Idle + clutch Problems

[Candy_Salad]

I just had my it175 rebuilt and my friend who rebuilt it put thicker oil in it for the break in, so when i start my bike i have to let it warm up or else every time i go to put it in gear with the clutch in its like as if i never pulled the clutch and the bike dies. when warmed up shifts into gear great. after about 10-20 min i'll be slowing down, clutch in and my idle redlines until i release it back into gear

any ideas what could be the problem or problems?
Thanks

 

[2strokerfun]

after about 10-20 min i'll be slowing down, clutch in and my idle redlines until i release it back into gear

Do you mean the engine revs uncontrollably?? If so, does it also do this when you put it in neutral after warmed up??

First, warm up bike, turn off and drain oil. Refill with correct viscosity. See how it reacts. I break an engine in with the correct oil. Years ago, I used to use non-detergent oil to break them in, but still I used the correct weight.
As for the revving (if that's what you mean), sounds like you might have an air leak that doesn't surface until bike is warmed up. Could be a base gasket, seal or carb boot. Of course, first check the throttle cable to make sure it's not bound and your carb slide is returning easily to idle.