I just got this 2006 Ninja 250, so far it only have less than 250 miles on it, I only rode for about 100 miles after the purchase, and this is my first motorcycle. One thing I notice recently is that I can accelerate the bike to 40 mph no problem around the 3-4 gear.

But going from 40mph to 50 is very very hard. Even after I twist the throttle all the way in around the 4th gear, the RPM still goes up very slowly from 6-8, I sometimes have to downshift 1 gears for the RPM to go up to 7-8, then up shift again, but even with all of this. So far I still have not gone more than 50 mph yet. I'm sure if I will eventually get it up to 60+ mph, but I feel like that is going to take a long time to happen.

I don't even want to think how can I ever go to freeways, it will take so long for me to accelerate to 60, I'll be a road hazard.

I am a new rider, so is this normal for 250? And does it have to do with the fact that the bike's engine is still in the break-in period?

Also another thing I notice but might be unrelated, after the RPM goes to more than 7, the sound the engine makes is a bit different, yes it's louder, but I feel like it's a bit more than that, I can't describe it, but the pitch of the sound is much higher as well as the noise level. So when I hear that I always shift gear, I'm afraid it will damage the engine or something.

Other than ride it, what have you checked?
Have you checked the air filter?
What size sprockets are on the bike?
What condition are the spark plugs in?
At what RPM speed do you normally shift gears? 40-50 mph should be very easy to reach in 3rd or 4th gear.

06 with 2500 miles could be gummed up carbs

Other than ride it, what have you checked?
Have you checked the air filter?
What size sprockets are on the bike?
What condition are the spark plugs in?
At what RPM speed do you normally shift gears? 40-50 mph should be very easy to reach in 3rd or 4th gear.

I have not check air filters, the sprocket are original factory size, I have check the spark plugs, they are good. I normally shift gears at 5-6.

06 with 2500 miles could be gummed up carbs

Sorry, that was a typo, it has less than 250, not 2500 miles on it.

Carbs probably need cleaned. Try shifting at 12k rpm's.

Sorry, that was a typo, it has less than 250, not 2500 miles on it.

even worse.

that means it was ridden average 35 miles a year. this bike has done alot of sitting around. def clean those carbs...

also....ninja 250's arn't that fast anyway :)

Oh the carbs are completely cleaned, when I first got it the engine won't even start without cleaning the carbs.

I'm just curious around RPM do you guys shift? For me, it seems I always shift at around 5-6k RPM which is very easy to get for from 1-40 MPH, but after the 3rd or 4th gear after I shift, the RPM meter stays at 5-6k, and it takes a much longer time to go up to 7-8K as well as speed going up.

But I do get the feeling that I should shift the prior gears at much higher RPM and well as my current gear?

even worse.

that means it was ridden average 35 miles a year. this bike has done alot of sitting around. def clean those carbs...

also....ninja 250's arn't that fast anyway :)

Well, not average of 35 miles a year... more like 100 miles during the first month, and 0 miles for the rest of the 6 years :D

For example, when I'm at 5th gear at around 4-5k RPM, no matter how much gas I give it, the speed won't increase at all.

This is normal right? Because I changed gear too early?

You need to rev a 250. On bigger bikes those speeds+rpms are fine, but the 250 doesn't have anywhere near the power of something larger

Have you checked the air filter?


This is very important.

After 7 years of storage that filter needs oil, ..........if that foam didn't disintegrate itself by now.

If the inbox is free, the next thing to check is any restriction to the supply of fuel.

I shift at around 8k when commuting and somewhere between 9k and 11k when out in the hills

When I had my 250, I don't think I was ever below 5,000 not even when going slow. I'd shift typically around 8,000-9,000.

Make sure the bike is warm before your shifting at these high rpm. Touch the case on the right side. If it is too hot to hold your hand on it then your good to rev it. But stay under 5k when the bike is cold. Take a few warm up laps around the subdivision or something before having to go anywhere. Rotella 15w40 for a cheap good oil and a wix filter. Change it every 2000 miles tops. Its cheap easy and a good thing to do. Oil the airfilter and run ethanol free gas. I got my bike with 250 miles on it too. Carb cleaning and oil change etc later, it runs like a champ.

Thanks, great advice. Maybe just one more question, I find my bike is really slow to warm up, sometimes I need to open the choke partially for up to a few minutes otherwise the engine just shuts off on me. I assume this is because the engine is not hot enough right?

Or is my fuel tank have water inside of it? Because I left the bike at friend's place for 2 days, I found out that his sprinkler system turns on every morning for about 15 minutes and my bike is all wet because of it, I'm just afraid that there might be water drops gather at the top of the fuel tank and leaking inside. So is there anyway to check if you have water in your fuel tank?

Also during the warm up process, the engine won't start with full choke on, unless I give it a bit of gas to start.

What I have to do is that, press the start button, I would hear this put-put-put then it quickly dies out. UNLESS at the same time of starting the put-put-put I give it throttle then immediately the engine would start come online and jumps to about 4-5k RPM (I can let go of throttle and it still runs) it stays there until the engine fully warms up, (this is with choke on btw), but if I ever put off the choke in the process of warming up, the engine would dies right away.

I'm not worried about turning off choke and engine dies during warm up, I heard this is normal.

But is the other part normal? The one that immediate after the engine starts I have to give it gas to make it from dying out (once I give it gas to start, the engine can keep going with no problem).

With everything else being said, the bike runs excellent (I think).

Try putting some seafoam in the gas tank and see if that helps the carbs. If it's warm out you shouldn't really need to use the choke.

You're not going to go anywhere on a 250 Ninja if you don't rev it to where the power is. The older Pre Gen Ninjas need to be near 10,000 to really get rolling. There's not much power or torque available at 5000 or 6000.

Change the oil and filter if you haven't already, check the basic maintenance items, and let 'er rip. Don't hesitate to go to 10,000 or beyond if you need to (once it's at operating temp - as Quarterliter noted).

If you want a 250 that doesn't need to rev to that range you need to look at the CBR250R. The 250 single isn't a screamer like the Ninja's twin.

As long as you do the proper maintenance and use decent oil (and keep track of the oil level), the high revs aren't a problem.

Here's a comparison of 250 power curves. The Ninja curve is the later model than yours, and actually makes its power lower, but you can see why you need to spin pretty high to get to the power.

http://i132.photobucket.com/albums/q28/jverg/Misc/146_11032011-250s-dyno-horsepower_zpsa4db9c80.jpg (http://s132.photobucket.com/user/jverg/media/Misc/146_11032011-250s-dyno-horsepower_zpsa4db9c80.jpg.html)

.... I find my bike is really slow to warm up, sometimes I need to open the choke partially for up to a few minutes otherwise the engine just shuts off on me. I assume this is because the engine is not hot enough right?




....Also during the warm up process, the engine won't start with full choke on, unless I give it a bit of gas to start.

What I have to do is that, press the start button, I would hear this put-put-put then it quickly dies out. UNLESS at the same time of starting the put-put-put I give it throttle then immediately the engine would start come online and jumps to about 4-5k RPM (I can let go of throttle and it still runs) it stays there until the engine fully warms up, (this is with choke on btw), but if I ever put off the choke in the process of warming up, the engine would dies right away.

.

Sounds like your idle speed may be too low. Once the bike is fully warmed, set the idle speed @ 1500 rpms and see how it does. Also add some Star Tron Fuel Treatment (http://mystarbrite.com/startron//content/view/35/47/lang,en/) and some fresh 87 octane gas to your tank.

But going from 40mph to 50 is very very hard. Even after I twist the throttle all the way in around the 4th gear, the RPM still goes up very slowly from 6-8, I sometimes have to downshift 1 gears for the RPM to go up to 7-8, then up shift again, but even with all of this. So far I still have not gone more than 50 mph yet. I'm sure if I will eventually get it up to 60+ mph, but I feel like that is going to take a long time to happen.


I'm not sure that your original question was answered definitively - this is not normal. This sounds nothing like an issue with you not being in the powerband, and everything like poor ignition.

Can you define slowly - how many seconds does it take to accelerate from 40 to 50?

If you're on the flat and go WOT there should be absolutely no need to have to downshift to accelerate - my (admittedly newgen) Ninja had enough pull in top gear to get me from 40 to 50 without requiring a downshift.

As was mentioned you need to check airflow, spark and fueling - any of these can cause a power loss.

As for needing the choke to start, my Ninja always needed the choke, no matter what the ambient temperature was - and I often had to give it gas right away. I would treat these as 2 separate issues and worry about the poor acceleration first - but again, please define "slowly" for us.

I believe that your choke is messed up, I had the same issue but with a boat and it was the choke not opening.Take a look at the choke cable and its operation. If the choke is on at high speed, the motor is getting too much fuel.

I'm not sure that your original question was answered definitively - this is not normal. This sounds nothing like an issue with you not being in the powerband, and everything like poor ignition.

Can you define slowly - how many seconds does it take to accelerate from 40 to 50?

If you're on the flat and go WOT there should be absolutely no need to have to downshift to accelerate - my (admittedly newgen) Ninja had enough pull in top gear to get me from 40 to 50 without requiring a downshift.

As was mentioned you need to check airflow, spark and fueling - any of these can cause a power loss.

As for needing the choke to start, my Ninja always needed the choke, no matter what the ambient temperature was - and I often had to give it gas right away. I would treat these as 2 separate issues and worry about the poor acceleration first - but again, please define "slowly" for us.

I think the slow acceleration is my driving problem, I was at 4th or 5th gear at 4-5k rpm and it won't go fast no matter how much gas I give it, but today, I tried to shift only at near 6-7k RPM and I see some very big improvements. So far I have not yet gone faster than 50 mph yet, and I think if I only shift around 7k rpm it shouldn't be a problem.

What I am more concerned is potential water in my fuel tank, my bike was soaked from my friend's water sprinkler system. Does anyone know if Ninja's fueling port have some kind of seal? Preventing water from leaking inside when it's fully closed?

I believe that your choke is messed up, I had the same issue but with a boat and it was the choke not opening.Take a look at the choke cable and its operation. If the choke is on at high speed, the motor is getting too much fuel.

Would be, when I try to cold start, it will only start with choke all the way on, and I have to give it a bit of gas from engine dying out, and once the engine starts with full choke on, it immediately jumps to 5-6k RPM.

I need to keep this for at least 1 minute, during this 1 minute, any lowering of the choke will kill the engine, but after 1 minutes or a bit more, I can try to lower the choke a bit and it might go down to 4k rpm, but if I'm not carefully, if I accidentally lower the choke too much the engine dies as well.

Sounds like your idle speed may be too low. Once the bike is fully warmed, set the idle speed @ 1500 rpms and see how it does. Also add some Star Tron Fuel Treatment (http://mystarbrite.com/startron//content/view/35/47/lang,en/) and some fresh 87 octane gas to your tank.

Once the bike is fully warmed and in operation, the idle speed is actually just around 1.5k RPM. The bike runs great after 10 minutes or so, it's just the first few minutes gets my all worried every time I start it up.

You're not going to go anywhere on a 250 Ninja if you don't rev it to where the power is. The older Pre Gen Ninjas need to be near 10,000 to really get rolling. There's not much power or torque available at 5000 or 6000.

Change the oil and filter if you haven't already, check the basic maintenance items, and let 'er rip. Don't hesitate to go to 10,000 or beyond if you need to (once it's at operating temp - as Quarterliter noted).

If you want a 250 that doesn't need to rev to that range you need to look at the CBR250R. The 250 single isn't a screamer like the Ninja's twin.

As long as you do the proper maintenance and use decent oil (and keep track of the oil level), the high revs aren't a problem.

Here's a comparison of 250 power curves. The Ninja curve is the later model than yours, and actually makes its power lower, but you can see why you need to spin pretty high to get to the power.

http://i132.photobucket.com/albums/q28/jverg/Misc/146_11032011-250s-dyno-horsepower_zpsa4db9c80.jpg (http://s132.photobucket.com/user/jverg/media/Misc/146_11032011-250s-dyno-horsepower_zpsa4db9c80.jpg.html)

Thanks for the tip, I didn't know that. This is my first motorcycle, when I drove my car I never let the RPM go more than 3k acceleration or starting. Everything was so smooth lol, I'm just afraid that rev the engine too hard will make my Ninja explode, but I know now this is not the case.

When you cleaned your carbs, did you clean the pilot jets as well? A lot of people miss those.

Here is what normal acceleration on an unmodified Ninja 250 is like:

Yd_WRQQxFqk

FYI: If you lean forward, you can avoid accidental wheelies.

.......when I try to cold start, it will only start with choke all the way on, and I have to give it a bit of gas from engine dying out, and once the engine starts with full choke on, it immediately jumps to 5-6k RPM...........

Those high rpm are hurting your cold engine.

Lubricate your choke mechanism and cable to be able to fine adjust the rpms' at start up never higher than 3K.

Please read this:
http://faq.ninja250.org/wiki/What_is_the_correct_way_to_apply_choke_at_startup%3F

What about that neglected poor air filter? :( :( :(

:eek:immediatly jumps to 5-6k

That's what it will do with the choke fully on.

Those high rpm are hurting your cold engine.

Lubricate your choke mechanism and cable to be able to fine adjust the rpms' at start up never higher than 3K.

Please read this:
http://faq.ninja250.org/wiki/What_is_the_correct_way_to_apply_choke_at_startup%3F

What about that neglected poor air filter? :( :( :(

Thanks, that's good advice, I'll check air filer as well as choke line.

I'll try the best method to perfecting my warm up process. I got to say, motorcycles requires A LOT more hands on attention than my SUV lol. So is all carbrated bike like this? Are fuel injection bikes like CBR250 don't need to warm up?

Are fuel injection bikes like CBR250 don't need to warm up?
They don't need any input from the rider during warm-up. The F.I. system reads the engine temp, air temp, etc and enrichens the mixture just enough to maintain a slightly high idle for only as long as necessary.

The choke isn't that big of a deal. Once you get it figured out you won't think about it.

The choke control is touchy, but you can get it to idle at 3K RPM with a little practice.

Nevertheless, it still sounds like your carbs aren't right.

The carb has been stripped and clean to the very last detail, includes the jets.

I may have figure out the problem, when I open the seat cover, I can see 3 rubber tube supplying oxygen going to the crab (I think), one of the tube is bend in the middle, for example, have you ever tried to wash your car at your own drive way, then suddenly the water flow stops or became very slow, then you figure out that the hose rubber tube is twisted onto it self and water flow became a problem. It is exactly like that for one rubber line, and there is no way to straighten it, because I think it has been bend for so long, the rubber has became fatigue and permanently bend out of shape.

There are two very good points that have been previously mentioned, and until you check them, you are not going to be able to diagnose the problem correctly.

1. Is your Air Filter clean?

2. Did you clean the pilot jet when you cleaned the carbs?

- These are hard to get to and pretty much invisible when installed.

Edit, you replied as i was typing this message :)

The carb has been stripped and clean to the very last detail, includes the jets.

I may have figure out the problem, when I open the seat cover, I can see 3 rubber tube supplying oxygen going to the crab (I think), one of the tube is bend in the middle, for example, have you ever tried to wash your car at your own drive way, then suddenly the water flow stops or became very slow, then you figure out that the hose rubber tube is twisted onto it self and water flow became a problem. It is exactly like that for one rubber line, and there is no way to straighten it, because I think it has been bend for so long, the rubber has became fatigue and permanently bend out of shape.

Which hose is it? Can you take a picture?

.... I can see 3 rubber tube supplying oxygen going to the crab (I think), one of the tube is bend in the middle,

You may be referring to CA. Emission hoses on the tank. Instead of venting the tank directly to the air, gas fumes are contained in a closed system (if it's still installed on the bike.)

http://faq.ninja250.org/images/thumb/c/c2/161779203-S.jpg/300px-161779203-S.jpg

The middle hose is just a vent hose and connects to nothing. The hoses on the left and right connect to a canister.

You may be referring to CA. Emission hoses on the tank. Instead of venting the tank directly to the air, gas fumes are contained in a closed system (if it's still installed on the bike.)

http://faq.ninja250.org/images/thumb/c/c2/161779203-S.jpg/300px-161779203-S.jpg

The middle hose is just a vent hose and connects to nothing. The hoses on the left and right connect to a canister.

It is the far right one, the previous owner must have lock it under the seating locking mechanism and put it like that for many years, now the hose is permanently bend somewhere in the middle. Do you know what does that hose connect to?

There are two very good points that have been previously mentioned, and until you check them, you are not going to be able to diagnose the problem correctly.

1. Is your Air Filter clean?

2. Did you clean the pilot jet when you cleaned the carbs?

- These are hard to get to and pretty much invisible when installed.

Edit, you replied as i was typing this message :)

I don't know if the filter is clear or not, I took it out and it looks clean enough, I even use my vacuum machine to vacuum on it a bit as well as use my compressor to blow air on it quite a bit, some dust come off it, but not that much.

Both pilot jet was clogged, they have to use the needle and wire to clean it very carefully, now it's cleaned, before it was not cleaned the bike won't even start at all.

At this point I have to wait until tomorrow to start the bike to see any difference, because I want it to cool down to the air temperature first, I will also see if there is anything I can do to the hose to strengthen it a bit.

This might help a little:

http://faq.ninja250.org/images/thumb/7/7b/Gas_fuel_calif_emiss.jpg/458px-Gas_fuel_calif_emiss.jpg

But it doesn't look like any of this stuff would interfere with the engine that bad. It connects to the overflow line of the carb and another spot connects to the airbox. There is nothing standing out that would actually interfere with the running of the bike that I can see.

Ok, I might have found the problem, when I paid 200 dollars to do a full tune up, the mechanic must have mixed up the tube, right now the far right tube is leading to no where, the middle tube is connected to something. So far I have't had any luck disconnecting the tube yet because they are fit on very tightly, I need to buy a can of WD-40 to see if I can loose it up a bit.

I have cleaned and oil up the air filter, it was not that dirty as far as I can tell. I hope doing this, combined with reconnect the correct tubes can solve the problem.

I also checked the choke adjustment, it was fine, all the range on the choke itself is well represented by the full movement on the choke control under the bike.

I put more sea foam inside the tank and letting it sit overnight.

What tubes are you referring to?

Pulling make them grip harder, try pushing any tube from the end.

....So far I have't had any luck disconnecting the tube yet because they are fit on very tightly,

....I put more sea foam inside the tank and letting it sit overnight.

All you need is a small pair of needle nose pliers and gently work the rubber hose off the metal nipples on the tank.

How much SeaFoam have you used? Seafoam is of no use just sitting on the tank. It needs to be mixed with some fresh gas and allowed to run into the carbs. That means you need to either ride the bike or run the engine until the SeaFoam treated fuel is in the carb bowls. If your concern is water in the tank, pull the fuel line off the carb, put the petcock on prime and drain the old gas into a suitable container and add some fresh gas.

The pregen petcock doesn't have a prime. But I am confused as to why he is removing tubes. If they are stuck, then its likely because they have been that way for a while. I could understand how someone could mistakenly mix up the tubes on the back of a CA tank, but I don't see how any of them could affect the running of the engine.

EDIT: Ok, I do see something that could affect it, but its a long shot. The vent from the carbs goes to a round canister looking thing. If the vent tube (large vinyl tube coming from between the two carbs) is stopped up, the fuel wont flow into the carbs properly. Try disconnecting it from the canister.

EDIT2: Did you ever test the petcock to make sure it isn't leaking? For instructions, see my blog below. Looking at the CA schematic, a leaky petcock would cause the round canister thing to fill with gas as create a liquid lock and thus create a problem filling the bowls and hence your symptoms over 40 mph.

http://faq.ninja250.org/images/thumb/c/c2/161779203-S.jpg/300px-161779203-S.jpg

Tube #3 was at middle position, and Tube #2 was at right position, it got mixed up when the mechanic put it back.

I was able to get the tube off and switch it around by using a lot of WD40 and some tools squeezing/pushing at the end.

I have not had the chance to test petcock yet, so far it is not showing any problems, it is not leaking anything, and when the bike is full up and running it's fine. However last time I did have to push start the bike after warm up, but I suspect this might have to do with the problem of wrong tube connection or bad air filter. I'll do the test that you listed nonetheless.

The petcock tends to leak internally more than externally. Follow the directions on my blog for testing it. It will take you about 10 minutes max.

I would just like to say, you guys ROCK :thumbup:

After finishing cleaning the air filter, apply new oil on it, corrected the tube connection the bike functions great.

Before when I cold start the bike, it was either 0 RPM (no start) or 5k RPM.

Today I was able to actually start the bike without using the choke, and able to adjust the choke and adjust the RPM speed all the way from 2k to 4k at cold start up.

I also notice that the bike makes less noise, smoother acceleration, and most noticeable, much much smoother engine breaking/down shift gear. Before when I was down shifting gear no matter how low the RPM was, I always feel a jolt as gear shifts, now I still feel slight jolt but much much smaller in force.

I can't believe how nice this community is, thanks everyone who have posted in this trend and give me advice. :thumbup:

I would just like to say, you guys ROCK :thumbup:

After finishing cleaning the air filter, apply new oil on it, corrected the tube connection the bike functions great.

Before when I cold start the bike, it was either 0 RPM (no start) or 5k RPM.

Today I was able to actually start the bike without using the choke, and able to adjust the choke and adjust the RPM speed all the way from 2k to 4k at cold start up.

I also notice that the bike makes less noise, smoother acceleration, and most noticeable, much much smoother engine breaking/down shift gear. Before when I was down shifting gear no matter how low the RPM was, I always feel a jolt as gear shifts, now I still feel slight jolt but much much smaller in force.

I can't believe how nice this community is, thanks everyone who have posted in this trend and give me advice. :thumbup:

You are welcome :)

You should work on the bike yourself, that way you know exactly what you did. I am certain you won't cut corners when it comes to your own vehicle.

For future reference, when you try to take a rubber tube that is seized on a nipple, try twisting it in place to break the bond over long periods of sitting.