Vibrations

[Ajeman]

Afternoon All,

Due to the sunshine I had a lovely ride out to the seaside yesterday (160 Mile round trip) and although enjoyable my overall feeling was somewhat dampened by having numb fingers and toes due to the vibration.

I hadn't really noticed it too much before due to only doing short-ish trips, but a day out really made me notice that it's not something that should be there, and is affecting my enjoyment of the bike as a result.

I have read up a bit on vibration issues and put a list of the most common issues I've found below, what I'm wondering is which order should I look at them. I don't want to start replacing parts just to see if it cures it, I would rather test things first.

1) Wheel balancing
2) Balance shaft alignment/setting
3) CCT
4) Frame bolt torque
5) Exhaust bolt Torque

Anything else I should look at? and what should I look at first?

It's on an 06 model and has been looked after by a dealer.

I will be "test riding" it later to see if the vibration peaks at certain revs/disappears when clutch is pulled/present when stationary and will update.

Regards,

Ajeman

 

[lee j]

Take it that you are referring to a b/bird??!! Year you say is '06 but what is mileage?

Yes - add to your list:-
Chain condition (stretched or worn)
Sprocket conditions
Rear wheel drive cush rubbers/bearings.
Chain adjustment (too tight is more of a problem than a little slack).

Found my b/bird (also the previous one a VFR) were happier with slightly slack chains. Normal on the b/bird is 30-35mm slack on the centre stand, but, if you have a 6mm shock spacer added then increase the slack to 40-45 on the centre stand. Err on the top mm.

Unfortunately, just because it has been "looked after by a dealer" does not mean to say that all is correct. (as has been commented on several occassions recently on both this and the vfr forum)

Lee

 

[noobie]

Both pretty much have covered the possibles.Had it been just the bars I would have added have the bar weights been changed? I always work through the cheapest/easyiest fixes first.

Something I would add is tyre pressures, make sure both are running at 42psi cold.

 

[DEG5Y]

Standard pipes?

The weight of the standard pipes help to dampen vibration.

 

[Jaws MC Gary]

Would suggest getting your tyres rebalanced as you may have lost a balance weight which would cause vibration, along with uneven tyre wear?

Just a thought

 

[Ajeman]

Hi all,

Thanks for the responses. On the ride home I pulled the clutch in and the vibration disappeared, so I'm thinking the wheels/tyres, and that are OK? Tyres are new and checked pressure yesterday so all good. I have added bar risers but vibration was present before this.

So looking at engine issues, do I start with balance shafts? (Although this is quite involved as fairing needs to come off) will check chain when I get home but think this is OK.

Regards,

Ajeman

 

[Centaur]

Having been through this recently with Petros in Greece.

1 How many miles since a new cct was fitted? That would be the most likely option. The engine sounds like a bag of nails at 3/4000 rpm.

2 Balancer shafts. http://www.bikersoracle.com/blackbird/forum/showthread.php?t=73308

3 Engine mounting bolts need retorquing. See above link.

If it goes when you pull in the clutch and let the revs drop then it will be one of those IMHO.

 

[Dickiebird]

I reset my balancer shafts recently and was surprised by the amount of difference it made. It was immediately noticable. it's not that complicated at all. In fact it can be more fiddly replacing the fairing panel (RHS). 25-30 min.job, and if it makes no difference, at least you've ruled it out !@tu*