This page shows the type of work we can do to improve the reliability and performance of any original head for any motor.

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Sportster Ironheads with Hardened Seats —
Run your old bike reliably on today's gas!

Hardened valve seats are a must these days, and have been for many years since the anti-knock agent (and octane booster) known as tetraethyl lead was taken out of gasoline. With seat work like that shown below, your ironhead Sportster motor will be ready for many, many reliable miles running on the crap they pass off today as gasoline!

Other aspects of the heads on this page:

• They are not ported. They are more like an antique restoration with a twist.
• To survive on today's fuel, the old valve seat area was machined out, and hardened seats were pressed in.
• These heads have a five-angle valve job. This allowed us to shape the seat to extract more horsepower.
• Installing the new seats allowed us to bring the valve stem height back to the original height they would've had when the engine was new.
• On these resto-type heads, we're using severe duty stainless steel Manley valves with Rowe USA Ampco 45 bronze guides. (Note that our performance heads use a different combination: Cast iron guides with German nitrided stainless steel valves.)

And now the motor can run on unleaded fuel with no worries!

One common element: both variations have Manley .495-in lift spring kits installed.

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