My 53 plate BMW R1150RT is very harsh on bumpy surface sort of banging (knocking) through the fairing. The suspension moves up and down fine when stationery no leaks etc i have owned it since nov but its the first time i have ridden it do you know of ant problems with these sort of bikes? its done 52,000 miles but has been well looke dafter.

Hmm ... could be all sorts of things from exhaust banging to wheel bearing suspension issues.

When someone reports a knocking from suspension a garage is unlikely to spend much time unless the knocking is either obvious or can be duplicated by bouncing or rocking or it is a very favoured customer.

Typically suspension/steering knocks and rattles do not cooperate and disappear once in the garage and so they must check the vehicle is safe and leave the rattle or knocking to develop. Lots of things can cause noise without being dangerous.

I was a mechanic in a garage in the days before time cost so much money and we took a different view of things. Then if someone brought us a rattle we mostly found it and cured it but sometimes the entire staff was employed driving around, bouncing, shaking , listening and sometimes it took hours. In those days the customer never paid for diagnosis - only the repair. That could not happen today...

On the right sort of road surface at the right sort of speed apparently good ball joints, steering racks and suchlike can produce awful noises. These sort of things often need to be checked and rechecked over a period before the source becomes obvious because road conditions cannot be duplicated in a workshop on a stationary car and no checking can be done on a moving car. It can take patience...

One typical knocking that is very difficult to locate is noisy valves inside the shock absorbers. Historically some car brands suffered a lot and others were no trouble at all so it is unsurprising some mechanics have never even heard the sort of racket they can produce that is obvious to no one except the occupants of the car.

Check your rear shocks. On the fender, push with your body going down. Upon releasing, your car should go up and down one time then settle. If it goes beyond or hesitate to move, you have a problem with your shocks. I think you also have a problem with the shock absorber bush. It does not matter if you have a new or old shock absorber. The lifespan of the shocks depends on the way you drive on bumpy roads.

Hard to say without hearing it but check front stabiliser "d" bushes for wear & check all subframe bolts are tight. Does the noise stop if you press the brake lightly.

Like most bikes, they come with pretty ordinary suspension, as you say, even on the softest setting, they are still not very comfortable. Most standard bike suspension is set up for a heavy person solo, or to carry a pillion passenger and luggage. The only suggestion is to customise your suspension. Ohlins are one of the best for the rear, or Koni. For the front, some new springs of a brand name, and good fork oil, with the correct amount of oil in each leg, mabey a little less if you want it softer.
Hope this helps.

Sounds like the Spring may be broken or there is another loose front end part such as a ball joint or a spring seat or something like that.

I had a broken spring on my 1990 Cadillac Deville and didn't know it until looking at it up under the wheel, and experiencing a popping or knocking sound when turning.

It could also be the bearing cap area problem.

check your stabilizer links common problem.one will have broken causing your noise.

Does it happen when you accelerate and decelerate? If so, it might be a motor mount or transmission mount. If it only happens on bumpy roads, check to see of the battery is held down tight, otherwise I'm at a loss.