1973 ironhead cylinder boring work
#1
03-17-2014, 05:35 PM
Join Date: Feb 2014
Location: NE Ohio
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#2
03-17-2014, 07:20 PM
Seasoned HDF Member
go to a car speed shop and ask around - call the local drag / circle / dirt track and ask who sponcers the the track from a race machine shop - for that matter the lawn mower guy does cylinders --
#3
03-17-2014, 08:43 PM
I would recommend to continue being careful what type of shop you choose. It is important IMO to choose a shop that regularly works on vintage, cast iron engines. The tech's in modern machine shops who work on only modern auto etc engines do not have the knowledge and experience to do a proper job on what you have. Ask around, yes, but for this specific type of shop.
#4
03-17-2014, 08:52 PM
Seasoned HDF Member
#5
03-17-2014, 09:48 PM
Tourer
[QUOTE=johnjzjz;12454009].004 or .005 thousands piston to cylinder wall clearance, and the hone straight to the .0001 is the same if the guy does it in a meat packing factory or his nascar shop --
I disagree. I've bored dozens of iron head cylinders, including re-boring ones bored by the best car race shop in my area, and a lot of them were never bored correctly, from the factory, or thereafter. You can have a perfectly fit cylinder, that it totally out of whack with the centerline of the crankshaft. I have had to bore three to four oversizes to have them come true with the center of their world. Many use a Sunnen cylinder hone and just follow an already bad hole.
I disagree. I've bored dozens of iron head cylinders, including re-boring ones bored by the best car race shop in my area, and a lot of them were never bored correctly, from the factory, or thereafter. You can have a perfectly fit cylinder, that it totally out of whack with the centerline of the crankshaft. I have had to bore three to four oversizes to have them come true with the center of their world. Many use a Sunnen cylinder hone and just follow an already bad hole.
#6
03-18-2014, 07:40 AM
Seasoned HDF Member
[QUOTE=ranchodeluxe;12454275]
all of that might and is true to a degree - we use a CK 15 -- but harley from the begining used an hand operated, hand held end hone, walked it one way then turned it around all the while its in your hands and do the other side ( top or bottom ) crued for sure 50 maybe 80 years of harley engines in shops did it this way but the have a bore gage
in a real auto machine / race shop Doing /// FIXED blocks //// that are machined off the cranks center line you are correct, the center has to be held ( deck top to crank center line at the correct degree of angle ) BUT what flat surface is it that was used becomes the issue -- pan rail or the deck can and is at times indifferent from the crank center line -- depending on core shift you are correct again it may end up a bigger bore to correct mas production mistakes that happen -- anyway that is not what we have
BUT this is // and NO way i am awair of unless you have a lazer guided machine that picks a center out of the air does that have a play in an multi piece bolt together 2 cylinder block with with moveable bolt together parts - it took till 1984 the EVO engine before they used a pin to locate the cylinder and even that is well is the pin in the right spot as well as the barrel -- and shops i know still hand hold evos and twinkies - and hone to fit cylinders off an end hone -- you know if a sunen bore gage tells you its round top to bottom its round what is it then not round
SO i guess you are using the base of the barrel as the location of the crank center line - or how did you come to know what it is ??????????????? your turn -- johnjzjz
.004 or .005 thousands piston to cylinder wall clearance, and the hone straight to the .0001 is the same if the guy does it in a meat packing factory or his nascar shop --
I disagree. I've bored dozens of iron head cylinders, including re-boring ones bored by the best car race shop in my area, and a lot of them were never bored correctly, from the factory, or thereafter. You can have a perfectly fit cylinder, that it totally out of whack with the centerline of the crankshaft. I have had to bore three to four oversizes to have them come true with the center of their world. Many use a Sunnen cylinder hone and just follow an already bad hole.
I disagree. I've bored dozens of iron head cylinders, including re-boring ones bored by the best car race shop in my area, and a lot of them were never bored correctly, from the factory, or thereafter. You can have a perfectly fit cylinder, that it totally out of whack with the centerline of the crankshaft. I have had to bore three to four oversizes to have them come true with the center of their world. Many use a Sunnen cylinder hone and just follow an already bad hole.
in a real auto machine / race shop Doing /// FIXED blocks //// that are machined off the cranks center line you are correct, the center has to be held ( deck top to crank center line at the correct degree of angle ) BUT what flat surface is it that was used becomes the issue -- pan rail or the deck can and is at times indifferent from the crank center line -- depending on core shift you are correct again it may end up a bigger bore to correct mas production mistakes that happen -- anyway that is not what we have
BUT this is // and NO way i am awair of unless you have a lazer guided machine that picks a center out of the air does that have a play in an multi piece bolt together 2 cylinder block with with moveable bolt together parts - it took till 1984 the EVO engine before they used a pin to locate the cylinder and even that is well is the pin in the right spot as well as the barrel -- and shops i know still hand hold evos and twinkies - and hone to fit cylinders off an end hone -- you know if a sunen bore gage tells you its round top to bottom its round what is it then not round
SO i guess you are using the base of the barrel as the location of the crank center line - or how did you come to know what it is ??????????????? your turn -- johnjzjz
Last edited by johnjzjz; 03-18-2014 at 07:45 AM.
#7
03-18-2014, 04:57 PM
Join Date: Feb 2014
Location: NE Ohio
Posts: 28
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I would recommend to continue being careful what type of shop you choose. It is important IMO to choose a shop that regularly works on vintage, cast iron engines. The tech's in modern machine shops who work on only modern auto etc engines do not have the knowledge and experience to do a proper job on what you have. Ask around, yes, but for this specific type of shop.
P.S. lawn mower guy, really?
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#8
03-18-2014, 06:49 PM
Seasoned HDF Member
That's what I'm working on Mick. I think I may have found a place localy. The owner is an old school Harley guy. Built and has some vintage bikes him self. Told me he is tooled up for castings or sleeve. I will pay him a visit Saturday and see how things go. Thanks for all the help guys.
P.S. lawn mower guy, really?
P.S. lawn mower guy, really?
thats more than your iron head BTW and it a lawnmower
#10
03-18-2014, 11:13 PM
Tourer
[QUOTE=johnjzjz;12455273]
all of that might and is true to a degree - we use a CK 15 -- but harley from the begining used an hand operated, hand held end hone, walked it one way then turned it around all the while its in your hands and do the other side ( top or bottom ) crued for sure 50 maybe 80 years of harley engines in shops did it this way but the have a bore gage
in a real auto machine / race shop Doing /// FIXED blocks //// that are machined off the cranks center line you are correct, the center has to be held ( deck top to crank center line at the correct degree of angle ) BUT what flat surface is it that was used becomes the issue -- pan rail or the deck can and is at times indifferent from the crank center line -- depending on core shift you are correct again it may end up a bigger bore to correct mas production mistakes that happen -- anyway that is not what we have
BUT this is // and NO way i am awair of unless you have a lazer guided machine that picks a center out of the air does that have a play in an multi piece bolt together 2 cylinder block with with moveable bolt together parts - it took till 1984 the EVO engine before they used a pin to locate the cylinder and even that is well is the pin in the right spot as well as the barrel -- and shops i know still hand hold evos and twinkies - and hone to fit cylinders off an end hone -- you know if a sunen bore gage tells you its round top to bottom its round what is it then not round
SO i guess you are using the base of the barrel as the location of the crank center line - or how did you come to know what it is ??????????????? your turn -- johnjzjz
Secrets are a bitch, aren't they?
all of that might and is true to a degree - we use a CK 15 -- but harley from the begining used an hand operated, hand held end hone, walked it one way then turned it around all the while its in your hands and do the other side ( top or bottom ) crued for sure 50 maybe 80 years of harley engines in shops did it this way but the have a bore gage
in a real auto machine / race shop Doing /// FIXED blocks //// that are machined off the cranks center line you are correct, the center has to be held ( deck top to crank center line at the correct degree of angle ) BUT what flat surface is it that was used becomes the issue -- pan rail or the deck can and is at times indifferent from the crank center line -- depending on core shift you are correct again it may end up a bigger bore to correct mas production mistakes that happen -- anyway that is not what we have
BUT this is // and NO way i am awair of unless you have a lazer guided machine that picks a center out of the air does that have a play in an multi piece bolt together 2 cylinder block with with moveable bolt together parts - it took till 1984 the EVO engine before they used a pin to locate the cylinder and even that is well is the pin in the right spot as well as the barrel -- and shops i know still hand hold evos and twinkies - and hone to fit cylinders off an end hone -- you know if a sunen bore gage tells you its round top to bottom its round what is it then not round
SO i guess you are using the base of the barrel as the location of the crank center line - or how did you come to know what it is ??????????????? your turn -- johnjzjz
Secrets are a bitch, aren't they?