Acceleration issues from a stop

[edxmon]

Hi guys,

I got a used '08 about 3 weeks ago. I've been riding it around the block since then every other day. I've cleaned and lubed the chain and also changed the oil and oil filter. The bike does take a while to warm up even after I adjusted the idle speed to around 1500rpm (was idling at ~900-1000 before). The problem I keep noticing because it's very annoying, is that from a dead stop (stop signs, yields, or turns around my block) the bike looses power if I accelerate even a bit suddenly. Example, I'm taking off from a stop, I give it enough gas to take off, it begins moving, so I continue to roll on the throttle to accelerate the bike responds 2-3 seconds later. For those 2-3 seconds I'm feeling like an idiot because I'm only barely rolling along sometimes it even feels feels like the bike is going to die.

I have to admit I'm just learning to ride, so I'm not 100% used to the clutch, so I might be releasing the clutch too suddenly and giving too little gas. Although my worries are something backed up by trying to give it throttle while it's just sitting in neutral idling. If it's idling and I try to give it a large amount of throttle suddenly the bike dies. If I smoothly raise the rpm to 3000+ then gas it suddenly everything is fine and the engine responds immediately.

I just put 1/2 tank of gas with the appropriate amount of seafoam so I'm waiting to run through that before I do any work, and even then I want to wait 'till we have SoCal tech day to get some help from experienced members instead of taking it to a shop I know nothing about.

If you guys have any ideas, or if this is normal for the bike please let me know. Thank in advance guys.

P.S. Bike is completely stock, could this be caused by a super filthy air filter?

EDIT: http://www.ninjette.org/forums/showt...ght=air+filter

A quick search came up with Kkim's shimming thread, and the first thing he mentions are that it solves all of the problem's I've mentioned here, go figure.
If it could be anything else, please post it though guys.

[cbdallas]

You're encountering one of the most common problems with a 250R. They don't like to be spurred until they're warmed up. If you're only riding it around the block, you're likely not getting it very warm, and until it's warm, it's gonna be bitchy about how much throttle you give it in the low RPM range. Take it for a real ride and you'll probably notice that this issue clears up when the engine reaches operating temperature.

[edxmon]

Originally Posted by cbdallas

You're encountering one of the most common problems with a 250R. They don't like to be spurred until they're warmed up. If you're only riding it around the block, you're likely not getting it very warm, and until it's warm, it's gonna be bitchy about how much throttle you give it in the low RPM range. Take it for a real ride and you'll probably notice that this issue clears up when the engine reaches operating temperature.

Well heck, I'll have to adventure out of my comfort zone then!

P.S. is that a 250 in your AV? something looks different about it and I like it!

[csmith12]

If everything is right. With 3-5 minutes of warm up time, it should accept any amount of throttle you want to give it.

Next Steps;

Check/New air filter
Check throttle cable adjustment
Seafoam
Shim/desnorkle at a tech day or in your spare time

Hopefully your good to go after that.

[DaBlue1]

A stock Ninja has very little power in the low rpm range. A good & common rpm to launch the bike is close to 3k and above. Trying to launch the bike just off of idle can be done but as you can tell it's not good in a traffic situation. Launching the bike at a higher rpm speed will require a little more twisting of the throttle, something you may have to get used to as a new rider. One caveat of the CV type carbs is a tiny lag in throttle response when snapping open the throttle. This is normal and is due to the slides in the carbs being vacuum operated as opposed to being mechanically operated by the throttle cable.

Being that you bought the bike used a little preventive maintenance should be in order. One item that is included in that maintenance checklist is the air filter. And yes, a super dirty air filter can cause throttle response problems. It is easy to check and clean or just replace. Shimming of the needles will help a little with throttle response in the low rpm range (about 1/8 throttle) but is most effective in the 1/4-3/4 throttle (midrange).

My suggestion would be to continue practicing riding the bike and getting more familiar with the clutch, throttle and engine operating speeds. Once you are comfortable with that then look at doing intake mods.

[cbdallas]

Originally Posted by edxmon

Well heck, I'll have to adventure out of my comfort zone then!

P.S. is that a 250 in your AV? something looks different about it and I like it!

It's a 650R.

[edxmon]

Originally Posted by csmith12

If everything is right. With 3-5 minutes of warm up time, it should accept any amount of throttle you want to give it.

Next Steps;

Check/New air filter
Check throttle cable adjustment
Seafoam
Shim/desnorkle at a tech day or in your spare time

Hopefully your good to go after that.

I've let the bike "Warm up" for way longer than that, but like I mentioned before I'v only every ridden it around my block/neighborhood for 1-2hrs at a time at max 30mph, and this problem persists. Do I need to take it to highway speeds (65mph+ in CA) to get it up to temp?

[dburgess1231]

Originally Posted by edxmon

I've let let "Warm up" for way longer than that, but like I mentioned before I'v only every ridden it around my block/neighborhood for 1-2hrs at a time at max 30mph, and this problem persists. Do I need to take it to highway speeds (65mph+ in CA) to get it up to temp?

No it will be warm in like 10-15 mins.... Sounds like you are not down shifting as you brake around turns, so the rpms are too low for a higher gear. Can this be the case?

[edxmon]

Originally Posted by dburgess1231

No it will be warm in like 10-15 mins.... Sounds like you are not down shifting as you brake around turns, so the rpms are too low for a higher gear. Can this be the case?

What do you mean down shift as I brake? This problem is only when taking off from a dead/0mph stop. I usually leave the bike in 1st gear and hold the clutch for a stop sign, this whole issue is about taking of from first. I think you might have misunderstood something, unless there is a gear lower than 1st I don't know about.

[csmith12]

Originally Posted by edxmon

I've let the bike "Warm up" for way longer than that, but like I mentioned before I'v only every ridden it around my block/neighborhood for 1-2hrs at a time at max 30mph, and this problem persists. Do I need to take it to highway speeds (65mph+ in CA) to get it up to temp?

Not at all.

I start my bike with choke. Finish putting on gear and such (3 or 4 mins tops), hop on and have none of the issues you describe.

If your riding for 1+ hours and it still doing that, something isn't right or your not giving it enough throttle to launch from a stop. Since your new to this, try giving it more throttle to get your rpms up as DaBlue1 stated. It's all part of learning to ride.

Hey! Speaking of learning, did you take the MSF? If not you really should, it's a great place to start.

And as for what dburgess1231 said. Yea... I guess for the engine to fully warm the block through and through maybe. But I will stand by what I stated early. 3-5 minutes and you should be able to PIN it. Don't make me go film it.

[edxmon]

Originally Posted by csmith12

Not at all.

I start my bike with choke. Finish putting on gear and such (3 or 4 mins tops), hop on and have none of the issues you describe.

If your riding for 1+ hours and it still doing that, something isn't right or your not giving it enough throttle to launch from a stop. Since your new to this, try giving it more throttle to get your rpms up as DaBlue1 stated. It's all part of learning to ride.

Hey! Speaking of learning, did you take the MSF? If not you really should, it's a great place to start.

And as for what dburgess1231 said. Yea... I guess for the engine to fully warm the block through and through maybe. But I will stand by what I stated early. 3-5 minutes and you should be able to PIN it. Don't make me go film it.

It's in my plans to take the MSF course, but I JUST registered the bike under my name 2 days ago and the charged me ~$270 dollars, so I'm trying to ration my money 'till summer, the MSF course here in CA is $250.

[cbdallas]

Ok, you're ruled out the 'cold-natured' issue. Tell us about your acceleration style. How high are you revving it, & how aggressive are you being with the clutch? If you're not giving it enough throttle before you enter the friction zone in the clutch, you may be bogging it down. If you're allowing it to get below 2500 rpms and then squeezing the throttle hard with the clutch fully engaged, you're lugging the engine, which can feel like it's about to die. I'm not suggesting that you need to be doing 8,000 rpm launches, but it also doesn't like to be lugged.

[dburgess1231]

Originally Posted by csmith12

Not at all.

I start my bike with choke. Finish putting on gear and such (3 or 4 mins tops), hop on and have none of the issues you describe.

If your riding for 1+ hours and it still doing that, something isn't right or your not giving it enough throttle to launch from a stop. Since your new to this, try giving it more throttle to get your rpms up as DaBlue1 stated. It's all part of learning to ride.

Hey! Speaking of learning, did you take the MSF? If not you really should, it's a great place to start.

And as for what dburgess1231 said. Yea... I guess for the engine to fully warm the block through and through maybe. But I will stand by what I stated early. 3-5 minutes and you should be able to PIN it. Don't make me go film it.

yeah mine is good in 5 mins on a cold day. I was just saying it doesnt take longer than the 10-15 at all. there is something else going on because it isnt that the bike isnt warm and ready ha.

[edxmon]

Originally Posted by cbdallas

Ok, you're ruled out the 'cold-natured' issue. Tell us about your acceleration style. How high are you revving it, & how aggressive are you being with the clutch? If you're not giving it enough throttle before you enter the friction zone in the clutch, you may be bogging it down. If you're allowing it to get below 2500 rpms and then squeezing the throttle hard with the clutch fully engaged, you're lugging the engine, which can feel like it's about to die. I'm not suggesting that you need to be doing 8,000 rpm launches, but it also doesn't like to be lugged.

This might be a big part of it, I'm certainly not used to the high revving nature of the 250. I'll try to be more aggressive with the throttle and let the clutch out smoothly. You think this would explain why the power kicks in after a delay though? First I'm barely rolling along, 2-3 seconds later it feels as if I had punched it, but this whole time the throttle has been kept constant

[csmith12]

Originally Posted by dburgess1231

yeah mine is good in 5 mins on a cold day. I was just saying it doesnt take longer than the 10-15 at all. there is something else going on because it isnt that the bike isnt warm and ready ha.

it's all good brah, no harm no foul

[cbdallas]

Originally Posted by edxmon

This might be a big part of it, I'm certainly not used to the high revving nature of the 250. I'll try to be more aggressive with the throttle and let the clutch out smoothly. You think this would explain why the power kicks in after a delay though? First I'm barely rolling along, 2-3 seconds later it feels as if I had punched it, but this whole time the throttle has been kept constant

Honestly, I'd have to know what the exact circumstances are in order to tell you if you have a problem or not. I know how a brand-new, perfect-running 250 behaves (I've had 4, one brand new out of the crate) and I know how they can act when they're cold or improperly tuned. I also know that no two of them behaved the same.

If you're launching at low RPMs, giving it full clutch engagement, then rolling hard on the throttle, you're gonna be waiting until the engine has entered its power band before you're going to feel anything significant. If you do that when the engine's still cold, it's going to protest. But...if you're launching at higher rpms and you're still feeling a lag, you may have a carb problem. I attempted the carb shimming trick on my 2005, and it created an obvious dead spot just above idle that made it very difficult to get a smooth launch, so I took the shims out. But that experience taught me how little it takes to screw up how the bike runs. You MIGHT have an issue with your carb slides , or one or more jets may be dirty or clogged, but I can't say that with any certainty because I'm not sitting in the seat experiencing what the bike's doing. It could be your fault, it could be the bike's fault. Start with adjusting your riding technique, and see if that doesn't alleviate the issue.

[edxmon]

Originally Posted by cbdallas

Honestly, I'd have to know what the exact circumstances are in order to tell you if you have a problem or not. I know how a brand-new, perfect-running 250 behaves (I've had 4, one brand new out of the crate) and I know how they can act when they're cold or improperly tuned. I also know that no two of them behaved the same.

If you're launching at low RPMs, giving it full clutch engagement, then rolling hard on the throttle, you're gonna be waiting until the engine has entered its power band before you're going to feel anything significant. If you do that when the engine's still cold, it's going to protest. But...if you're launching at higher rpms and you're still feeling a lag, you may have a carb problem. I attempted the carb shimming trick on my 2005, and it created an obvious dead spot just above idle that made it very difficult to get a smooth launch, so I took the shims out. But that experience taught me how little it takes to screw up how the bike runs. You MIGHT have an issue with your carb slides , or one or more jets may be dirty or clogged, but I can't say that with any certainty because I'm not sitting in the seat experiencing what the bike's doing. It could be your fault, it could be the bike's fault. Start with adjusting your riding technique, and see if that doesn't alleviate the issue.

Werd, like I said, I am probably trying to take off with the RPM too low, it costs me nothing to change my technique so I'll try that first. Since the bike is used, a carb cleaning is in order anyway so that'll be next.
God bless guys.

[Motofool]

Originally Posted by edxmon

.........If it's idling and I try to give it a large amount of throttle suddenly the bike dies. If I smoothly raise the rpm to 3000+ then gas it suddenly everything is fine and the engine responds immediately.

Your bike is starving for fuel.

When you open the throttle, more air than fuel moves into the engine, making the mix lean and the engine weak.

The passages in the carburetor could be partially clogged.

[edxmon]

Originally Posted by Motofool

Your bike is starving for fuel.

I see, from what I gather shimming the needles will quench its thirst for fuel?

[DaBlue1]

Originally Posted by edxmon

This might be a big part of it, I'm certainly not used to the high revving nature of the 250. I'll try to be more aggressive with the throttle and let the clutch out smoothly. You think this would explain why the power kicks in after a delay though? First I'm barely rolling along, 2-3 seconds later it feels as if I had punched it, but this whole time the throttle has been kept constant

Originally Posted by edxmon

Werd, like I said, I am probably trying to take off with the RPM too low, it costs me nothing to change my technique so I'll try that first. Since the bike is used, a carb cleaning is in order anyway so that'll be next.
God bless guys.

Originally Posted by edxmon

I see, from what I gather shimming the needles will quench its thirst for fuel?

Originally Posted by DaBlue1

A stock Ninja has very little power in the low rpm range. A good & common rpm to launch the bike is close to 3k and above. Trying to launch the bike just off of idle can be done but as you can tell it's not good in a traffic situation. Launching the bike at a higher rpm speed will require a little more twisting of the throttle, something you may have to get used to as a new rider. One caveat of the CV type carbs is a tiny lag in throttle response when snapping open the throttle. This is normal and is due to the slides in the carbs being vacuum operated as opposed to being mechanically operated by the throttle cable.

Being that you bought the bike used a little preventive maintenance should be in order. One item that is included in that maintenance checklist is the air filter. And yes, a super dirty air filter can cause throttle response problems. It is easy to check and clean or just replace. Shimming of the needles will help a little with throttle response in the low rpm range (about 1/8 throttle) but is most effective in the 1/4-3/4 throttle (midrange).

My suggestion would be to continue practicing riding the bike and getting more familiar with the clutch, throttle and engine operating speeds. Once you are comfortable with that then look at doing intake mods.

If you just remember to twist the throttle more you'll find that the bike is smooth and won't snap your neck when taking off. Hope that helps.

[edxmon]

Originally Posted by DaBlue1

If you just remember to twist the throttle more you'll find that the bike is smooth and won't snap your neck when taking off. Hope that helps.

10-4. Got some SS shims and a K&N filter. I reckon these should help some, paired with a more aggressive take off from stops

[Motofool]

Leave it in stock form for a while.

Those things just introduce more variables into the problem.

A good carbs' clean up should suffice.

[DaBlue1]

Originally Posted by edxmon

10-4. Got some SS shims and a K&N filter. I reckon these should help some, paired with a more aggressive take off from stops

My bike is shimmed, snorkel removed, and with a Pipercross air filter. Trust me, taking off at 3k is hardly aggressive.

[edxmon]

Originally Posted by DaBlue1

My bike is shimmed, snorkel removed, and with a Pipercross air filter. Trust me, taking off at 3k is hardly aggressive.

I guess so, when the redline is 13k on the bike. I'm used to a car with 8k red line

[alex.s]

unless the bike is dead cold (like under 40 degrees), it should run fine within a minute of running. if it doesnt its either clogged up, or tuned improperly. if its an 08 im guessing both. we just took apart a stock set of carbs and it turned out that one of the mix screws had screwed itself all the way in. still had factory screw covers on when we pulled them. ran pretty much how you describe. we cleaned it, set the mix screws, and synced it and it ran like a brand new bike. warmed up to run well in only a few seconds vs seemingly taking upwards of 5-10 minutes to warm up before. and this was on a bike that is ridden pretty much every day

[edxmon]

Originally Posted by alex.s

unless the bike is dead cold (like under 40 degrees), it should run fine within a minute of running. if it doesnt its either clogged up, or tuned improperly. if its an 08 im guessing both. we just took apart a stock set of carbs and it turned out that one of the mix screws had screwed itself all the way in. still had factory screw covers on when we pulled them. ran pretty much how you describe. we cleaned it, set the mix screws, and synced it and it ran like a brand new bike. warmed up to run well in only a few seconds vs seemingly taking upwards of 5-10 minutes to warm up before. and this was on a bike that is ridden pretty much every day

yo Alex! Then I guess I know exactly what to ask for help with at the next Tech Day :P eh?

[MikeBudd]

Check the mixture screws. Sync the carbs. If that doesn't work, shim the needles.