marty125
Active Member
hey guys i think my timing chain may need adjusting? my bike feels like its 'missing' i'm adjusting my valves tomorrow. but i'm pretty sure its my timing that needs adjusting. is there any way to do this?
timing chain
- Thread starter marty125
- Start date
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rider456
Well-Known Member
rider456
Well-Known Member
the bike will run when its out by one tooth just not well
ElstarB2Rider
Member
Correct Way Of Setting Cam Timing
hey MARTY125, ok, iv ripped the china 125cc engines all the way down tons of times, actually mines in peices right now! and way dont worry about chain tension because under the engine there is a bolt nere the oil drain bolt, i believe its a 14mm if you take it out there is a spring and rod that keeps tension on the chain and, lets just say the chain stretched "wich it wont" but the spring will take up the slack and put enough pressure on the roller and arm to keep everything good!!
as for your timing, take a look at your fly wheel and make sure its on TDC = top dead center and both valves are closed. The cam shaft has a sprocket bolted to it with 3 9mm bolts all you have to do is undo that 14mm bolt i told you about a couple of turns but not all the way out! then try and get enough slack in the cam chain to get the chain off the cam sprocket then with the cam chain off the camshaft sprocket, spin the cam shaft till the dot on the sprocket lines up with the notch/cut-out in the head/case. put the cam chain back on making sure the camshaft doesnt move!! HINT: when your puting the cam chain back on keep the bottom half of the chain tight because the tensioner works on the top so you pre tension the bottom and the tensioner tensiones the top part!! hope this helps REMEMBER DO UP THE 14MM BOLT ON THE BOTTOM OF THE ENGINE THEN YOUR FINISHED!! i own a chinese pitbike and to be honist i hate them and think they are cheap and nasty and we should all go japanese or euro but some people you cant for what ever reason! so ill try and help you fix it and i hope this helped! please comment back and let me know if this helps!!! cheers
hey MARTY125, ok, iv ripped the china 125cc engines all the way down tons of times, actually mines in peices right now! and way dont worry about chain tension because under the engine there is a bolt nere the oil drain bolt, i believe its a 14mm if you take it out there is a spring and rod that keeps tension on the chain and, lets just say the chain stretched "wich it wont" but the spring will take up the slack and put enough pressure on the roller and arm to keep everything good!!
as for your timing, take a look at your fly wheel and make sure its on TDC = top dead center and both valves are closed. The cam shaft has a sprocket bolted to it with 3 9mm bolts all you have to do is undo that 14mm bolt i told you about a couple of turns but not all the way out! then try and get enough slack in the cam chain to get the chain off the cam sprocket then with the cam chain off the camshaft sprocket, spin the cam shaft till the dot on the sprocket lines up with the notch/cut-out in the head/case. put the cam chain back on making sure the camshaft doesnt move!! HINT: when your puting the cam chain back on keep the bottom half of the chain tight because the tensioner works on the top so you pre tension the bottom and the tensioner tensiones the top part!! hope this helps REMEMBER DO UP THE 14MM BOLT ON THE BOTTOM OF THE ENGINE THEN YOUR FINISHED!! i own a chinese pitbike and to be honist i hate them and think they are cheap and nasty and we should all go japanese or euro but some people you cant for what ever reason! so ill try and help you fix it and i hope this helped! please comment back and let me know if this helps!!! cheers
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