top end engine tap

Energy One
On my 05 mastiff I recently starting hearing a tap from front top area of engine, sounds like load sewing machine when running. I had the rockerboxes check and only normal wear, pushrods check but appear to be fine, bleed down test was fine and bike runs great with 25-30psi of oil pressure. checked for exhaust leaks and head gasket and all seems good. Just looking for help or idea for what else I should check, running mobil 20-50 and no metal in oil when changed
 

Alexey

Active Member
I do not know how to work a sewing machine. Check oil tappet screen. Describe your problem in more detail.
 

cdogg556

Guru
Is this a new sound that just started or got louder? :oldconfused:I have always said that my rocker boxes sound like a loud sewing machine, I believe that is completely normal.:old2:
Also Mike, you might wanna do an intro before posting in the forum,:yesnod: this is just kinda a respect thing around here and so we can get to know ya a little better!:cheers:
 
I do apologize, hey I am new to big dog but let me intro my self. I did some moto cross some 20 years ago on rm125, then moved to car club crap with AC cobra kit car with 427 sidewinder blown to 975hp, then wanted to do some racing so moved to shifter kart racing for a couple years but got to old and fat to be competitive so I bought my 05 mastiff about 2 years ago and have loved it. Ok so that me and I do get being part of the forum and not just using it as a source to make repair. the tapping noise is from the front cylinder and sounds like rockerbox area. the sound works with the throttle as it increases with throttle. speed of tap not loader. It really sounds like standard rocker tap but just much loader and yes it always made the noise but know seems loader. bike has 12k miles and I even check compression releases. like I said bike run great just noise makes me nervous and I am anal and cannot stand having people come up and ask me what that noise is when we are out on a ride. Thanks again for any help or insight.
 

cdogg556

Guru
I do apologize, hey I am new to big dog but let me intro my self. I did some moto cross some 20 years ago on rm125, then moved to car club crap with AC cobra kit car with 427 sidewinder blown to 975hp, then wanted to do some racing so moved to shifter kart racing for a couple years but got to old and fat to be competitive so I bought my 05 mastiff about 2 years ago and have loved it. Ok so that me and I do get being part of the forum and not just using it as a source to make repair. the tapping noise is from the front cylinder and sounds like rockerbox area. the sound works with the throttle as it increases with throttle. speed of tap not loader. It really sounds like standard rocker tap but just much loader and yes it always made the noise but know seems loader. bike has 12k miles and I even check compression releases. like I said bike run great just noise makes me nervous and I am anal and cannot stand having people come up and ask me what that noise is when we are out on a ride. Thanks again for any help or insight.
Great job Mike, copy and paste to the "Introductions" forum and you'll be set brother!:old2::cheers:
 

woodbutcher

Mr. Old Fart member #145
Staff member
how many screws are on the top of the rocker boxes, 4 or 6? 4 is TP (not good) 6 is S&S (good). lots of threads about the situation.
 
4 bolt, yes the TP rocker. I did see a lot of threads but no one had answer. Can rocker box be changed out with S&S cover or not that easy. Like I said I love the bike don't want to be just another HD driving a Road King or Road glide in all black.
 

Alexey

Active Member
4 bolt, yes the TP rocker. I did see a lot of threads but no one had answer. Can rocker box be changed out with S&S cover or not that easy. Like I said I love the bike don't want to be just another HD driving a Road King or Road glide in all black.
Nothing wrong. I have TP. Normally. Adjust carefully and everything is OK. Try 3.5 turns.
 
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