gn250

[Chrisnewtobikes]

Hi Iv just got a gn250,its got a tapping sound coming from the bottom of the left side of the engine,seems loader when engine is reving slow and then seems to go when revs are above 3500,any idears?

[Conquiztador]

Normally very hard to decide where a noise comes from in a motor. Doctors stetoscope is a good tool!

But if you are certain it is l/h front then you have the magneto there. L/h side cover comes off easily with a few screws and you can have a look. Rotor could be loose.

If the noise only comes when you ride and not as you stand still, then would be from chain.

Problems with crank end bearing and/or big end bearing can show up more at low revs initially. But will soon get worse and then there is no guessing anymore. Sadly.

Good Luck!

[Chrisnewtobikes]

Thanks for that will have alook

[autobatch]

I had a GN250 that I drove the length of the North Island. It was very noisy and I tried everything to quiet it down with no real success. I even changed the piston but that didn't help. I did discover, however, that valve clearence adjustment can make quite a bit of difference. If the gap is too large you get lots of noise and it is impossible to tell where it is comming from. It is fairly easy to adjust the valves yourself but take your time and make sure you get it within specs. If the noise is comming from the big end bearing, it will get louder as you remove power and quiet down as you apply power. If the noise is constant regardless of power, it is not the big end. My best advice is to just ignore the noise or better yet, get a Honda.