it?
or should i bring it to a machinist and have a valve job done to fix it right.

[honda400ex2003]

i would have taken it in first. lol. but i guess you could take it in now if you wanted, i dont think it will make a huge difference but you can never be too sure. if anything make sure it is right before putting it back together if you sell it or not. that would be a bad joke to play on someone. steve

[jasonwayne222]

ya well i only lapped them in for a few seconds each. but i was told by a couple of different people that it could take up to 10 minutes of lapping for one valve to get them lapped in right and to seal correctly, so im gonna keep lapping before i pay a big machine shop bill.

[honda400ex2003]

agreed i would try to do it some more then definitely. you should have said that before and we could have helped you out a bit. it takes quite a while to get them perfect so keep trying. then you will have a job well done and be happy with doing it yourself. steve

[TRXRacer1]

Originally posted by honda400ex2003
this is how i did it. i love break in stuff. http://www.mototuneusa.com/break_in_secrets.htm

my motor runs as good today as it did 2 years ago when i rebuilt it. it has about 2000 miles on the rebuild now
steve
X2

Being careful for a few tanks of fuel is just plain...... :huh