NRHS is based in the beautiful city of Berthoud, Colorado. If you are ever in the area, come check us out! We love to talk shop and would be happy to show you around.


Although NRHS is known for our premier head porting and conversion kits, we do so much more!


We provide a wide range of services from simple oil changes to "all-out" performance engine builds. Dyno tuning is also available by appointment.




Got more questions? Call us! 970-532-3344 We would love to hear from you!





Please be advised if ordering from our website, Paypal does not charge international shipping. After receiving your order we will send you a separate Paypal invoice for shipping charges.





Price Breakthrough!


1250cc kits on sale!!  Only $699.95


1250cc conversion kits are now available in iron lined aluminum construction at this low price!




Why settle for 1200cc when you can have 1250? The legendary NRHS 1250cc  kits are now available for an unheard of price. Step up to the power of a 1250 kit today!


Iron lined aluminum 1250cc kits are now available at this terrific price in either silver, black or black with highlighted fins painted finish. Kits include brand new bored and honed cylinders, forged piston kits with rings and Cometic head/base gasket kits.  These kits are ready to bolt on, no case boring required.


We have kits available for all 1986 and up Sportsters and Buells. 



Please call 970-532-3344 for further details.


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Now Available Online: the NRHS catalog  (5 MB)


FREE Hardcopy: Click here to request your NRHS catalog by mail*


Install your engine kit right: NRHS General Instruction Sheet


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 unless otherwise noted, are the property of NRHS V-Twin Performance LLC and/or Nallin Racing Head Service LLC.

All Rights Reserved.

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