Vibe

[kwallace21]

I have an 1150 GSA 04 and at a steady throttle at motorway speed I get a slight rythmic type vibe. Not excessive but just wondered if it's a common thing. Just had it expertly serviced, valves, end float, TB balance etc. Engine is running smoother than it ever has been and feels great. wonder if I am now noticing this rythmic vibe/ surge now the engine is so well set up.
Wheel bearings are all tickety boo however I am on tourances that are at least half worn. Any ideas. It doesn't feel or sound worrying but I'm just curious. I suspect tyres or minor fuel injector surge. Oh, gearbox and diff oil changed. all nice and clean with no bits in any of it!

cheers
kev

 

[davegs]

Possibly tyres coast down a hill with the engine off see if it goes.

 

[kwallace21]

Doesn't seem to do it when I shut the throttle off or when I am accelerating so I suspect it is the engine surging ever so slightly on a steady throttle. Not enough to feel it rocking back and forwards but just enough to feel the vibes changing slightly.
With only 15k on the clock I doubt whether it is connected to the shaft or gearbox.
I shall ignore it and enjoy my Europe trip at the end of the month!
Cant bloody wait!!!!!

 

[Rob Farmer]

is it a twin spark? if it is then maybe one of your coil packs have given up the ghost.

 

[kwallace21]

Hi Rob,
yes it is a twin spark but I'm pretty sure the coil packs are fine. It actually runs quite smooth and the surging is unnoticeable except for the minor vibes.
Had the main plugs out at the service and they were both very clean and perfect colour. If one of the coils was breaking down i'm sure the symptoms would be more obvious and it would run like a pig.

cheers
kev

 

[Stewart H]

I replaced my rear Tourance this week,there is a noticeable change in feel with a fresh one on there.

Stewart

 

[kwallace21]

I know what you mean. It is surprising how different it feels with new tyres. I can feel a definite vibe off the half worn front Tourance on slow turns especially. Both the front and back have probably 3 to 4 k left so I'm reluctant to change them at the moment just to do 2500 miles on Euro motorways. Alpine roads should be fun though!

 

[GADGET]

Have you checked for any movement on the rear wheel, was thinkng of the pivot bearing.

 

[kwallace21]

Yes, I have had a good pull of the rear wheel etc and have no sideways play in either the wheel or swing arm etc. All nice and tight.
Almost certain its a slight variation in the fuel injection as it is unable to stay at an exact level on a steady throttle. Barely noticable though. My car probably does the same thing but the weight of the car would mask the feeling.

cheers

kev

 

[(RIP) Yamaha1]

Kev - have look at my recent posting at the top of this section - Steptoe's Final Drive Bearing checking sticky - sounds very much like I noticed on my 1100.

Mike

 

[kwallace21]

Thanks for that Mike.
I could get a mechanic to open it up and inspect it but The fact that the bike has had a fairly easy life with only 15k on the clock makes me think it's probably not worth it. Most folk say that there isn't any warning vibes or anything when these things are on their way out. It is only slightly vibey on a very smooth steady throttle. Not there at all even under very gentle accelleration.
I think I'm just being paranoid. Not there in corners either.
I think I'll ride and enjoy!

 

[kwallace21]

Mike, I forgot to ask. What mileage was on your 1100 when the bearing was worn/knackered.

cheers
Kev

 

[(RIP) Yamaha1]

Hi Kev - those symptons DO sound exactly like mine - but mine has done 40k - does seem too soon for yours to be going!!

Mike

 

[kwallace21]

Cheers Mike.
I agree, 40k maybe but at 15k unlikely.
I took it out last night and it felt brilliant (Ooh Err!)
Only felt those slight vibes in a high gear at around 30mph. Felt perfect at all other speeds even on a steady throttle on motorway. I think I read too many horror stories on this site. If I read a medical book I would probably think I was dying.

thanks for everyones advice.

kev

 

[roddy]

Kev, have you got the adventure crash bars ?, I had a crash bar mount crack, the one under the tank RHS and it gave odd vibes at certain revs, maybe worth a look ?

 

[kwallace21]

Hi Roddy,
no, I have hepco and becker bars fitted and they are all tght. I'm sure it is minor surging. can feel it through the bars slightly but not through my arse or feet so I doubt whether it is from the back end. ( As the bishop said to the actress!)

cheers