Harley Stroker?
Elite HDF Member
Joined: Dec 2009
Posts: 4,598
Likes: 14
From: navarre ohio
most old stroked harles are just BS. a guy used to come into the shop i worked at all the time, that talked about his 1790cc stroked ironhead with stock cases and cylinders..they made kits,and parts but they wernt that commen, you had to add lifter blocks under the cylinder for the extra stroke room,and make a custom intake and exhaust to fit it..all the parts are available now for newer bikes, but you should still be carfull buying one..
Road Warrior
Joined: Oct 2007
Posts: 1,599
Likes: 11
From: Colonial Beach, Virginia
I never figured a stroker was a good idea, stroking increases the piston speed, feet Per Minute for a given rpm and also the piston feet per mile increasing wear but the biggest bugaboo is the increased g-forces at the ends of the stroke. Unless stronger components are used reduced rpm is a must.
Road Warrior
Joined: Oct 2007
Posts: 1,599
Likes: 11
From: Colonial Beach, Virginia
True, but you can also get them by boring the cylinder. People get too hung up on the old, "longer stroke equals more torque" and "larger bore equals more revs" The valve timing has far more effect on the torque vs rpm amounts than the bore or stroke. People tend to forget that a larger bore has more square inches of piston area for the combustion pressure tp push on. Also a larger bore shorter stroke engine running at higher rpm has more power pulses per minute.
In our engines though we like the sound and feel of the longer stroke engines.
In our engines though we like the sound and feel of the longer stroke engines.
6th Gear
Joined: Nov 2010
Posts: 14
Likes: 0
Bored and stroked
What should a person look for if buying a bike that has had the engine "bored and stroked"? Before reading some threads I was seriously thinking of buying an 05 1200C Sportster that supposedly has been bored and stroked to 1340cc. Having asked some questions of the seller, such as what was done and where and by whom, and having gotten no reply, I am now not so sure, but would like to know more. All input greatly appreciated.
Novice
Joined: Dec 2010
Posts: 19
Likes: 0
DeepSea. All '04+ XL's are mildly stroked, the 883 more so than the 1200. 3.00" bore and a 3.8125" stroke on the 883, 3.5" bore with a 3.8125" stroke on the 1200.
If the piston stroke, is longer than the diameter of the cylinder bore, it's a stroker.
If the piston stroke, is longer than the diameter of the cylinder bore, it's a stroker.
Guest
Posts: n/a
No, if the stroke is longer than the diameter of the bore, it's "under-square." A "stroker" is when the stroke has been increased beyond the original factory configuration. No factory anything is a stroker.
Novice
Joined: Dec 2010
Posts: 19
Likes: 0
Tekdiver. I'll stand by my original comment. And more than a few H-D's have been factory strokers, probably the most radical being the 1954 KH, 3" pistons and a stroke of 4.562". Stroker isn't an aftermarket phenomenon, it is a physical phenomenon, and anybody can do it, factory or S & S, or you if you have the tools and know-how. S & S out of Viola, Wisconsin wrote the book on stroking a Harley, maybe this is why people think it's "beyond factory", and their strokers are very fiine and proven powerplants, but they didn't invent stroking, it's simply a particular engine geometry, with its' own set of advantages & disadvantages.
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Road Captain
Joined: May 2007
Posts: 713
Likes: 2
From: Pa.
Isnt the 96c.i. in the new big twins a stroked 88 c.i.? Harley put the 103 crank in the 88 twin cam with the 88 jugs. bore the 88 you get a 95 keep the stock bore and add the crank you get 96, bore the 96 you get a 103....jus sayin stock stroker...........not?
Tourer
Joined: Mar 2007
Posts: 375
Likes: 1
From: Jackson NJ
What should a person look for if buying a bike that has had the engine "bored and stroked"? Before reading some threads I was seriously thinking of buying an 05 1200C Sportster that supposedly has been bored and stroked to 1340cc. Having asked some questions of the seller, such as what was done and where and by whom, and having gotten no reply, I am now not so sure, but would like to know more. All input greatly appreciated.
