Author Topic: MKV tappet threads  (Read 475 times)

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Offline Pallijen15

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MKV tappet threads
« on: 11 Jun 2019 at 20:03 »
Hi, can  anyone tell me what threads the tappets are? I have just removed to put the correct locknuts on but I cannot unscrew the tappets all the way out of the arms. The locknuts that have been used were not of the same thread so want to run a die down in case I damage the threads in the rocker arm before I remove the tappet. The ends of the tappets can be seen as to have been pummelled a little. Should these be renewed at this point. Also, I am going to try with the locknuts on the inside of the rocker arm to get the full benefit of the thread. One side of the bike already has them on this way anyway. Any advice please. Thanks, Paul

Offline eddie

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Re: MKV tappet threads
« Reply #1 on: 12 Jun 2019 at 07:30 »
Paul,
         The tappet threads are 1/4"BSF. The tappets are often difficult to remove due to them being stretched by overtightening of the lock nuts. The rocker arms are heat treated (hence the copper plating), so are usually tough enough to resist being damaged by forcefully removing the screws - but be sure to lubricate the threads first!

  Regards,
                    Eddie.

Offline Pallijen15

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Re: MKV tappet threads
« Reply #2 on: 12 Jun 2019 at 11:19 »
Ok thanks Eddie, I read somewhere that the threads on a Douglas were 95% BSF, just didn't want to take a chance.

 

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