Thx for answer me ! Perhaps it’s original HD pistons engines ?
But when a friend dealer search with the number inside, he find something like that but in 0,20 resize..
And i don’t find table size of cylinders and pistons..
Thx for answer me ! Perhaps it’s original HD pistons engines ?
But when a friend dealer search with the number inside, he find something like that but in 0,20 resize..
And i don’t find table size of cylinders and pistons..
Maybe that is an oversize piston???? Been a few years since it was new...
again a Parts Manual... and a Good Measureing device.
Depending what you are going to expect from this bike.. Having seen nothing to have been concerned enough to take it apart over... I would Hone and ring and go... But, Only done by a Qualified...BTDT Harley Machinist.... No Car nor Tractor Guys...
Racepres would know better than I but those valve seats sure look a lot close than I would expect them to be
Originally Posted by Le Vizir
Do you know this kind of piston ?
Don’t know the size..and origine ?
I too would suggest they are OEM pistons. Pistons below came out of a stock 1975 FXE that had been sitting for just over 20 years. Yours has similar markings and numbers on the inside. These did too. Best way to determine bore is to use a bore gauge. Gonna need to anyway in order to determine what size pistons you will need. Plus I have not seen aftermarket pistons with a date code on top of the pistons; just markings indicating what size over they are (.10, .20...and so on).
I expect Valve seats to be wide and terrible on old Shovelheads... especially ones that probably have had the Damn things Lapped!!!
I do My Valves anytime I have the heads off... certaily if the thing is getting rings..
Sunken valves [seats]??? well I don't worry as much as I used to... just address the Springs accordingly, and Roll....
Remove valves... paint seat and valve seat area with permanent Marker, Drop valve in light Pressure... maybe a partial spin... Show the Seat and Valve face... gonna tell ya what shape the valve job is in!!!!
BTW the service manual [the early ones anyway] show what you should be looking for... I modify my own a bit... but... it is not necessary to deviate from the Book!!!!
Finally... I have Not held those pistons in my hand... but many times the Pistons can certainly be re-ringed and run... better get a better look [and Measurement] of the bore tho..
I'm not sure I can spot any reason why that engine is apart!!!!!
I like it alot
I should have came with Drag bars... which some folks dislike
also the sissybar was standard equipment on the FXS, someone spent some time to remove it and then replace the signals..
the pistons are the oem originals the numbers on top is production grading as they match the piston to a cylinder to get the correct clearance on the assemble line
the reason the 46 degree angle is chewed up on the valve seat is it did not have seals and the carbon from the oil passing the rings or valve guides gets caught up in both the valve and the seat - carbon is as hard as tiny stones
I would plan on replacing the pistons with a set of .010 over stock compression is best 8 1/2 to 1 - replace the 4 valves as many 1970s original bikes still had steel valves not stainless < a magnet will confirm what you have - reason I said this it has o ring intake and its a 79 - cast iron valve guides is the best deal with stainless valves and the blue rubber valve seals - piston rings should be moly coated top ring - cast iron second ring and the oil ring 3 pieces each piston
take the front connecting rod and see if you can twist it clockwise and counterclockwise a small amount of twist is ok but only a small amount - most have zero if the lower unit is in great shape - my guess the condition of what I see it is more then likely ok no real movement
03-19-2019, 08:13 AM
