cough Posted June 18, 2014 Share Posted June 18, 2014 Hello i want ask it is possible after changing 50cm3 to 70cm3 bore kit, clutch starts slip? I buy DT50MX 1991r with 70cm3 bore kit, and when i drive and put 5 gear and accelarate slow, everything are ok, but when i get full throtle my clutch slip. i change spring for new ebc, i measure old clutch plates and they are 3,45mm when new are 3,5mm .i dont have more idea what to do. Maybe someone here have dt50mx with bigger bore kit ? Link to comment Share on other sites More sharing options...
Moderator Cynic Posted June 19, 2014 Moderator Share Posted June 19, 2014 With that big bore you have doubled the horsepower and you and that clutch will now be very close friends. You need heavy duty springs as well as new plain and friction plates. If you can find one a DT 50 m (the earlier twin shock) had a stronger clutch. Although you will need the primary pinion too I think. Link to comment Share on other sites More sharing options...
cough Posted June 19, 2014 Author Share Posted June 19, 2014 my bore are airsal 70. i have new ebc spring. Link to comment Share on other sites More sharing options...
Moderator Cynic Posted June 21, 2014 Moderator Share Posted June 21, 2014 Doesent matter who makes it your clutch is slipping. Note it is slipping with the ebc springs. You need to replace the clutch plates. All of them and fit stronger springs. The heat from slipping will have damaged the ones you have. Link to comment Share on other sites More sharing options...
wild foamy Posted June 21, 2014 Share Posted June 21, 2014 I was running the 65cc bore kit and had a similar problem, change your oil and use the correct motorcycle only oil (not car oil, it contains mobylene!) The clutch should be sufficient to support the 70cc, they are relatively robust. Link to comment Share on other sites More sharing options...
cough Posted June 21, 2014 Author Share Posted June 21, 2014 i use motul sae10w40, service manual says 10w40, so oil are ok, i order new versah clutch plates. Link to comment Share on other sites More sharing options...
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