gave my lads techno 250 an oil change the other day as the oil was very milky looking,changed and flushed out but after a days ridding its milky again...

there also seems to be a knock coming from engine doesnt seem to get louder or faster with revs but still knocks...engine was seamingly rebuilt before i bought it...what should i be looking at doing to rectify the problem..it starts and runs fine no loss of power and fires up first kick hot or cold..

I had this problem with my Sherco recently. Cant speak for Beta's but if its the same as a Sherco its water getting in through the seal into the gearbox oil and emulsifying with the oil. you need to change the seal around the water pump. check the water level in the radiator, my guess is it will have dropped. be cautious if you ride it - best to get it fixed. water & clutch plates not a happy combo.

I'm sure other Beta riders can offer more advice than this, but it sounds exactly the problem i had. no idea what the knock is i'm afraid.

Good luck.

i had an idea it may have been this ,i have a seal on its way,anyone any idea how easy it is to fit..

very simple quick job check the shaft for wear while your there

Easy job m8 just done it on my beta evo. Just drain the coolant thro the small screw on waterpump, take out the 3 bolts that hold waterpump on then just pull it away from casing, i put a cable tie thro one of the holes up to exhaust just to hold it awan then you can access the spindle, all you have to do is pick the old seal out with a screw driver (small) then replace the seal (thake note wich way seal goes on as the sides are not the same) push seal on, i used a small socket just to push it in correctly, build back up easy make sure seal on waterpump is on correctly that goes on waterpump to casing, use a bit of greese if it falls out just to hold in place bolt back up put screw in for the drain of coolant and fill back up with coolant, you dont even have to remove the hoses on it, give it a good blast about drop oil out and replace with new check coolant again because sometimes drop a little, good point to check breather pipes to make sure they are on and aso egnition cover give it a good spray with wd40, hope this helps

thanks for that will give it a go when seal comes,and hopefully that will cure the prob...

I've also just done it on my evo every easy job but remember which way the seal goes in.

Hope it's just the seal / shaft,

Betas used to have a problem with the magnesium rich alloy eroding in the waterpump, made worse by insufficient antifreeze in the coolant.

I'd take the pump cover off and have a look before you order any parts

Yes that is true about the coolant eating it away, had same problem on my rev3

Hope it's just the seal / shaft,

Betas used to have a problem with the magnesium rich alloy eroding in the waterpump, made worse by insufficient antifreeze in the coolant.

I'd take the pump cover off and have a look before you order any parts

Thats why you should change it for Silkolene PRO COOL.