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Throttle Too Sensitive on 2009 Nightster

34K views 49 replies 29 participants last post by  shoney  
#1 ·


Hey All. New here. Just took delivery of a 2009 Nightster in Vivid Black. It's all stock right now and it'll probably stay that way until the bike and I get back from a year living, working, and riding in Germany and Ireland.

Anyway, I feel like my throttle is far too sensitive. It's either on or off and I have to micro-adjust the throttle within a very tiny area in order to maintain speed, accelerate from a stop properly, and so forth. When I go over a bump, the bike jerks a lot because my hand moves. I'd like more "room", or perhaps better said, less "sensitivity." I'd also like more weight on the throttle - which might solve the problem I'm having.

Now, I've heard that the throttle cable will stretch a little over time and that this sensitivity will reduce on its own. I also heard there is a star-shaped knob under the throttle that functions to adjust the sensitivity a bit.

I'm looking for an evenly-increased application of power from the throttle. Now, within, oh, the first half inch of turn, it launches the bike. I want it to be kind of like my car where if I slam on it, it launches. If I slowly press the peddle, it slowly accelerates. I simply cannot get into 1st gear from neutral right now w/out either launching or sputtering the engine. There is no in-between. (And I know a car's engine gets throttle a bit differently and is heavily computer controled, but even the old carbed Mustangs I've driven could launch or accelerate slowly.)

My first bike was a 198X Honda something-or-other with 300cc's. I realize the Nightster is far more powerful, but that doesn't mean it needs to jerk around. The Honda "thing" had a smooth throttle application - perhaps not sensitive enough.

There's got to be a way to get my Harley to be just right! Right? Anyone have any ideas how I can make this fix? I don't mind going to the dealer if I have to - but I'd like to avoid that because, well, I don't want to.

Also, if you could add, what's the fix to prevent the corrosion I'm reading about on the wheels and in the fuse box?

Appreciate the help all!

 
#2 ·
That "star" knob just deadmans your throttle, locks it place so you can scratch your nose.
Don't know what you can do other than get a HD twin cam 96. Sporsters are very jumpy.
Nature of the beast.
 
#3 ·
Well come to think you got EFI. Maybe the program could be tweeked. But your complaint is exactly why I keep my 04 1200 around. twist the wick and be in warp drive.
 
#4 · (Edited)
Well I just found this forum today also and it looks great. I drove my Street Bob home today for the first time, and having an older carb'ed Honda I think I know exactly what you are talking about. The old Honda 750c Custom would go, but there was a definite difference with the throttle. The Honda cables were older and not as smooth. (felt thick when you turned the throttle- sorry, best adjective I could come up with) The new Harley has a very crisp throttle responce where the honda wasn't. Personally I love it. I did notice that when I hit a bump the smallest movement of hand would drastically change my speed. I put 75 miles on it today and just worked on making riding adjustments to compensate for the new way this bike rides and responds. I know this doesn't really help, but I believe it is just the difference in a bike having carbs and one with computer control. Hopefully I'll have the 500 mile break in done this weekend, so I can take full advantage of the entire power band.

Good luck and enjoy.
 
#5 ·
Hey there Sirboom,

I test rode a Nightster and agree with your comments. I believe the reason that occurs is due to the horsepower to weight ratio. In other words you got alot of power on a light bike. Until the VROD came along the 1200 Sportsters were the fastest Harleys made. An under powered bike will have much smoother throttle response due to a lack of power. So I think it's the nature of your beast. With some practice, I bet you can smooth it out with some time in the saddle.
 
#6 ·
Thanks for the advice. What I've done so far is turn the "star knob" just enough where the throttle is manageable. I have the stock handles, so what I'm going to do next is get bigger, heavier handles. Harley sells some all metal, thicker handles that weigh more than my rubberized, skinny things that came with the bike. I rode for 50-ish miles yesterday and the more miles I go, the more I get used to it. I still don't like and am not willing to accept (yet...) the fact that I go over a bump and the bike jerks with my hand movement. The Nightster's suspension is a rock compared to my neighbor's 2004 Sportster Custom, so I need to do something. His '04's throttle was perfect (with the stock handles). His handle bars were also way to narrow... but that's another story.

I'll update if the heavier handles work on this post. I have 200 miles on it, so I'm thinking over some time the throttle will improve both because I get used to it and because it just, I guess, gets better....

Once I take care of some additional lighting, I'll post pix.
 
#7 ·
09 Nightster Touchy

I am new here. I wanted to sign up after reading the nightster thread about the sensitive throttle. :ride



I purchased a 2009 nightster about 2 weeks ago and have got 200 miles on it. I thought it was just me but I am glad to hear its not. I had alot of slop in my throttle when I purchased it which I adjusted at the cable, however, it did take me a while to get used to it. Going over bumps and maintaining a steady speed....a tiny bit might as well be a mile....real sensitive!!! But some of the responses I read here contained good info. I think it is power to weight as well and I am hoping after a little more time in the saddle and on the throttle the bike and I will get used to each other.
 
#8 ·
I really think as you get used to the bikes and more relaxed it wont be a bother, your wrist action will become like a shock absorber for the bumps and automatically keep a steady throttle without you even realizing it.
I changed the handle bars on my 04 1200 couple inches higher and a couple inches wider and I could actually use the mirrors.
 
#9 ·
A couple of weeks ago, my wife decided to get her license after watching me ride for 20 years. She's 5'2" so we got a Nightster due to it's low saddle height. She feels (and I agree) that the throttle is too sensitive. I have already put larger grips on it (as well as SE slip-ons, SE air cleaner, and a V&H fuel pack). Needless to say, it hauls butt, however, the throttle sensitivity is exacerbated by the increase in horse power from the performance mods and the greater leverage she has on the throttle from the larger grips.

The stiff suspension adds to the problem too. I already lowered the tire pressure and softened the rear springs by moving the cams. Perhaps a cushier seat would help absorb some of the jarring.

I was hoping someone had a remedy for this, but from the previous posts, it looks like the only solution is to tighten the throttle lock and otherwise get used to it.

Well, I'll increase her life insurance and see how it goes!
 
#13 ·
The larger grips will actually make the sensitivity worse because it allows you to apply more torque to the throttle by increasing your leverage. I htink it's a matter of getting used to it. I found that after I rode the buke for about 30 minutes, the herky-jerky stopped ... my technique had improved.
 
#12 ·
My son's Yama-hammer R1 abruptly gives about 100 extra hp, just as you cross 7000 rpm. When he first got it, he complained they truly expect everybody who buys one of these to die on it.. said it felt exactly like being hit from behind. He also kept telling me that the slightest touch on the throttle, if it took you over 7000, If you were going around a corner or on a hiway ramp and leaned over, the sudden brutal acceleration could stand you up straight and throw you over the guardrail.

I kept saying that's impossible, his bike is not fly by wire, he actually controlls throttle butterflies, so I said I don't see how manifold vacuum can change like that.

He took it all apart and found there was a second set of throttle butterflies above the ones he's controlling, and they open by the computer at 7000 rpm. Craziest thing I ever heard, the throttles he controls are only dealing with partial atmospheric pressure until 7000 and then he gets it all. It's like having automatically applied afterburners or 100hp nitrous.
 
#14 ·
Bob And Jennifer

I was riding this weekend and I had been having the same issue you were having with the throttle being very touchy. I have found if I move my right hand up pretty far, closer to the handle bar, the throttle isn't as sensitive, it gives me more support, at least until I get use to.
Let me know how you do.
Carol
 
#17 ·
I was riding this weekend and I had been having the same issue you were having with the throttle being very touchy. I have found if I move my right hand up pretty far, closer to the handle bar, the throttle isn't as sensitive, it gives me more support, at least until I get use to.
Let me know how you do.
Carol
My wife said the same thing. If she holds the grip closer to the controls, she does better.

Easy thing to do.
 
#15 ·
Bob, that's priceless! I can hear it now, "Uh honey, I did a few mods on the bike, and well uh, after watching you ride - I've decided to increase your life insurance. You understand dear - we'll just see how it goes."

I'm sorry, I couldn't resist!
 
#18 ·
i have a 2008 custom sportster i had the same problem with a touchy thottle. i fitted a thunder max ecm to my bike the problem is slowly disapering as the auto tune adjusts it self. i use to hate riding my bike with the thottle the way it was. i think it may have been running a bit lean at part thottle plus the shity roads around here. the thunder max is great a big diffrence from the harley ecm
 
#19 ·
jerky throttle, mine to

My 05 Sporty has a jerky throttle to, i put kuriakin iso's with palm rockers on it and it helped a lot. The palm rocker kind of helps control your wrist movement. You will get used to it in time. The sporty has a lot of torque and it's ready to go, happy trails. :ride
 
#20 ·
Originally Posted by Bob&Jennifer
The larger grips will actually make the sensitivity worse because it allows you to apply more torque to the throttle by increasing your leverage.
I don't agree that a bigger grip would not help.
If you'll do a test I believe you'll find that's exactly what you need.

The problem is not that the grip is too easy to turn,
the problem is that the rider just has a hard time moving the throttle
in small enough increments, doubling the diameter will cut the sensitivity in half.

A 1" diameter grip has a circumference of 3.14"
a 2" diameter grip has a circumference of 6.28"

so a 1/16" twist has half the effect with twice the diameter.

The problem with any adjustment knob of very small diameter,
like on a radio tuner dial, it is hard to move it a just a smidgeon.
It's much easier to do very fine adjustments when the dial is larger.

You wouldn't want to change grips to test this, but you could get a piece
of dense neoprene foam tube at WalMart, it comes in black so it wouldn't
have to look too goofy, the stuff that's used to cushion bicycle frames and
handlebars on kid's bikes and overwrap the stock grips to check out the effect.

I'd bet that putting on a comically oversized grip for testing
would be so much easier to use that you might consider keeping it.

An even easier test, wrap the throttle grip with an ace bandage to double
it's bulk for a quick test that you already have the necessary materials.
 
#21 ·
I agree with Nathan. Increasing the grip diameter means you have to move it more to do the same thing, making it less sensitive.

I also agree with those who have said move your hand inwards on the grip till it touches something. A little friction will help to avoid the bump reaction.

The last thing that I do for different reasons, but it might help, is to put your forefinger on the brake lever. The schools will tell you not to do this. I do it because I have more than one bike, and this avoids me having to feel for where the lever is, but it also stabilizes your throttle hand a little.
 
#24 ·
I put the black diamond H-D grips on. They're larger than stock, and they improved both the feel of the bike and the jittery-ness. The larger circumference of the handles gives me more leeway to make adjustments. I also rotated my handlebars down for a bit more of a lay-down riding position. It's nice.
 
#25 ·
I own a 09 nighgtster and have no problem what so ever with the so called sensetive throttle problem! if you all think that the nightster`s have a sensetive throttle ,then don`t ever ,i repeat don`t ever ride a 500 cc twostroke motocross bike !!!!!!!!! I raced these beast`s in the expert class or a class .let me tell you that the nightster`s power does`nt even come close to what the power that the 500 had!!! violent power is the best way that i can describe it!!! people it all come`s down to throttle control !!! master that and you will have no problems at all!!!!!!
 
#26 ·
Well, before I could place rolls of toilet paper over the grips to simulate a comically large grip, my wife dropped her nightster. It's true. From a stop, she tried to turn left and pulled the throttle back as she turned the bars to the left. Needless to say, too much throttle while turning can land you in the ditch (after a 180)! Fortunately, she's OK ... bike's not so lucky, but it's cosmetic mostly.

It seems she had her wrist bent down so as she extended her arm to make the turn it straightened her wrist, the throttle went down, and so did she. Of course, the throttle sensitivity had a negative impact, so I'll be working on a solution for that as I repair the bike.
 
#27 ·
Tell her we're sorry to hear about it.
Almost everybody belongs to Drop Club.
Just not very many people talk about Drop Club.

It's much better to do it when there aren't 50 people watching.
 
#28 ·
True that - I'm not sure Bob & Jennifer were here when I told how I converted a planned roll-through an intersection into a sudden stop, forgot to pull the clutch, stalled and at a complete standstill, very gently fell off in front of 200 bikers in a gas station to great amusement all round :rofl::rofl::rofl:

Fortunately I was on my old beater Suzuki :hidesbehind

Not sure which was worse:stir
 
#29 ·
Ive got 48 hours to confirm a deal im gettin on a 2009 Nightster and was just wonderin (because of all the negative feedback from people i've been getting) if you regret getting the nightster compared to others. The bike is a good price range for me right now and it is my first Harley. Im about 5'10'' and have been told im too tall for the bike, anyway just wonderin if i can get more opinions on it from owners. Thanks
 
#30 ·
Did you look at the dyna custom the aren't that much more. I bought a sportster low and wish I had gone the extra 3grand. I'm 5'6".