Trouble with starting speed

[vmlp]

Hello All,

I brought 2007 - Ninja EX250 couple of months ago, Recently My bike is somehow not picking-up the speed! The First 3 gears is now feels like very slow & the RPM raves to >6K. Week ago, This wasn't a problem! The bike has 3600 miles on it, Oil change done regularly and Last weekends, I did check carburetor and confirmed it is cleaned like new, The spark-plugs were replaced with NGK -CR8HSA with correct gap-- But no deference so far!!!!
I need help here....Does anybody had this problem? Please help.
The only thing comes to my mind is valve clearance - exhaust valve clearance was little tight (0.10mm, the range is like .08 to .13mm if I am not wrong).

Please help.

[Alex]

If it won't rev past 6k, and it feel terribly underpowered, I wonder if it is even running on both cylinders.

/moved to pre-gen tech area

[alex.s]

definitely sounds like 1 cylinder. maybe one of the coils? maybe something simple like one of the coil wires came unplugged. i did that the other day lol. but then again i dont think it would really idle if it was only running on 1 cylinder without gas

[vmlp]

Originally Posted by alex.s

definitely sounds like 1 cylinder. maybe one of the coils? maybe something simple like one of the coil wires came unplugged. i did that the other day lol. but then again i dont think it would really idle if it was only running on 1 cylinder without gas

Thanks Alex/Alex. S
I did checked the coil connections are OK on both sides.
The bike can rave up > 6K or >7K but the speed won't change!!! It just raves up but speed does not change with raves.
Air filter or air leaking would cause such a problem?

Thanks,

[alex.s]

oh... clutch?

[DevinWolfe]

Originally Posted by alex.s

definitely sounds like 1 cylinder. maybe one of the coils? maybe something simple like one of the coil wires came unplugged. i did that the other day lol. but then again i dont think it would really idle if it was only running on 1 cylinder without gas

My new gen idled and ran very rough on only 1 cylinder (carb diconnected from that cylinder) but it did run and pull away from a stop very slowly.

Have you tried disconnecting one plug wire at a time to see if the idle changes? If it does not change on one side or the other your problem is on that side.

[vmlp]

Originally Posted by DevinWolfe

My new gen idled and ran very rough on only 1 cylinder (carb diconnected from that cylinder) but it did run and pull away from a stop very slowly.

Have you tried disconnecting one plug wire at a time to see if the idle changes? If it does not change on one side or the other your problem is on that side.

Thanks DevinWolfe!/Alex S.
I will try these 2 suggestions...tomorrow morning or tonight if possible.
I'll keep you guys posted with the updates...
Thanks again

[alex.s]

i'm still confused on exactly the problem. you say in first gear, with the clutch lever all the way out, you give it gas and it revs up higher like to 6 or 7K, but you arent moving?

[vmlp]

Originally Posted by alex.s

i'm still confused on exactly the problem. you say in first gear, with the clutch lever all the way out, you give it gas and it revs up higher like to 6 or 7K, but you arent moving?

Hi Alex S.
OK, The speed on 2nd & 3rd GEAR not changing while you revs up high and clutch is fully released (all the way out)!!! This is happening since last week... It was moving OK with good pick-up and the speed used to varies according to the engine revs.

Thanks again,

[DaBlue1]

What did you do different between the time the bike was running fine to now?
Do you have the proper slack on your clutch lever?
What kind of oil did you use and how much?
Does the tranny make any wierd noises?
Is there positive engagement of the gears (do they click in)?
Is your shift technique proper? When you hit neutral, do you release the shifter momentarily or keep shifting up?

If the engine revs and the speed is not changing thru two gears, your clutch is either not engaging fully (maladjusted/slipping) or you have some internal tranny problems or hitting false neutrals.

[alex.s]

i mean its definitely a slipping clutch. like blue said check your clutch lever cable slack. what kind of oil did you put in it? if you didn't put something wonky in just change your clutch plates

[vmlp]

Originally Posted by DaBlue1

What did you do different between the time the bike was running fine to now?
Do you have the proper slack on your clutch lever?not sure
What kind of oil did you use and how much?-Castrol 4 stroke motorcycle oil- 1.9 liters
Does the tranny make any wierd noises?Didn't noticed!
Is there positive engagement of the gears (do they click in)?sometimes yes
Is your shift technique proper? When you hit neutral, do you release the shifter momentarily or keep shifting up? mostly i keep shifting up!

If the engine revs and the speed is not changing thru two gears, your clutch is either not engaging fully (maladjusted/slipping) or you have some internal tranny problems or hitting false neutrals.

Thanks DaBlue1, Alex S.
I just did 1 oil change with Castrol 4 stroke motorcycle oil - 1.9 liters. It was working fine since than til last week!
I've posted my answers in red above.
I was sick today and could do anything...I still need to check coils, spark plugs and clutch.
Thanks again,
V

[DaBlue1]

I'd start with checking to make sure your clutch is properly adjusted and then make sure your shifts are crisp and that you are not getting false neutrals.

[vmlp]

Originally Posted by DaBlue1

I'd start with checking to make sure your clutch is properly adjusted and then make sure your shifts are crisp and that you are not getting false neutrals.

Thanks DaBlue1, Alex S.
Your suggestion worked!
Thanks all of you who responded - It was a great help.

Thank you all.