Kawasaki Ninja EX250 break in?

Question

I just bought a new ninja 250, and on the rpm guage, it says to keep the engine under 4000rpm during the "500mile" break-in period. But in order to reach 25mph with staying under 4000rpm, i have to go into the 5th or 6th gear. Do I really have to stay under 4000rpm for the first 500 miles?? Please explain...

Thank you.

Answer 1

i have had two of the 250s, choke is higher than 4000rpm, i asked the dealer about it, they told me not to worry about it too much, my first one i broke in just like i would ride it, and had no problems, my wife's new bike has 100 miles on it , and she'll have to go 7000 rpm to get anywhere.

Answer 2

For the Ninja 250R, if you want to go over 40mph, you will have to go into 5th or 6th gear anyway. This is the only thing I don't like about this bike. You have to shift up fast from first through fourth to be able to go with the flow of traffic.

4000 rpm is a ridiculously low rpm for a break in period. There is no way you can go out and keep the engine at or below 4k rpm when driving in the street with a 250cc engine. You will have a bunch of drivers cursing at you and some others blowing the horns.

I bought my Ninja 250R with 380 miles on it. I rode it in parking lots for long hours until I reached 500 miles. Last night I got on the highway for the first time, reaching 80 mph. The revs were up in the 9 - 10k rpms. I don't think I redlined it though. I was so excited that I was finally able to ride my bike at regular speed, I forgot to look at the sticker on the tachometer again. It reads something like: " for better engine performance...keep revs at or below 4000 rpm from 0 to 500 miles AND under 6000 rpm from 500 to 1000 miles". If I respect this second break in period, I will have to ride my bike around the block for a year at 25 mph.

I hear Kawasakis are known for taking abuse...I know mine is one even though I try to take good care of it. I believe it's better to put the bike in short cycles of 7k and 8k rpm, let it cool down and repeat it periodically than staying under 4000 or 6000 rpms for 500 miles every time you ride it. My bike only has 620 miles on it. Just before hitting 1000 miles, I will rev it up again for a short time at 9k rpm, change the oil and filter and I know this baby's engine will last a long time...

Answer 3

No offense to anyone, but by all means don't redline a new engine or newly overhauled engine to "get it used" to high rpms. That's mighty dangerous advice. And the old adage about "fast break in, fast bike" is also a bunch of hooey. Not only have I worked on engines all my life, but I also happen to know why and how things work, including the process of breaking in a new engine.

You need to keep in mind that there's a lot of rough surfaces inside your new engine including cam lobes, valve buckets and shims, cylinder walls, piston skirts, wrist pin bearing surface and crankshaft and cam bearings. The cam lobes might look nice and shiny to the naked eye, but look at it under a microscope and it'll look like the surface of the moon. Look at the cylinder and you can visually see hone marks and it'll actually feel rough to the touch. The purpose behind "breaking in" an engine is to give all those rough surfaces a chance to get to know each other under friendly cirmcustances and in the process they'll polish each other up. Bear in mind the only thing keeping your engine from self destructing is a tiny film of oil between the moving parts. The tips of the microscopic "mountains" on two freshly machines surfaces will cut through the oil film slightly and gradually wear down the rough surfaces on each other, much like a rock tumbler does. Once polished up, the oil film will then keep them from actually physically touching each other. Lugging an engine at low engine speeds, high rpm's or full throttle for extended periods puts high loads on bearings and piston skirts. If the surfaces haven't polished up adequately, the rough surfaces will cut through that thin oil film and rather than gently knocking the rough edges off each other, they'll grind into each other metal to metal. If you want scored pistons skirts slapping for the rest of your motorcycle's life, consider the break in period BS and red line it as suggested. Do the same if you want to scuff the piston pin bearings and that way you'll have the pleasure of listening to that ticking noise located high in the engine for a long time. You'll also be able to listen to that knocking noise down deep for the rest of your days or until the engine locks up, which ever comes first.

I don't want to alarm you unduly and it's fortunate most motorcycle engines are over engineered, probably specifically for those characters who redline it right off the showroom floor. It's truely amazing those engines hold up as well as they do under the heavy hand of their unknowing or uncaring owners. Whoever said ignorance is bliss never successfully broke in an engine I bet. As was mentioned, vary the engine speed the first several hundred miles and don't drone across the entire state of Kansas at a steady 60 mph. Personally I think 4,000 rpm is rather conservative and 6,000 would probably be more in line as long as you aren't twisting the throttle wide open when you do it. However, don't baby the engine TOO much. Every so often in the first 500 miles, momentarily open the throttle up, maybe 3/4 open. What this does is increase the combustion pressures ins the cylinder which puts more load on the piston rings and forces them tighter against the cylinder wall, eventually giving the cylinder wall a mirror finish. If you don't, the rings will take forever or will never really seat well. The result will be reduced horsepower and more blow by past the rings into the crankcase. My old Kawasaki was supposed to had the oil changed at 500 miles and I don't know if thosse recommendations have changed any. By all means, do change the oil and filter at the recommended mileage. You don't want all those metal particles that were knocked off circulating back through the bearings. Just remember whether it's booze, women or motorcycles, practicing a little moderation makes for a much longer, happier life.

Answer 4

Don't keep the RPMs at a constant rate.
Vary the engine speed.
Right in the middle of 4,000 RPMs and red line should be the fastest the engine spins, no faster.
But don't rev it to that point every chance you get.
Take it easy, but don't be afraid to rev the engine when you need it.
Break-in this way will be fine.

Answer 5

Do whatever the owners manual for your motorcycle says to do for proper break in. Yes it is necessary for you to keep rpm's low for break-in. The rings need time to properly seat to the cylinder for long life performance. The rings will not seat properly if ran at high rpm's thus shortening the life of the engine. As I stated before, just follow the recommendations that are set for in your owners manual for proper break-in.

Answer 6

HAHAHA!!! you bought a ninja 250r?, ignore the sticker, just red line the bike, the break in is BS to break it in you have to red line it alot of time to get the engine used to high revs, ignore the break in dude, when I got my fz6 I didnt do the break in rules and its fine

Answer 7

Since you didn't listen to the advice before.... I would suspect that the bike has more mileage than is shown and that their Gurantees won't be in writting. Let the buyer be ware.