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Discussion Starter · #1 ·
Hey all,

For the first time I am experiencing some weird Helmet turbulence on my GT above 85 MPH. It feels like there is a jack hammer on my head as my helmet gets battered around. To clarify, this did not just start, its the first time I tried taking my bike above 80 MPH.

Is this to be expected with all naked bikes (I have never owned or ridden a naked street bike before)? I feel like the bike does not want to go anymore after 85 MPH as I am getting battered all over the place. Feels like I am running against the wind with a piece of plywood in front of me.

I experienced all this riding with a buddy of mine to day as we were doing the Freedom Run. We were on route 80 and we had the highway to our selves, and he was just taking off leaving me behind and my bike felt like it had nothing. The sad part, his bike is a Suzuki Boulevard C50 (800CC and weighs 600+ pounds). He has a windshield, but does that make a big difference allowing him to cut through the wind and leave me in the dust at 90 MPH?

I have yet had the chance to try ton up speed, but feel as thought I am going to get blasted around. My last bike a Kawasaki Ninja 650R (65HP, 400 pounds) felt a lot faster on the highway, easily hitting 100 MPH.

Maybe I got a dud :)

Oh, I weight 198 pounds and have broad shoulders (but that should not make that much of a difference)
My helmet is an AVG Miglia Modular (did not have teh jack hammer effect with last bike)

Ok now I am just rambling.........
 

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If this is the first bike that you have riden without a fairing then the buffeting you are getting will be very prevelent to you, and this will show you how good fairings are, dont panic it will be something you will get used to and the more you ride the bike the more you will get used to the wind hitting you, wait till you have a 60,70 or 80 KLM cross wind that will get your attention,

PS: the little windscreen on the S4 is amasing and I really notice the differance between the sport and the S4 chalk and cheese. :D


Vale46

06 S1K
03 S4
 

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Yeah, there is more turbulence with a naked bike, but what you describe sounds excessive. Is it possible that your helmet is too large? A well fit helmet should be tight, many, if not most riders wear too large a helmet. This could cause excess buffeting. Or maybe it's the design of the helmet. You could try riding with another helmet, preferable a non-modular one, to see if it helps. Lastly, when accelerating hard, or cruising 80mph or more, I lean into the wind, getting closer to the bike. This helps with the wind and helps keep the front wheel down too when punching it.

Hope this helps.
 

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I always wear ear protection....I wonder if maybe your jacket or helmet strap is flapping against your helmet ?

Just a thought...:think:
 

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You haven't indicated what gear you were in @ 80 mph. If you're on a stock US GT, that means you're running the 15/39 sprocket setup. In sixth gear on a stock bike that's about 4K rpm, and the wind resistance can easily overcome the available power.

Your bike has a lot more power/acceleration but you'll have to drop it a cog or two to take advanatage of it. Many on this forum, myself included, have gone to a 14 tooth front sprocket which puts your engine into a little higher rpm bracket at cruising speeds, yielding more available power.

So far as the "jackhammer" goes, tighten your helmet strap and tuck in your shirt!:D Seriously, a good fitting helmet makes a huge difference out in the breeze.
 

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Perhaps weather conditions should also be taken into account?

I have had a succession of 'naked' bikes over the last few years & the effect of windblast is certainly more noticable at high speeds on windy days.

My GT1000 has the DP flyscreen (my 695 Monster had the carbon nose fairing) and I have no problem in achieving higher speeds, although there is definitely more comfort to be had from leaning forwards slightly at speeds over 80mph. I'm 5ft 9ins so perhaps I'm not sat up in the airflow as much as taller riders, you don't say how tall you are so I thought I'd throw this into the equation.

I agree with the other posters on the subject of helmet & clothing. Maybe you just need to increase your riding hours? The GT seems to be a bike that one appreciates increasingly the more time one spends on it (IMHO).

The GT1000 should easily achieve 100mph, but I have to be honest & confess that I rarely venture near such speeds. I value my licence and simply enjoy being able to appreciate the scenery whilst bend swinging in the countryside.
 

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Regarding the helmet jackhammer effect, if your helmet is ventilated you may need to close the vents when riding at high speed. I use an open face helmet with a face shield and have a similar problem, mainly in a headwind. Closing the vent helps.

Maybe the problem didn't occur with your last bike due to different ergonomics.
 

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Discussion Starter · #8 ·
Thanks for the responses guys.
Let me address some of your questions:

I am running with a 14T sprocket

When my friend pulled away from me he was going 60 MPH and accelerated to about 90 MPH. I was in 5 Gear going 60 MPH and it felt like it took a while to catch up to him,

My helmet fits OK, it was very tight, then it broke in, then I lost weight. Its not lose, its just not very tight at all. It does have one vent on top, which I will close to see if that makes a difference.

I am 5,9"
 

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Something isn't right here. Maybe several somethings.

My bike has stock sprockets and will easily accelerate to any speed that I ask of it. I have not yet ridden with a rider on another bike that could "leave me in the dust". It's always the other way around.

I did have to adjust my riding gear to the naked GT. Proper fit is everything. Some helmets just cut the wind better than others. You'll see more manufacturers adding sculpted lines to the exteriors of their helmets that help break up high speed air flow and thus helmet "snatch". (This is where you turn your head and the helmet pulls hard with the air flow, "snatching" your head to the rear.)

Sounds as though your helmet is too big. Mine is an HJC AC-12 with a snug, perfect fit. It has the best wind bucking characteristics of anything that I've tried. It's well vented, comfortable, quiet, and relatively inexpensive. A bonus is that HJC's red is a dead match for the Anniversary red color of the GT.

A helmet is properly fitted when it fits snugly with no pressure or hot spots. When you try to move the helmet around on your head, you should be able to feel your skin and scalp moving with it. If the helmet is just sliding around, it is too loose.

Your jacket should fit well, too, with no looseness. Ducati's Summer jacket is actually made by Dainese, and fits like a dream.

With the wind no longer tugging at your appearel, you'll immediately notice an improved experience. With no tugging and flapping, the wind becomes merely a gentle pressure. You just lean slightly into it, automatically assuming the optimum riding position that Ducati designed into the GT.

Ducati's windshield and various fly screens mount to the front forks, not the frame. Ducati limits speed to just over 80 MPH with one of these fitted. At higher speeds, you risk fork wobble and tank slapping.
 

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Also, the GT's engine power and smoothness happens at RPMs above 4,000. I'm not sure of the effect of the 14t sprocket, but my GT would have little power in 5th gear and 60 MPH. RPMs would be too low. I spin the s**t out of the engine, seldom using sixth gear. I find the power band, and use it.
 

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Discussion Starter · #11 ·
Thanks TSMGGUY,

As for apparel, I wear a very snug fitting Mesh/Tex jacket, full gauntlets, tsnug fitting pants, and Sidi B2 Boots. I have no flapping, or drag from my neck down (I learned that the hard way going on the highway with a too big jacket...flap....flap...flap).

I think you guys are all right my helmet needs to be tighter.

As for my bikes performance, I am a t a lose. It does not feel like a bike with 82 HP and 65 FTP Torque. It seems to pull ok from a stop, but nothing that knocks my socks off. Like I said before my little to me Ninja 650R seems to be as fast if not faster.

Maybe I am running on 1 cylinder?
 

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Discussion Starter · #12 ·
How far are you pulling the engine? If I am riding aggressively I will pull it up to 7,500 RPM, but its still feels like a hamster in a wheel, lots of spin up, but not doing much. I don't know, to me my bike does not impress me with its power at all, but rather I am in love with its looks, and feel.

If it turns out that my bike does not have a performance issue, I will not be doing any performance mods as I feel it would be worthless to spend thousands of dollars to achieve such little HP gains that I will hardly notice. I will just keep it the way it is and enjoy her retro looks.

Its funny I hear some of you guys talking about power wheelies and such; I could not power wheelie this thing unless I hit bume and yanked the the front wheel up myself.
 

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I gotta agree with tsmgguy, that something doesn't seem right here. Especially this statement:

If I am riding aggressively I will pull it up to 7,500 RPM, but its still feels like a hamster in a wheel, lots of spin up, but not doing much.
My GT is stock, and acceleration isn't a problem at all. It pulls nicely and somewhat aggressively from a stop. I tend to ride with all sorts of bikes and have no problem keeping up with most of them (save for maybe some sport bikes, like a 'busa :p). Getting it 100+ MPH is no problem for it, and generally I'm not in 5th gear until I hit mid-70's MPH. I won't think of 6th unless I'm 85+ and planning on staying there for a while.

I hope you get it figured out though - the GT should be more than just eye candy IMO.
 

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Discussion Starter · #14 ·
I am going to do some dyno testing. I wanted to do this to get a baseline to know what the bike is doing stock. Then I was going to dyno test after every performance mod to see what the results are. But now I want to get on the dyno to see if my is actually performing to what it should be out of the crate.
 

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Its funny I hear some of you guys talking about power wheelies and such; I could not power wheelie this thing unless I hit bume and yanked the the front wheel up myself.
Yeah, something about this isn't right. Stock this bike has enough torque to easily lift the front wheel. Between that and your description of your riding (spinning up to 7500k before shifting, which is reasonable, and you're in 5th gear at 60mph), I would guess your clutch is not delivering the power to your wheels. Have you checked to see that you have a bit of free play in your clutch cable? When you're riding and you crank back on the throttle relatively fast, does the engine rev or does the bike lunge forward? If the engine can rev quickly in gear without a quick corresponding increase in speed at the wheels, your clutch (or cable adjustment, if it's holding the clutch open) is not doing its job.

Alex
 

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Discussion Starter · #16 ·
I will check the clutch but I have not noticed any slipping with the clutch. However, once in awhile the bike will slip out of gear. On Sunday, down shifting from 5th to 4th, I some how got the bike in a neutral state, in between gears, which I thought was extremely weird, and scared the crap out of me when all of a sudden the bike just revved and did not go anywhere (for a split second I thought "what if this thing kicks into gear and locks up the wheel!" so quickly pulled the clutch in and shifted up into gear.)

Also every once in awhile I will go from 1st to 2nd, punch it and it clicks into neutral.
 

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80 mph is pretty much the place where you begin to feel the blast. That's why 150hp nakeds are kinda silly. I look at it a a speed linit restrictor to keep me from going to jail. The GT is very calm at 80+ and tracks well all the way up to 135.
 

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Dude,

Something is wrong with your bike. It is not your weight. I weigh more than you (295 with gear--not a typo). It is not your broad shoulders--I have them too (I wear a size 56 suit and need them custom made for my shoulders). I can power wheelie at will in first gear. I go 100 mph routinely on the freeway with no problem.

Barfer
 

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Discussion Starter · #19 ·
How much are you guys pulling the bike RPM wise? Is over 8000 RPM point less or is that peak power and then a sudden drop?

Thanks
 
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