hi guys im new here, im having problems with my engine rebuild on my dt125r its a 00 model, to start with there was water in the crankcase when i bought it but i never thought much of it as i was buying it to rebulid anyway, but now iv stripped the head and barrel off and checked the condition of the barrel and piston and all seems fine... but when i hold the con rod and lift i can feel slight play (up and down play) is this ok or do i need to replace bearings? the bike is for off road use only so doesnt need to be perfect.. and wot oil is best to use? cheers for any help.... oh and wot would be the cause of water in the crnkcase???

there shouldnt be any perceivable play in teh B/end bearing so it should be replaced

if it does fail they usually take the piston and or the barrel with them so its your choice but i know what i would do

as for the water most likely it is the water pump seal

yip guru you where spot on water pump was knackered as was seal and shaft.. so i got a new casing with good pump and seal thanks for all the help ... tho iv been told that my play in the bearing is mininal and nothing to stress over so il just replace it when im doin the bottom end... cheers