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Discussion Starter #1
I really love the 300 except for two things.

1) the seat where it meets the fuel tank seems pull my nuts in and it's not comfortable

but I am wondering about -

2) it is a bit rough coming on and off the throttle. I've found this with other cheap fuel injected bikes.
Does anyone else share this issue? I don't usually find myself needing more power but if a fuel controller makes the throttle smoother I would consider buying one.

I have the stock exhaust and will probably keep it that way (don't need extra attention from the cops)
 

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Discussion Starter #3
I suppose I'm mainly trying to reduce the crispness, make it more gentle to ride at low speeds when you're on and off the throttle in the 0-10% range
 

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I think a lot of the smoothness is drivetrain lash. Make sure your chain is tensioned properly. Also, this bike, probably ot save costs, I don’t think has a cush drive on the rear sprocket hub. Also no back torque limiter (slipper clutch).

To me it doesn’t see that jerky really. Maybe more than the KLX250S I had, but a lot less than the BMW R1200RT and Ninja ZX9R. Similar ot my CBR600F4i.

Keep in mind it’s a very low first gear.

I don’t think a controller will do a whole lot to smooth it out in that way.
 

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I think a lot of the smoothness is drivetrain lash. Make sure your chain is tensioned properly. Also, this bike, probably ot save costs, I don’t think has a cush drive on the rear sprocket hub. Also no back torque limiter (slipper clutch).

To me it doesn’t see that jerky really. Maybe more than the KLX250S I had, but a lot less than the BMW R1200RT and Ninja ZX9R. Similar ot my CBR600F4i.

Keep in mind it’s a very low first gear.

I don’t think a controller will do a whole lot to smooth it out in that way.
Actually, these bikes do have rubber dampeners in the drive hub. I'd agree that adding a fuel controller isn't likely to change anything regarding throttle smoothness.

As kiwi rider suggested, making sure that there isn't too much free play in the throttle cables is the first thing I'd check.
 

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First, thanks Motoguy128 and kiwi_rider for things to check. First gear on my F is jerky, but I mostly chalk that up to inexperience.

Second, I picked up a Bazzaz for $125 from an individual who was not happy with the swap, so you can def. find fuel controllers for a discount. I may play around with it soon, or keep it boxed till an intake and muffler. I'm actually curious to have a baseline dyno reading, but afraid a stock 300 ridden by a newb is disqualifying somehow ("You have to be this tall to ride the dyno").
 

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Yep definitely has cush drive. Doing motogymkhana compresses them more than usual so you get even more lash. But we're talking <2mm at the wheel radius - bugger all really. Chain slack is the main thing. I've gotten into the habit of using the clutch a lot more to mitigate the effects of chain lash. A quick half pull in of the clutch when going off throttle smooths things out.
An extra tooth on the front cog might help too though I've not gone down that route. The other thing you could try is a modified throttle cam - forgot the name - it has a smaller radius at the start so the initial twist of the wrist has less effect.
 

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Discussion Starter #10
Yep definitely has cush drive. Doing motogymkhana compresses them more than usual so you get even more lash. But we're talking <2mm at the wheel radius - bugger all really. Chain slack is the main thing. I've gotten into the habit of using the clutch a lot more to mitigate the effects of chain lash. A quick half pull in of the clutch when going off throttle smooths things out.
An extra tooth on the front cog might help too though I've not gone down that route. The other thing you could try is a modified throttle cam - forgot the name - it has a smaller radius at the start so the initial twist of the wrist has less effect.
Yep I often choose to use the clutch also when coming back on the gas. I have already gone up to the 15t on the front so its less buzzy on the freeway.
The throttle cam sounds like a really neat idea...
 

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I really love the 300 except for two things.

1) the seat where it meets the fuel tank seems pull my nuts in and it's not comfortable

but I am wondering about -

2) it is a bit rough coming on and off the throttle. I've found this with other cheap fuel injected bikes.
Does anyone else share this issue? I don't usually find myself needing more power but if a fuel controller makes the throttle smoother I would consider buying one.

I have the stock exhaust and will probably keep it that way (don't need extra attention from the cops)
Quote.."" the seat where it meets the fuel tank seems pull my nuts in and it's not comfortable""

Interesting...do you suppose your "user name" is the issue with the problem above? :devil:

Sorry..... I could not let that thought slip by....:D
 

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Glad to see it's not just me who finds it difficult to keep it smooth at low revs. Compared to my old 2 stroke it's extremely jerky in Bangkok traffic and the standard gearing doesn't help, which is why I find myself opting for my old Honda Tena 2 stroke or even my Yamaha Spark for the trip across Bangkok to work, leaving the CBR for longer jaunts out of the city.
 

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Glad to see it's not just me who finds it difficult to keep it smooth at low revs. Compared to my old 2 stroke it's extremely jerky in Bangkok traffic and the standard gearing doesn't help, which is why I find myself opting for my old Honda Tena 2 stroke or even my Yamaha Spark for the trip across Bangkok to work, leaving the CBR for longer jaunts out of the city.
Do you find that in city traffic you're riding in first gear a lot?
 

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Deceleration fuel cut off

I don't remember my CBR being too bad for jerkiness/hesitation on and off the throttle around town as long as the usual suspects like chain and throttle cable slack were in order.
Typical of a lot of the latest crop of bikes my Ninja 400 suffers from this condition much worse.

Because of the tightening emission laws engineers have to lean out the ECU fuel map at certain speed and load points where emissions are measured. Deceleration is one of these points.
Ideal fueling wets the cylinder head intake ports, which smooths out initial throttle application when you get back on the gas. However, the latest emissions laws remove this wetting feature, creating hesitation and a harsher response because the engine is waiting for the mixture to arrive in the combustion chamber. Lag basically.
Bring back carbs I say! :devil:
 

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I don't remember my CBR being too bad for jerkiness/hesitation on and off the throttle around town as long as the usual suspects like chain and throttle cable slack were in order.
Typical of a lot of the latest crop of bikes my Ninja 400 suffers from this condition much worse.

Because of the tightening emission laws engineers have to lean out the ECU fuel map at certain speed and load points where emissions are measured. Deceleration is one of these points.
Ideal fueling wets the cylinder head intake ports, which smooths out initial throttle application when you get back on the gas. However, the latest emissions laws remove this wetting feature, creating hesitation and a harsher response because the engine is waiting for the mixture to arrive in the combustion chamber. Lag basically.
Bring back carbs I say! :devil:
My 300 R is not to bad either as far as jerkiness goes. I did take out a CBR 250 (new) in 2014 and that bike was terrible. However I have noticed...maybe twice since I have owned the bike these last close to 3 years that when I go to accelerate from a dead stop (I roll on the throttle)...the engine chugs (backfires) once and dies. Like I said it has only happened maybe twice. At that point I have not let out the clutch yet....
 
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