hi all , iv just bought a dt 125 re on a 05 plate 3k miles , theres a very loud tinny rattle from the top end its as if its coming form the front of the exhaust pipe (manifold) it also smoking alot it sounds as if its chockd when tryin to full throttle it , checked the air filter and it was wet with 2 stroke removed it and it revs abit better but still smoking alot . checked all coolants all fine and it aint loosing any , the bike ticks over on its own no probs. has any 1 got any ideas of what could be wrong with it , iv bought the bike as stolen recoverd so no doudt its had a good thrashing !!!!

a wet air-filter on a two stroke indicates that not all the fuel/air mix is being burnt during ignition.

so as the bike has been tampered with?? is the power valve/exhaust servo actually working/opening as that may have an effect??

have the throttle/carberettor screws been badly adjusted in an attempt to make it go faster???

are the oil pump settings right??

does the bike have an air leak some-where causing poor combustion???

you say it`s smoky??? does it need a de-coke??

or is it just friar-tucked..

i am not saying this is gospel but that is what i would be looking at it this bike was mine

hi all , iv just bought a dt 125 re on a 05 plate 3k miles , theres a very loud tinny rattle from the top end its as if its coming form the front of the exhaust pipe (manifold) it also smoking alot it sounds as if its chockd when tryin to full throttle it , checked the air filter and it was wet with 2 stroke removed it and it revs abit better but still smoking alot . checked all coolants all fine and it aint loosing any , the bike ticks over on its own no probs. has any 1 got any ideas of what could be wrong with it , iv bought the bike as stolen recoverd so no doudt its had a good thrashing !!!!

The rings have bust and are catching the exhaust port, if you are lucky a set of rings and a decoke, if not a full top end work over. Bore, new piston, rings, little end, etc.

Sounds like the theiving fcukers thrashed the thing to within an inch of its life.

a wet air-filter on a two stroke indicates that not all the fuel/air mix is being burnt during ignition.

so as the bike has been tampered with?? is the power valve/exhaust servo actually working/opening as that may have an effect??

have the throttle/carberettor screws been badly adjusted in an attempt to make it go faster???

are the oil pump settings right??

does the bike have an air leak some-where causing poor combustion???

you say it`s smoky??? does it need a de-coke??

or is it just friar-tucked..

i am not saying this is gospel but that is what i would be looking at it this bike was mine

, hi there , the carb settings seem fine the engine is in mint condition but sounds naff lol , the spark plug is very wet (black oil) il try the easy options 1st decoke etc .the power valve looks as if its been tampered with it clicks when i turn it on so at a guess its working ok may be just set up wrong . im used to the old dt 125 they sounded alot different as all the old 2 strokes did . when i rev the bike the clickn goes . could it just be that theres so many valves etc on these they sound totaly differenrt ??? as far as the smoke could it just be shity cheap 2stroke ??

The rings have bust and are catching the exhaust port, if you are lucky a set of rings and a decoke, if not a full top end work over. Bore, new piston, rings, little end, etc.

Sounds like the theiving fcukers thrashed the thing to within an inch of its life.

thanks for the reply , is there any test i can do just to confirm it could be the rings ??? il try and give it a decoke etc 1st . daft question but on the carb is the choke on these up 4 on and down 4 off ??? its hard to tell with the bike running shite ..

thanks for the reply , is there any test i can do just to confirm it could be the rings ??? il try and give it a decoke etc 1st . daft question but on the carb is the choke on these up 4 on and down 4 off ??? its hard to tell with the bike running shite ..

Im sorry to say, its v havd to find one of these bikes that the shite hasnt been driven outa it.

The choke will be on when the leaver for (up + down) has the little choke barel pulled out.

There is no real test to confirm if it is the rings broken, the loud tinny rattle will b at its worst when the bike is started first and cold.

Noises dont come from your engine for no reason (hence) it is the rings broken and if you v "lucky" it might not b needing a rebore.

Sorry mate but you have a bit of work to do !

Go for a hard spin if you can for an hour then check plug condition again.

Im sorry to say, its v havd to find one of these bikes that the shite hasnt been driven outa it.

The choke will be on when the leaver for (up + down) has the little choke barel pulled out.

There is no real test to confirm if it is the rings broken, the loud tinny rattle will b at its worst when the bike is started first and cold.

Noises dont come from your engine for no reason (hence) it is the rings broken and if you v "lucky" it might not b needing a rebore.

Sorry mate but you have a bit of work to do !

Go for a hard spin if you can for an hour then check plug condition again.