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Discussion Starter · #1 ·
When I got my 2017 R3 a little over a year ago it felt kind of jerky at low throttle levels - I give it a tiny bit of gas and it jumps forwards, I let off on it just a tiny bit and it jumps back. I thought it was just because I was new and didn't know how to ride it, but once I got better it never went away. Then I thought maybe it was just cause it's a smaller sized bike. Talking to a guy at a local parts store and he thought it sounded like maybe it needed a tune-up like when you change out the exhaust (but it's still stock, bike only had 200 miles when I got it).

Reading the forum posts people say how not jerky the bike is (at least for earlier models), except this one post I found Yamaha and their sh!tty injector cut. where it sounds like they have a similar problem (except I live where it's almost always flat so hills aren't the issue).

Is this just how the bike is supposed to ride? Do I really need to spend hundreds of dollars to flash the ECU? It's really annoying and I'm constantly using the clutch to soften it out but it seems like it should just be smoother than that.
 

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Like other motorcycles, the R3s ECU is programmed to 'cut off' the fuel injectors when off-throttle. You're describing perfectly what happens as the engine's backpressure 'brakes' and slows the bike. That's not a very technical description, but it's 'normal' for the R3.
The only 'cure' for the problem is to have the ECU re-flashed to delete/reduce the way it cuts fuel to the injectors.
My 2015 has ridden that way since new. Since I'm not willing to pay for a re-flash, I just live with it and try to stay on throttle.
Sorry I don't have a quick fix. Maybe someone else can chime in to let us both in on their secrets.
 

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Glad to know at least it's not just me. Might think about flashing the ECU, seems like a lot of money for something that shouldn't be a problem to begin with though. If/until then I'll just keep using a ton of clutch I guess.
 

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I hate to say it...... Spend the couple hundred bucks, and get the ECU flashed. Even on a "bone-stock" R3 the difference is VERY noticeable!!! I kept hearing people talk about how the "engine-braking" on the R3 was so bad.... I didn't realize how "bad" it was, until I got the ECU flashed, and had the engine-braking "removed".... It makes the bike soooo much easier to ride, and does everything better than stock. The engineers at Yamaha did the best they could to make an affordable/fun bike that meets the government mandated EPA criteria. Essentially, those engineers were handcuffed as to what they could do. We are fortunate to have the resources to spend a small amount of money, to make this bike run as it should have from Day 1. It takes a very minimal amount of effort to remove your ECU, and mail it to a reputable tuner. I prefer 2WDW, but there are others out there as well. "Just do it" :cool:
 

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A lot of modern bikes suffer this effect due to emission regulations. It's changing between super lean barely idling and on the gas, and it's the dreaded "on/off" effect that is mentioned so often.
 

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I guess I've just gotten use to riding a lot of different bikes and larger bikes, the R3 never seemed jumpy by comparison to what I was used to dealing with, especially on my 636 lol. That said, flashing my ECU definitely smoothed it out noticeably, and I love having use of the entire RPM range as an added benefit. Much faster now.
 

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When I got my 2017 R3 a little over a year ago it felt kind of jerky at low throttle levels - I give it a tiny bit of gas and it jumps forwards, I let off on it just a tiny bit and it jumps back. I thought it was just because I was new and didn't know how to ride it, but once I got better it never went away. Then I thought maybe it was just cause it's a smaller sized bike. Talking to a guy at a local parts store and he thought it sounded like maybe it needed a tune-up like when you change out the exhaust (but it's still stock, bike only had 200 miles when I got it).

Reading the forum posts people say how not jerky the bike is (at least for earlier models), except this one post I found Yamaha and their sh!tty injector cut. where it sounds like they have a similar problem (except I live where it's almost always flat so hills aren't the issue).

Is this just how the bike is supposed to ride? Do I really need to spend hundreds of dollars to flash the ECU? It's really annoying and I'm constantly using the clutch to soften it out but it seems like it should just be smoother than that.
When I got my 2017 R3 a little over a year ago it felt kind of jerky at low throttle levels - I give it a tiny bit of gas and it jumps forwards, I let off on it just a tiny bit and it jumps back. I thought it was just because I was new and didn't know how to ride it, but once I got better it never went away. Then I thought maybe it was just cause it's a smaller sized bike. Talking to a guy at a local parts store and he thought it sounded like maybe it needed a tune-up like when you change out the exhaust (but it's still stock, bike only had 200 miles when I got it).

Reading the forum posts people say how not jerky the bike is (at least for earlier models), except this one post I found Yamaha and their sh!tty injector cut. where it sounds like they have a similar problem (except I live where it's almost always flat so hills aren't the issue).

Is this just how the bike is supposed to ride? Do I really need to spend hundreds of dollars to flash the ECU? It's really annoying and I'm constantly using the clutch to soften it out but it seems like it should just be smoother than that.
So I started having this trouble later on and couldn't understand why. Then one of the mechanics I go to told me that it's because of the dumb-ass lock downs due to Covid clownery. Since the bike was just sitting there for more than a year, sediment in the fuel tanks went and clogged up the injectors. So I got a throttle body sync done and then got the injectors cleaned. Now the bike is even smoother than when I bought it and moves comfortably even at low speeds.
That's what worked for me. Didn't touch the ECU at all.
 

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So I started having this trouble later on and couldn't understand why. Then one of the mechanics I go to told me that it's because of the dumb-ass lock downs due to Covid clownery. Since the bike was just sitting there for more than a year, sediment in the fuel tanks went and clogged up the injectors. So I got a throttle body sync done and then got the injectors cleaned. Now the bike is even smoother than when I bought it and moves comfortably even at low speeds.
That's what worked for me. Didn't touch the ECU at all.
I'm going to say this as respectfully as I can..... "New" motorcycles are not shipped with fuel in the fuel system. There are far too many variables to make it a cost effective option (even before COVID-19). Sometimes motorcycles will sit in a warehouse for well over a year being purchased. If there was fuel in the system, that fuel would deteriorate, and deteriorate the seals in the fuel system. Asian manufactures have spent millions of dollars during the 1980's trying to combat this situation. Fuel injection systems have helped. Unfortunately, oil refineries have been able to produce a "lesser" product, because fuel injection systems run at a MUCH higher pressure than a "vacuum" pressure carburetor, that relies on suction to make it work.They can refine a "lesser" product (for less cost), and make more money/profit. It's a sad situation-
 

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When I got my 2017 R3 a little over a year ago it felt kind of jerky at low throttle levels - I give it a tiny bit of gas and it jumps forwards, I let off on it just a tiny bit and it jumps back. I thought it was just because I was new and didn't know how to ride it, but once I got better it never went away. Then I thought maybe it was just cause it's a smaller sized bike. Talking to a guy at a local parts store and he thought it sounded like maybe it needed a tune-up like when you change out the exhaust (but it's still stock, bike only had 200 miles when I got it).
You have a few things to keep in mind while riding. A.) The R3 is light, so changes in power will cause an immediate response. B.) The R3 has an engine with 11.2:1 compression ratio, which will generate significant engine braking off throttle. C.) The R3 utilizes a digitally controlled fuel system that optimizes fuel use for economy and emissions (both good things, for those of us who wish to see gas powered bikes remain on the road.) D.) Fuel injected bikes behave differently than carbed bikes. With carbs, airflow through the venturi feeds fuel into the intake at all throttle settings, including off throttle. With fuel injection, the amount of fuel is controlled by firmware that delivers fuel based on throttle position, RPM, O2 and temperature sensors to produce the optimal A/F mixture for a given load and engine speed. This means that it can actually cut fuel off completely when the throttle is closed - something carbed bikes never could do, so the feel between the two approaches is quite different.

That understood, there are two things that will help.

First, you may benefit from adjusting the throttle cable to reduce the amount of free play at the closed throttle position. It should be around .060". Over time, it loosens up and the closed throttle position comes at you sooner than expected, creating a jerky feel.

Second, consciously work on throttle control to avoid completely closed throttle when you are decelerating, until you are below 5,000RPM. Even the slightest bit open keeps the fuel system engaged and the engine braking limited only to the reduced demand/decelerating RPM. with a little practice, one can slow down smoothly, without the hard grab of the fuel cutoff on deceleration, which eliminates the concurrent over-reaction on-throttle.Adjusting the throttle cable makes this much easier and more effective.

If you have good fuel (not been sitting for more than a few weeks), a properly adjusted throttle control, and are practiced in your throttle work while riding, the problem will go away - while you maintain the fuel economy programmed into the ECU. Jumping immediately to mods and ECU flashing is not necessary, or even justifiable for an otherwise stock bike.

I had an Aprilia Falco that was so bad at off-throttle behavior and on-off jerkiness, the factory fitted the bikes with slipper clutches to keep from slamming riders into the ground when they chopped the throttle. Even then, learning to manage throttle position and getting a feel for smoothly controlling off-throttle position was key to enjoying that bike well. The R3 makes it even more important, as it has no slipper clutch (no this is not a needed modification either) and is significantly lighter. The habits you learn here will not only make riding the R3 better, it will carry over later fuel injected bikes.
 
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