New Hayabusa Gen3 Vibrations

[Jurassic]

Since this is my first post here: Hello Everyone!



I got my first ever Busa this year, a brand new 2023 model from the dealer. The bike is great overall, yet it has this strange vibration kicking in after reaching roughly 120mph, then it starts to diminish at about 160 mph. I know there have already been a few threads about vibrations across all the generations. However this one seems strange because the bike only has a few thousand miles on it and had that since new (well, technically since the first time I have reached that speed after the break in period). I have just replaced the factory tires (rear was done anyway and I replaced the front just in case), freshly balanced - same thing.

I don't believe it is wheel related though anyway, since the vibration changes completely depending on the gear - 6th is the worst, 5th better, 4th is actually not that bad. Funny thing is that I talked to the dealer about it, but they claimed it sounds normal and they gave me a another bike for a a test ride (their demo, so fresh as well) but that didn't help - it also had the same exact thing. On the other hand, my ZX10R gen5 is extremely smooth at those speeds (as well as at any other - just to make a point I'm not being overly sensitive about vibrations), as smooth as I would expect the Busa to be... However, here comes the interesting part - the dealer did admit that there are several cases alike reported to Suzuki HQ. But only that, no recall nor any other reaction from Suzuki itself.

Anyway, long story short:

Is it possible that the engine mountings were incorrectly torqued from the factory? Or maybe something can be improved through adjusting the balancing shaft? Don't know, just brainstorming here. Anyone with gen 3 had similar experience, where the wheels were (at least most likely) not the issue? Especially with a new bike? Any other ideas what this might be?

The vibration is not excessive, it is somewhat bearable, yet it's far from comfortable and far from what I expected the new Hayabusa to be. Especially since most of the users report the ride being silky smooth throughout the speed range. Any advice is very appreciated.

BR,
J.

 

[Bumblebee]

Welcome.......

Although I can't help you with your problem as I don't have a Gen 3, the sad part is it could be almost anything....

Maybe the harmonic balancer is adjusted slightly out of spec....as described by our very own @c10

I'd imagine the Gen 3 is the same as the gen 2 as they share engines...

 

[sixpack577]

Welcome.......

Although I can't help you with your problem as I don't have a Gen 3, the sad part is it could be almost anything....

Maybe the harmonic balancer is adjusted slightly out of spec....as described by our very own @c10

I'd imagine the Gen 3 is the same as the gen 2 as they share engines...

Try this first^
Let us know if it helps.
The Gen3's seem to unfortunately have new problems regulary now, but they should be very smooth all the way to top speed.
Obviously the demo bike has the same problem...but shouldn't either.
I would be curious to know how close the 2 bikes were built to each other, as in using the same batches of different parts coming down the assembly line.
I would check it's VIN# against yours to see, not that it will solve anything.

welcome to the org

 

[wellcraft]

Where are you feeling the vibrations? Handlebars, foot pegs, seat? You might not be able to solve your vibration problem but it may be possible to mitigate the effects with heavier bar end weights, after market foot pegs and a seat pad. My 2022 BMW S1XR has a little vibration at certain RPMS so I added heavier bar end weights which helped reduce felt vibrations.

 

[VNE]

Seeing it's your first ever Busa, have you ridden any others or older models? Their fuel maps arent that tidy tbh, and there are dead spots in the RPM range that cause vibration that maybe a new Busa rider may notice or not like. Nothing crazy, but still noticeable. I've seen the fuel map graph on a computer screen and they're not very linear or clean at different RPM, gear and speeds.
Go to a different dealership and test ride more demo's.

But in all honesty, find a long time Busa rider near you to test ride it and make their own judgement and they'll know by feel if there's certainly something mechanically wrong with the bike. If there is, it's usually something tightened incorrectly if the vibrations are kicking in and out at different frequencies due to harmonics caused by a badly assembled bike or faulty part. Good luck and hope it goes well. I know I wouldn't sleep until I found it. Imagine if it was an airplane...

EDIT: Check the lead weight on the wheel rim is still there. Sometimes they fall off, sending it out of balance.

 

[sixpack577]

Seeing it's your first ever Busa, have you ridden any others or older models? Their fuel maps arent that tidy tbh, and there are dead spots in the RPM range that cause vibration that maybe a new Busa rider may notice or not like. Nothing crazy, but still noticeable. I've seen the fuel map graph on a computer screen and they're not very linear or clean at different RPM, gear and speeds.
Go to a different dealership and test ride more demo's.

But in all honesty, find a long time Busa rider near you to test ride it and make their own judgement and they'll know by feel if there's certainly something mechanically wrong with the bike. If there is, it's usually something tightened incorrectly if the vibrations are kicking in and out at different frequencies due to harmonics caused by a badly assembled bike or faulty part. Good luck and hope it goes well. I know I wouldn't sleep until I found it. Imagine if it was an airplane...

EDIT: Check the lead weight on the wheel rim is still there. Sometimes they fall off, sending it out of balance.

This is a good point, because as smooth as the Busa is, they do have a buzzy spot in the rpms at highway cruising speeds, but that does go away as the rpms climb.

 

[Jurassic]

Thank you guys for all responses.

Balancing shaft is on the top of my list to check before next season. I  feel the vibration on handle bars for sure. There could also be slight on footpegs but I went with lowered aftermarket ones that are lacking the rubbers which might be causing it, pegs are not excessive at all though. My  hands do not go numb either, yet the windscreen and mirrors shake quite a bit. I was also thinking about the bar ends. Which ones would you  recommend for that particular issue? Has anyone tried birdshot? Not sure  if it was all that noticable on the seat.

I havent ridden any other generations. The engine was mapped due to switch to R77s and in hope the tune will smooth things out. As  long as it did help of course to smooth the engine after partial decat when switching the end cans, it didn't improve  that particular vibration.

The balancing of the wheels or missing weights should not be the issue,  as it was already done and didn't improve anything.

This is a good point, because as smooth as the Busa is, they do have a buzzy spot in the rpms at highway cruising speeds, but that does go away as the rpms climb.

What  specific  rpms do you have in mind? I'd say it's worst somewhere around 6-7k rpms,  then the higher it goes the more  it improves. Highway cruising is perfect here, it's when it gets to highway  smashing when it kicks in. At least until I go into highway terror mode when it starts to let  go, lol.

It is a bit  of a mind f... because it happens only  within certain rpms AND only  at certain speed ranges. Don't get it. Anyway, will come back with some feedback if I  manage to resolve this.

All best,
J.

 

[sixpack577]

Thank you guys for all responses.

Balancing shaft is on the top of my list to check before next season. I  feel the vibration on handle bars for sure. There could also be slight on footpegs but I went with lowered aftermarket ones that are lacking the rubbers which might be causing it, pegs are not excessive at all though. My  hands do not go numb either, yet the windscreen and mirrors shake quite a bit. I was also thinking about the bar ends. Which ones would you  recommend for that particular issue? Has anyone tried birdshot? Not sure  if it was all that noticable on the seat.

I havent ridden any other generations. The engine was mapped due to switch to R77s and in hope the tune will smooth things out. As  long as it did help of course to smooth the engine after partial decat when switching the end cans, it didn't improve  that particular vibration.

The balancing of the wheels or missing weights should not be the issue,  as it was already done and didn't improve anything.


What  specific  rpms do you have in mind? I'd say it's worst somewhere around 6-7k rpms,  then the higher it goes the more  it improves. Highway cruising is perfect here, it's when it gets to highway  smashing when it kicks in. At least until I go into highway terror mode when it starts to let  go, lol.

It is a bit  of a mind f... because it happens only  within certain rpms AND only  at certain speed ranges. Don't get it. Anyway, will come back with some feedback if I  manage to resolve this.

All best,
J.

Busa vibrations are common at 60-70mph/highway cruising speeds.
It's noticeable in the pegs too, especially without rubber on them.
The Busa already has heavy bar-end weights compared to other bikes, and I havn't tried anything heavier.
Other than the balance-shaft adjustment, it sounds normal to me after hearing more details.
I personally prefer Pro-Grip #761 grips, a contoured shape medium gel, not squishy and not firm.
I have used them on all my bikes for mang years, and they help with comfort and vibrations.
They may or may not be right for you personally, but a different grip may help.
Windshields are also a personal preference, and I like stock.
But, many people prefer other styles, depending on height, body position and size, and helmet, a different windshield is not going to help with engine vibration, but can calm some of the wind around you, and improve the ride.
Also check your suspension sag, as if it is set too firm, you will have a rough ride, and it can cause vibrations and make engine vibrations more noticeable.
The balance shaft adjustment is also pretty simple, and you should be able to do it without completely removing the left fairing, and just swinging out the bottom of it instead.
The balancer is usually set correctly at the factory, and most bikes with them don't need adjusted...but some do, so eliminate that as a problem before doing anything else.
I would also pull all the fairings and check every fastener and engine mounting bolts, as something loose can make normal vibrations much worse.
The Gen3 has alot of issues too, so something left loose at the factory would not be a suprise...even on multiple bikes.
That's why I was curious if the dealer with the other Gen3 with the same vibrations came down the assembly line close to yours, if the same batch of bikes remained together from production to sales, and a bad setting, or loose or defective part could plauge several in a row without being caught, until the customer noticed.
Let us know what you find out, and good luck with it.

 

[groran1000]

It looks like it's in the RPM zone of vibration. I'm not sure what rpm it's at 120mph but it's probably close to the 4-5k range, if so, it's normal. Check your rpm at those speeds.

 

[Bumblebee]

I really noticed the buzz with my Hayabusa.....it's very similar to my old '85 GSXR (s).....

Sometimes my hand fall asleep if I cruise at around 4-4500 rpm.....

 

[chrisso]

Mine's silk compared to my old S1000RR, and for that matter, my current L6 GSXR1000

 

[Duro5341]

Ever Suzuki 4cyl I have ever owned (1982 GS750E, 2004 Katana 750, 2024 Hayabusa) has ALWAYS had a vibration in the bars between 4200-4500RPM. Your speed at this time will depend on gearing, but it always seems to land in the spot your cruising in on the highway some how.

This just seems to be the natural resonance of the engine itself, and the point in which you can feel the most vibrations.

Many before are right, jetting and mapping on Suzuki's are never perfect and you get dead spots through the throttle range.
On the older Carb'd bike we could fix this with a proper jet kit, and remove the emissions crap..............but now with computers it all comes down to the tuner, and how long they spend perfecting the map and removing the PAIR and cats to get it running perfectly.

Out of the box the bike is as silky smooth as any other manufacture, even though NOT perfect.
I have found Kawasaki to be the worst with their peaky powerband.
Kawasaki seem to tune for peak power to get the numbers they want and forget about the rest

Just my 2 cents
Cameron

 

[Jurassic]

Once again, thanks for the replies.

Powerband was smooth when measured on the dyno, both before and after (can't find the chart at the moment). I don't think my bike was produced closely to the demo as mine is 2023 (although bought new this year) and demo was 2024.

The grips are something to consider, yet it's also about the rest of the front that impacts the ride.

The issue is with higher speeds than cruising 70mph, it is with 120-160mph with 7-8k rpm worst, when in this speed range on 6th gear.

The suspension sag is weird in my case as I was also wondering whether I'm not too heavy for the stock settings (~240lbs with gear). I did the cable tie test in front - all good. However, the rear, which I expected to statically sag more than the recommended 30-40mm, actually did only 20mm or so. I need to get the suspension properly set before the next season anyway and I will see if it helped.

I will come back with some feedback if I will find anything specific.

All best,
J.

 

[Duro5341]

The suspension sag is weird in my case as I was also wondering whether I'm not too heavy for the stock settings (~240lbs with gear). I did the cable tie test in front - all good. However, the rear, which I expected to statically sag more than the recommended 30-40mm, actually did only 20mm or so. I need to get the suspension properly set before the next season anyway and I will see if it helped.

I'm closer to 280+lbs, and I have the front at about 35-40mm with the preload maxed out (out 1/2 turn from lock), and the back sag is around 30-35mm for the street where it should be. The rear shock I didn't touch, but I did bump the compression up in the Front and Rear to their ~3/4 setting, and bumped the rebound up a click or two as the suspension is kinda soft and floaty out of the box.

It transformed the bike, and it's now on rails....................Eventually in the future I'll up rate the springs for my weight, thus allow me to back the compression down a bit but the rebound is perfect no bounce at all.

I'd back the rear shock off a 1/2-1 turn, and play with the compression and rebound........................If the rear shock is to stiff, the back-end will feel twitchy, especially coming on the power out of a turn. You want the back to settle down and be planted coming out of the corner for confidence.

Cameron

 

[sixpack577]

Once again, thanks for the replies.

Powerband was smooth when measured on the dyno, both before and after (can't find the chart at the moment). I don't think my bike was produced closely to the demo as mine is 2023 (although bought new this year) and demo was 2024.

The grips are something to consider, yet it's also about the rest of the front that impacts the ride.

The issue is with higher speeds than cruising 70mph, it is with 120-160mph with 7-8k rpm worst, when in this speed range on 6th gear.

The suspension sag is weird in my case as I was also wondering whether I'm not too heavy for the stock settings (~240lbs with gear). I did the cable tie test in front - all good. However, the rear, which I expected to statically sag more than the recommended 30-40mm, actually did only 20mm or so. I need to get the suspension properly set before the next season anyway and I will see if it helped.

I will come back with some feedback if I will find anything specific.

All best,
J.

At 240 lbs you definately need heavier fork springs for ideal handling, and it is noticeably worth doing.

 

[sixpack577]

And
The front and rear suspension directly effect one another.
If one is good and the other is not, the whole ride will suffer.

 

[Jurassic]

At 240 lbs you definately need heavier fork springs for ideal handling, and it is noticeably worth doing.

I am no expert in suspensions, but in that case how come the forks  are not bottoming out? And this is with stock settings so not only there is a buffer in the suspension travel when riding (I'd say that if anything it's too much of a buffer than too little, its more like 2-3cm, ideally should be 1 I guess) but also in the factory settings that still have some space to increse the preload.

 

[sixpack577]

I am no expert in suspensions, but in that case how come the forks  are not bottoming out? And this is with stock settings so not only there is a buffer in the suspension travel when riding (I'd say that if anything it's too much of a buffer than too little, its more like 2-3cm, ideally should be 1 I guess) but also in the factory settings that still have some space to increse the preload.

..."for IDEAL handling".
They are working, but probably too stiff to function like they should.
Stock fork springs are for 150-190ish lb riders