has the bike you are looking to purchase been in an accident ?
things to look for.
looking to buy a second hand bike.a few easy things you can do to check if the bike has been seriously dropped or laid down and damaged in an accident
Appart from the obviouse things like scrapes/scratches and dents that can been seen straight away(these are usually on the tank,side covers,left or right sides of engine etc,) There are some quick checks you can do to accertain if the bikes had a bad accident.
Note before doing any of these checks make sure the bike engine is not hot or you could burn yourself on the engine or exhaust.. (1) Put the bike on it centre stand,if it has one, and go to the rear of the bike and look down the bike ,lining up the back tire with the front tire.Check to see there is a straight line ,ie that the front tire is pretty much hidden from your view.If you notice the front tyre is obviously to one side instead of in line with the back tire there is a chance the frame is bent.Also check to see if the swinging arm is straight up and down.If it does not look staright vertically then there is a chance it could be bent.While you are there try holding the rear tyre securelly and try to move it from side to side.If there is movement here it could be that the swing arm bushes are damaged or worn and need replacement as this will affect the handling and tracking of the bike.
(2) Go to the front of the bike, have a friend or someone push the rear of the bike towards the ground ie, this will lift the front up to free the steering.Put your hands on the bottom of the front forks,get a good grip and pull to front and back.If you feel any movement chances are the head race bearings are not in good condition or have been damaged or are in need of greasing and tightning.This is not a small job and unless you are an experienced motorcyclist with good engineering skills I would let a motorcycle workshop repair the front forks.You can also check the fork seals by sitting on the bike holding the front brake on and pumping the forks several times.Hop off and put the bike back on its stand and run you finger over the stauncion.If there is excess oil/hydraulic fluid on your finger it could be that the fork seals need replacing,another motorcycle workshop job.
(3) Generally look closely all over the frame to see if you can spot any obviouse cracks or dents in the frame. Checking under the bikes exhasts,if they are a lower type of muffler etc,. Check the underside of the engine for damage.Often if the bike hits a curbing or something solid while sliding down the road and there is no bash plate to protect it there will be some signs of damage.
Doing these checks when looking to buy a second hand bike is good practice and will show the seller that you know what you are looking for and you appear knowledgable about bikes.
All the best and please dont hesitate to ask me questions.