5th gen vibration

[VFROZ]

My 2001 has had a vibration that starts around 6750rpm ever since I bought it. Hits its worst around 7500rpm and then tapers off but never goes away.

It is not stock.

It has coil on plugs, K&N air filter, no snorkel, no pair valves, Staintune muffler with no baffle, and Delkevic headers with no cat or O2 sensors.

I bought it with 60000km on it four years ago, it recently turned over 100000km but it has always been the same.

It got worse since I got rid of the cat.

I've rebuilt the FI system about 10000km ago and had the injectors cleaned and flowed. All within 1%.

I'm about to do the shims again as they are due, and I keep a good eye on my starter valve adjustment, this does make a bit of a difference if they are out but I canot get rid of the vibrations.

The FI system has been removed before from what I could see, but I don't know why.

Could it be that the butterflies are out?

Can you even get that checked?

Shoping for a PCIII at the moment, but that is not going to fix it.

Any ideas will be appreciated.

[GleninAus]

Hard to pick a direct solution for your reasonably well modded  setup but something a simple I do for a test when I get a bike with Vibe issues is run a clean tank different octane fuel.  If the Vibe changes then maybe the PCIII can help.

Have the O2 sensors been properly bypassed?

 

2 hours ago, VFROZ said:

Could it be that the butterflies are out?

If the vibe happens at full throttle, nope.

[Terry]

My 98 is pretty similar from a vibration perspective and always has been. I bought it stock with 76000km, now has 98000. Doesn't bother me at all.

[VFROZ]

I never thought to pay attention to see if it's the same at full throttle openings, and it make sense that if it does, it's not the butterflies. 

I did install resistors to the O2 delete. 

It never bothered me before, but it has definitely got worse since decat. 

I will also mention it's not road speed related and it is identical in all gears. 

Ive recently rebuilt my rear hub and front wheel bearings. 

Sprockets and chain are top notch and spot on but with a 45T rear sprocket. 

Suspension and brakes have all been upgraded. 

 

[maxredline]

Have you riden a stock Viffer to compare yours too? I have found mine has always vibrated to the point that if I could not hear I would still know when to change gears by the vibration level due to the layout/timing of the engine.

[VFROZ]

I haven't ridden another 5th.

And as you say, I don't need to look at the tacho.

I've owned a VFR750F, and a VF1000, I remember both being smoother.

I tried wide open throttle, and vibration is the same, so not the butterflies.

I wll be doing some major maintenance this Xmas, but I don't think it will make much difference.

I've got some heavier bar ends coming, and I'm going to try extra weights on the pegs to see if it helps.

It has always vibrated since I got it, but it is worse since decat.

[BCmcrider]

I was chasing a vibration for quite a while till I finally started balancing my own wheels.  For a long time, I thought it was an engine vibration.  Might be something to try.  The machine balance from the tire shop was not up to my butt test.

[slowbird]

I think my 5th gen is the same.

I would worry it was a tire or head bearing but when I pull in the clutch it smooths out. Definitely engine related.

[BCmcrider]

On 3/5/2017 at 2:50 PM, slowbird said:

I think my 5th gen is the same.

I would worry it was a tire or head bearing but when I pull in the clutch it smooths out. Definitely engine related.

 

I did the same thing with the same result and talked to others here as well as tried their bikes for comparison.  The clincher was when the BMW dealer put 3 Oz on my back wheel.  That particular case was an anomaly as I think there was something wrong with their mcn but that's when I started balancing my own and noticed a big improvement.  I never think about balance anymore.  The other thing to try is to tighten up your rear shock damping as I also noted that that caused a jumping on other than perfect roads.  

[MaxSwell]

I have a clue for you VFROZ. I've had five fifth gens and every one needed new steering head bearings. One before 30,000 mi. Recommend replacement with All Balls tapered roller bearings. It's easy to check. While on the center stand, have someone hold down the rear end or put sufficient weight on the seat (a couple of concrete blocks worked for me). With the front wheel off the ground see if there is ANY free play in any direction. Free play = bad bearings.

Honda used some wimpy ball bearings in these fifth gens.

I hope this solves everyone's vibrations.

Let us know what you find.

[VFROZ]

There is not much on my bike that is standard MaxSwell. 

From memory I have VTR1000, GSXR750, CBR954, CBR929, CBR250, CBR600, R1 and some custom parts in there.

There is not much that hasn't been replaced, and I can tell the difference between wheel, bearing or engine vibrations. 

On my bike it was starter valves, you can easily tell as it happens at the same engine speed regardless of gear or road speed. 

It was more noticable when I removed the cat, and while not terrible, it annoyed the crap out of me as I'm pedantic when it comes to my bike. 

It is much better now and I'm happy. 

I now have everything sorted and can concentrate on coming up with some new mods. 

 

[boOZZIE]

3 hours ago, VFROZ said:

There is not much on my bike that is standard MaxSwell. 

From memory I have VTR1000, GSXR750, CBR954, CBR929, CBR250, CBR600, R1 and some custom parts in there.

There is not much that hasn't been replaced, and I can tell the difference between wheel, bearing or engine vibrations. 

On my bike it was starter valves, you can easily tell as it happens at the same engine speed regardless of gear or road speed. 

It was more noticable when I removed the cat, and while not terrible, it annoyed the crap out of me as I'm pedantic when it comes to my bike. 

It is much better now and I'm happy. 

I now have everything sorted and can concentrate on coming up with some new mods. 

 

Could you elaborate on the differences that you get from the vibrations of :-

-Front wheel 

-rear wheel

-front wheel bearing 

-rear wheel bearing

-steering head bearings 

-engine 

[VFROZ]

Front wheel bearings can be felt on both bars, and it will be road speed specific. 

It will feel the same no matter what gear you're in. Easy to check, lift front wheel off ground and rotate, you will hear or feel a rough spot as you rotate wheel. 

 

Rear wheel bearings might not be felt from all the chain clatter, but when mine started to go I could feel the rear stepping out slightly when I transitioned from trail brake to hard throttle after apex when pushing it. 

 

Steering head will also also be felt when pushing the front end as it won't hold a line when pushed hard. I've never had a vibration from steering head bearings, just lose feel. 

Again easy to check, lift front wheel of ground and check for notchiness when going left right, or play on triple clamps when pushing front wheel front to back. 

 

Wheel balance will vibrate the whole bike, and again will be speed specific, this is a bit harder to self check. 

You can normally feel front out, rear is much harder to feel. 

 

If its its engine vibration, it will happen across a rev range, and is mostly felt on front right bar and left footpeg. 

It will be worse at heavy engine loads and will happen at the same revs no matter what gear you're in. 

On mine it started at 6500rpm, got worse at 7000rpm and kept going all the way to red line 

[boOZZIE]

2 hours ago, VFROZ said:

Front wheel bearings can be felt on both bars, and it will be road speed specific. 

It will feel the same no matter what gear you're in. Easy to check, lift front wheel off ground and rotate, you will hear or feel a rough spot as you rotate wheel. 

 

Rear wheel bearings might not be felt from all the chain clatter, but when mine started to go I could feel the rear stepping out slightly when I transitioned from trail brake to hard throttle after apex when pushing it. 

 

Steering head will also also be felt when pushing the front end as it won't hold a line when pushed hard. I've never had a vibration from steering head bearings, just lose feel. 

Again easy to check, lift front wheel of ground and check for notchiness when going left right, or play on triple clamps when pushing front wheel front to back. 

 

Wheel balance will vibrate the whole bike, and again will be speed specific, this is a bit harder to self check. 

You can normally feel front out, rear is much harder to feel. 

 

If its its engine vibration, it will happen across a rev range, and is mostly felt on front right bar and left footpeg. 

It will be worse at heavy engine loads and will happen at the same revs no matter what gear you're in. 

On mine it started at 6500rpm, got worse at 7000rpm and kept going all the way to red line 

great info.

Thank you ?

[MaxSwell]

I forgot about the notchy feel when the front wheel is off the ground. Thanks for the reminder. That is how I was taught to test it.

 

It did seem to me a cupped front tire felt the same, symptom-wise, as the worn steering head bearings.

[GreginDenver]

The VFR's V4 engine is just 1/2 of a flat-plane crankshaft V8 engine.  Our flat-plane V4 has the same package of advantages-disadvantages as the flat-plane V8, you can google search and learn about them.  The flat-plane V8 engine has more vibration than a cross-plane V8, specifically a "second order" vibration (sometimes described as a "rocking" type of engine vibration) that is caused by the alternating-bank firing order (in the case of our V4 there are two occurrences of this event every 720 degrees of engine rotation, the firing of #3 and then #2 cylinders and the firing of #4 then #1 cylinders, one just after the other in separate cylinder banks.  The flat-plane V8 has eight of these events per 720 degrees.  This has the same effect in either engine).

 

The performance advantages of a flat-plane crankshaft in a 90 degree V engine are big enough that manufacturers like Ferrari are willing to accept the downside that comes with the package.  They do things to minimize the downside, like biasing the cylinder's bore & stroke toward the "oversquare" end of the spectrum (Honda went with 72 X 48mm in the VFR800). 

 

So if this is something that all VFRs share, why do some riders seem to feel it more than others?  I've seen this sort of phenomena before, on other motorcycles (inline-4 cylinder engines produce some primary and secondary vibration).  I've always imagined the bike functioning as a big tuning fork (the combination of engine, frame, handlebars, handlebar end-weights, foot-pegs, and etc.) and from the factory our VFR800 was tuned to (as much as possible) resonate out-of-phase (i.e. to passively cancel out) the V4 engine's inherent secondary-order vibration.  All it takes is changing a few items in that "whole-bike" equation and you can accidentally end up with a big tuning fork that resonates with the engine's secondary-order vibration (amplifying it) instead of passively against it (and feeding it directly into your hands on the handlebar grips).  

 

Just saying that in the process of "personalization" of your VFR800 you may induce some (minor) unintended negative consequences along with the positive changes that you had in mind.

[Mohawk]

^^^^^^^^^ What he said. They all do it, some feel it more & that could be down to tolerance variance in the parts build, some bikes have close to blue print spec & some are right at the tolerance limits which may be why some feel more vibration than others.