pulling hair and screaming over vibration!

Ok so I have a vibration in the front wheel (posted a while back about it.) Since then I've had it to the local honda dealer where the bike was purchased. First I replaced the sprockets and chain. I was also due for a set of tires so I put Michelin pilot road 2's on. Vibration....still there. I had the mechanic go over the bike head to toe. He checked the rear bearings, front wheel bearings, steering head bearings, brake rotors, wheel balance, rim with calipers for damage and still have vib around 140 km/hr. I tried dyna beads and still vibration. He said there is nothing else he can do at their shop because of their limited resources. He suggested getting the front wheel high speed balanced somewhere. I'm wondering if I can interchange the front wheel with another bike and see if the problem is in the actual wheel. Does anyone know if there are any other hondas that would bolt up to the vfr? Any other suggestions or recommendations I'M ALL EARS at this point. HELPPPPPPP! LOL!

 

I don't have any specific answers, but you mention the Dyna Beads. I use them myself, but there are others that complain of the dyna beads causing vibration at higher speeds. Not sure about the 140 km (90mph?). I usually have some vibration at that speed using the dyna beads, but I seldom reach that speed, so I never notice anything. If you had the tires balanced prior to the beads, then you're probably going to need to try another wheel (front I guess). I'm assuming that the vibration occurs on various roads at ~ the same speed.

 

Yeah, doesn't matter what kind of road, always get the vibration at the same speed. Bike is smooth Taking it to another bike shop this weekend for high speed balancing. Still trying to find out if front tire off another bike will bolt up. I have a close friend with a CBR600 F4. Gonna do some measuring I guess.

 

It does sound like you're covering all the bases. If I understand, you had the bike, and the vibration. You changed tires, and still the vibration (in addition to all the other things that were checked).

I know its a stretch, but would you're dealing be willing to mount another tire up from just for comparison sake? As unlikely as it may be, maybe you changed out your old bad tires with a "bad" new tire.

 

Did you verify that the suspension is setup properly for you? I get a vibration at higher speeds (the closer I get to 100 the worse it feels). It's nothing dangerous but it's noticeable. I'm fairly certain I need to work on the suspension a touch as it's definitely not setup for me. I got this great advice here but can't attribute it to a particular source because frankly - i forget! It's a great place to look when all of the obvious issues are covered.

 

I'd check your chain tension as well. Perhaps it is your tires not inflated to the correct psi. Don't really know what else to say buddy.

 

Jerk both wheels and have them spin balanced. If you just bring the bike in they will stick you for a labor charge for the mounting and dismounting plus the charge for the balancing.

You might want to take a close look at your front wheel to see if there is any evidence of a weight that went bye-bye.

Could be a bad headstock bearing too. Some had plastic races..

We will now hear from those who built thier own balancing rigs from Tinkertoys, Legos or scrap lumber and drywall screws.

 

Same problem, same speed. AFTER fitting the exact same tyre. Rebalance and rechecking bearings at 24,000 service. Did not have this vibration previously with the Dunlop that came on the bike when I bought it. I'm currently running the front at 32psi to try and "soften" the vibration. Only shakes unpleasantly at above all legal speed limits down here, so is a good reminder to back off a bit. For the time being at least. . . .

 

You can take a dial indicator in a mount and check the run out of the wheel up and down (radial) plus side to side (axial). Just wondering if the rim got a very slight bend at the lip area when the tire was changed. It may be out like .015" and it won't be seen by the naked eye. The book says max .008" run out for both. If the wheel vs just lip is bent then the indicator would read .004" for a total of .008" max tolerance.

Check all the engine to frame bolts for proper torque.

 

This might sound silly, but have you tried pulling in the clutch at the vibration speed to make sure that it's not engine/transmission related? The only other thing that comes to mind is a new tire that is out of round. I had one on my ex-07 (BT-021) that was smooth until about 90 MPH. I only found the problem when I had the bike on the centerstand and in gear to warm up the chain a bit before lubing it. It was out of round by about 1/4". Technically, it had a "low spot" that was about 8-10" in length, the lowest point being 1/4".

 

A good case for dynamic balancing. Static balancing carefully done by someone with experience is fine. Many here have probably done static balancing on spoke wheels using a lenghth of pipe on uprights, a dinner fork and a spoke wrench. VFRs ain't the fastest bikes on the planet except for a few who are owned by some dudes here that IMO have calculexia.

I'm thinking your dealer does not have the equipment for a dynamic AKA a spin balance if indeed the problem is the wheels or tires. Your Michelin rep may be of some assistance. If you are riding your bike and it's shaking its head, I am too. Don't become a statistic or one of those crash vids..