107 vs 110 kit
HDF Community Team
Joined: Jun 2006
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From: san antonio
"Jugs" = cylinders and the spigot is the part of the cylinder liner that fits into the cases. Actually, although the 110" spigots are thin, the liner is made from a high strength steel liner, so no worries. On the other hand, the 107" cylinder spigots are also thin but the OEM liner is made from ductile iron, not as strong as the new 110" cylinder liners. When builders like Hillside and VeeTwin started boring OEM cylinders to 98"/107" some were concerned with the thin spigots ability to maintain cylinder stability under operating conditions but those concerns have long been forgotten. Many 98"/107" "kits" up and running with no issues.
As others have said, boring to 107" is more cost effective than going the 110" route and, with parts that play well together, a well built 107" motor will satisfy; however, there is a lot to be said for biting the bullet and doing a big inch build/crate motor once and no buyer's remorse for not going big later. It all boils down to how fast do you want to go and how much money are you willing to spend to get there.
As others have said, boring to 107" is more cost effective than going the 110" route and, with parts that play well together, a well built 107" motor will satisfy; however, there is a lot to be said for biting the bullet and doing a big inch build/crate motor once and no buyer's remorse for not going big later. It all boils down to how fast do you want to go and how much money are you willing to spend to get there.
Club Member
Joined: Mar 2016
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From: Clearwater, Idaho
You can't bore from 103" to 110", as the cast liners will be waaay too thin and weak. You need one of the 110" kits that have the steel liners with the thin spigots. Or you need to bore the cases to accept the 110" cylinders that have the standard thickness spigots.
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OEM cylinders cannot be bored to accept a 4" piston(110")as the spigot will become to thin, and unstable with the OE cast iron material.
You can, however, bore your cases to accept a 4.125" cylinder/piston, and build a 117", with your existing 4.375" crankshaft.
130 hp and 135 ft/lbs, in tame form.
Scott
You can, however, bore your cases to accept a 4.125" cylinder/piston, and build a 117", with your existing 4.375" crankshaft.
130 hp and 135 ft/lbs, in tame form.
Scott
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Joined: Sep 2009
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From: deland,florida
SE or S&S have 110" bolt in kits for 96"/103" (S&S are on hold for a bit after HD sued them,their coming out with a new design soon)
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Road Master
Joined: Dec 2017
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From: New York
I have a 107 build in my Road King currently at 100hp/105tq. I'm looking for more power and my guy recommended 2 options. Add the heads for some minimal yet noticeable gains. Or do the 110 drop in, jugs,cylinders and heads and expect 120-130hp. I'm still debating. Looking at a 1200 price difference buttttt if I'm not going to be satisfied with the little gains might just go for broke.
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Joined: Jan 2009
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From: Ottawa, Ontario
Originally Posted by miketv84
I have a 107 build in my Road King currently at 100hp/105tq. I'm looking for more power and my guy recommended 2 options. Add the heads for some minimal yet noticeable gains. Or do the 110 drop in, jugs,cylinders and heads and expect 120-130hp. I'm still debating. Looking at a 1200 price difference buttttt if I'm not going to be satisfied with the little gains might just go for broke.
Jim