HarleyTechTalk

Technical Forums => Iron Head => Topic started by: Buglet on February 08, 2021, 12:28:26 PM

Title: Head
Post by: Buglet on February 08, 2021, 12:28:26 PM
   Here's a head you don't see every day, off a 900. 
Title: Re: Head
Post by: SP33DY on February 08, 2021, 03:06:57 PM
Looks like an XR head to me.
Title: Re: Head
Post by: Hillside Motorcycle on February 09, 2021, 04:23:13 AM
XR Head?
Title: Re: Head
Post by: Buglet on February 09, 2021, 05:28:36 AM
    Close but no, it's was call a Thunderhead made in the 70's to bolt onto XL's
Title: Re: Head
Post by: sharkoilfield on February 18, 2021, 11:52:28 AM
i had a search on eBay for a long time, never did see any
Title: Re: Head
Post by: DA71FX on March 26, 2021, 05:53:20 AM
Wow, I have not seen a set of those since the late 90s...I really regret that I let a pair go back in 99......
Title: Re: Head
Post by: Burnout on March 26, 2021, 08:41:04 AM
Thunderheads or XR heads are not the holy grail many think.

I've let lots of them pass me by, on purpose. 

Dual plug your stock heads and make sure the piston comes all the way up, then ride it like you stole it!
Title: Re: Head
Post by: JW113 on March 26, 2021, 10:01:16 AM
The guy that did the headwork on my previous ironhead (Ironhead Tom, RIP), was a drag racer in southern Minnesota. Although I did not have him do this to my heads because of the cost involved, on his drag bikes he would weld up the ports to reshape and increase velocity. I don't recall exactly what he was getting in terms of HP, but do I recall it was a lot. Zippers also used to do some magic to get impressive numbers from ironheads. Hey, all it takes is money, right?
:SM:

-JW
Title: Re: Head
Post by: Burnout on March 26, 2021, 10:17:04 AM
Anything can be made fast with the correct financial backing.

It doesn't take much to be faster than 95% of the bikes out there. You have to know when to shift too.  :scoot:
Title: Re: Head
Post by: Hossamania on March 26, 2021, 10:24:19 AM
Horsepower is in the heads. If you want to make a small fortune racing, start with a large fortune!

Quote from: Burnout on March 26, 2021, 10:17:04 AM
Anything can be made fast with the correct financial backing.

It doesn't take much to be faster than 95% of the bike riders out there. You have to know when to shift too.  :scoot:

Fixed that for ya...
Title: Re: Head
Post by: JW113 on March 26, 2021, 12:15:44 PM
Quote from: Burnout on March 26, 2021, 10:17:04 AM
Anything can be made fast with the correct financial backing.

OR, with a lot of skill and the right tools. I don't IH Tom spent a lot of money, but he sure spent a lot of time and had an well equipped shop.

-JW
Title: Re: Head
Post by: kd on March 26, 2021, 08:29:59 PM
"The only thing faster than cubic inches is cubic dollars ".  (Grumpy Bill Jenkins).  :wink:
Title: Re: Head
Post by: JW113 on March 27, 2021, 11:34:56 AM
While that is probably true most of the time, has anyone beaten Burt Munro's land speed record? Old Burt had no money, but an awful lot of skill.

-JW