Engine vibration

[El Thermidor]

Evening all.

I have a query about engine vibration - I think I might have a bit too much. I've had my first 1150GS for a couple of months now, and it runs like a peach up to 75mph, on light throttle. Open it up, or run it at 5000rpm or more, and the engine vibrates badly (well, I think it's bad - buzzy mirrors, bars, tank, pegs, seat). I gave it a full service, just to be on the safe side, but it's still doing it.

Have I bought a dud, or is it easily fixable? Or am I going to get a whole bunch of replies that say "They all do that, sir"? I'm not expecting V12 levels of silkiness, but I would like to get to 30 without white finger...

 

[Baz]

Mine vibrates a small amount but no worse than the VFR I had previously. Not really had much experience with the flat twin, but sounds like maybe an imbalance or something with the fuel mix on one of the pots. I'm sure some one will be along soon to contradict me.

Baz

 

[Gecko]

Valve adjustment and throttle balancing should cure it. Do it yoruself and take the time that B#W dealers don't take and it should be lots better .

 

[Wino]

I've got a 1100 gs and found that it also vibrated at 70-90 mph but was smoother lower down the rev range. Done a full service, oil, filters, plugs and valves and the bike is transformed. This one has 20,000 miles on it and well loosened up, so perhaps yours is of lower mileage. The throttles were good when I checked them on the vacuum gauges so I put the vibes down to being standard but since adjusting the valves it is much better.

 

[ferguscawley]

Yep - I agree completely with what Gecko and Neil just said. Do valves first and then a good throttle synch and you should be fine.

Ferg

 

[littleredrooster]

Yup, mine is now smooth up to 7500rpm when it starts to get a bit 'lumpy'. Do the valve clearances and throttle body-balancing ever so carefully and it is transformed. Takes a bit of time to get right first time out, but well worth it. Engine should be like a turbine up to 5500-6000 at least. Set throttle position sensor to 370-390 mV while your at it - again, makes a difference to smoothness and, particularly, throttle response.

 

[enabb]

Vibes

Am suffering from vibration to, have just about plucked up enough courage to tackle the valves n throttle balancing...
Have read the wisdom of knowledge (several times)...

Anybody got any advice to add for a virgin valve adjuster.....
plus where might I source some decent feeler gauges..


Ta

 

[naked jon]

vibes

C'mon guys, you know what they say about boxer engines - if it stops vibrating, it musta stalled!

 

[(RIP) sherpa]

Originally posted by littleredrooster [/i Set throttle position sensor to 370-390 mV while your at it - again, makes a difference to smoothness and, particularly, throttle response. [/B]

Can you tell us how to do this exactly please?
Sherps

 

[(RIP) sherpa]

Can you tell us how to do this exactly please?
Sherps

Come on guys -I'm only curious!!
leigh must know - although he's gone a bit quiet - must be back at work!!!
Sherps

 

[leigh]

Can you tell us how to do this exactly please?
Sherps

Come on guys -I'm only curious!!
leigh must know - although he's gone a bit quiet - must be back at work!!!
Sherps

yes i do and yes i am!!

 

[Gecko]

Re: Vibes

Am suffering from vibration to, have just about plucked up enough courage to tackle the valves n throttle balancing...
Have read the wisdom of knowledge (several times)...

Anybody got any advice to add for a virgin valve adjuster.....
plus where might I source some decent feeler gauges..


Ta

Enabb
My advice is take plenty of time the first time you attempt it.It's not a half hour job first time so don't try and get finished - you finish when it's done not because time is up. Don't rush and go back and recheck each valve sevaral times until you are certain they are right. Get a comfortable stool to sit on, a regular supply of coffee and stick the radio on and enjoy it. Also take care with torque settings - do not overtighten anything cause it breaks when you do and this is guaranteed to ruin your day .
Second time get's easier and you will surpise yourself how easy it really is - but NEVER rush this job because if you do you will only be rewarded with vibration and rough running and you'll wish you never bothered.

 

[littleredrooster]

OK - TPS setting: Basically, the TPS voltage should be around 370 - 390 mV at tickover. It is not a good idea to do Lentini's Zero=Zero procedure on 1150s - ask Panzer Patrol!!

The wire you need is the red/white one from the TPS (rearmost wire in the block, if I remember correctly). This can be contacted either with a fine pin pushed through the insulation, or by a single strand of a multi-strand wire pushed into the connector block before pushing the two halves of the block together. Make sure that the wire does not contact anything else and cause a short-circuit, 'cos this could blow the Motronic brain. With the ignition on, measure the voltage between this wire and a good earth. It should be 370-390 mV. (Use a digital voltmeter). If the voltage is incorrect, CAREFULLY loosen the TPS clamp screws and rotate the TPS. You will find that a small movement produces a big difference in the voltage reading. When correct, gently nip the screws down and check again. As the TPS is tightened, the voltage changes, so a bit of trial and error is needed until you can tighten the screws fully. After achieving the desired setting, remove fuse 5 in the fusebox, count to 10 and replace the fuse. This powers-down the Motronic. Turn the ignition on, and before doing anything else, turn the throttle from closed to fully-open 3 times. This resets the Motronic. Job done.

Just realised, I could have ridden down to Basingstoke and done the bloody job quicker than I have typed this!!!

Good luck.

P.S. - Valve clearances / throttle body balancing must be correct before doing this.

 

[enabb]

Re: Re: Vibes

Enabb
My advice is take plenty of time the first time you attempt it.It's not a half hour job first time so don't try and get finished - you finish when it's done not because time is up. Don't rush and go back and recheck each valve sevaral times until you are certain they are right. Get a comfortable stool to sit on, a regular supply of coffee and stick the radio on and enjoy it. Also take care with torque settings - do not overtighten anything cause it breaks when you do and this is guaranteed to ruin your day .
Second time get's easier and you will surpise yourself how easy it really is - but NEVER rush this job because if you do you will only be rewarded with vibration and rough running and you'll wish you never bothered.

Thanks for advice

Ordering feeler gauges this week, so might have a go next weekend (unless its wall to wall sunshine)