Interesting.  I checked the 72 DT2 and you're right they added a Part #15 gasket between the manifold and the muffler.  This fix is exactly what is needed and relatively easy to do.   

perfect! Thanks everyone 
 

yep 15 is just the string packed in the slot for pipe to push against but think that what you mean!!.

Hey guy I did what you said and it worked perfectly!  Thanks again.  

Who is Guy?! 

Glad you got it sorted.

If you have persistent oil blowing out of the exhaust with or without the oil injection pump check ball and spring in place. You could very well have a bad crankshaft seal on the clutch side. Surprised nobody mentioned this..

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Thank you ASCO for your comment.   I would like to know more why you believe that a crankcase seal leak may result in a manifold oil leak?  I am relatively new at this stuff and always looking to learn more.   I had a seal leak on the clutch side and recently replaced all of the seals.   That doesnt mean they dont leak anymore; however, I did do a leak down test and it appeared that the lower end was fairly air tight.  I have yet to give the bike a full test run and so I would like to hear more about your thinking in case I need to further trouble shoot this issue.

Cheers and thanks again for you comment and feedback....look forward to hearing your response.

'My opinion only' but crank seals are very robust on those motors. Unless your oil level is disappearing fast on the trans dipstick in my opinion it'll be good. On the smaller motors that right side crank seal can get forced out & let trans oil into the crankcase. Good thinking from 'asco' in #15 though.--& the pump ball & spring.

While it is very true that the DT1 seal on the crankshaft side out lasts most AT1's and CT1's by far If you are losing oil on the right side it must to go somewhere. It's not all going to get burned up.

I remember in the past somebody had a bike I believe it was a Suzuki twin that was leaking oil that was not greenish or brownish out of the header. The diagnosis was a crankshaft seal. Just thinking out loud.

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