Difference in frames

[Lostcause]

I was wondering if there was any differences in the frames of the Ironhead from 74 to 78. I found a weld-on/bolt-on hardtail in J&P that is for up to 74 (which someone on this site used on his '74), and a bolt-on only that goes til 78. I have a 78 ironhead, but I like the looks of the welded hardtail vs. the bolted. Does anyone know by chance if this kit for a '74 model will work on my '78?

Mike

[ghostrider 61]

I cut and pasted any frame information I could find from the Sportster Home Page. It's a good Sporster page if you want to check it out, here's the URL: http://www.sportster.org/


1975:
Left hand side gear shifting, right hand side rear brake (Fed mandated) - that may have caused some modifications to the frame (not sure)

1977:
New cases to accommodate the left side shifting.
Frame designed for removal of oil pump with engine in frame.

1978:
Battery and oil tank moved inboard - again maybe some small change in the frame

1979:
All models got the XLCR frame and exhaust (Siamese).

DB

[Injdog]

I bought the exact same weld-on hardtail section from J&P. To get the right look and fit I had to modify (slightly) the under seat post section. I replaced the entire back bone with a larger diameter stretched piece (to get the look I wanted). I also remade the right side axle plate section (running a disc instead of a drum brake set-up). I have some pictures in the "Project Build" section under "J-Factor" chop. I don't remember if I had any good frame shots. The build is now in final break down, so if you need a pic or two let me know.

Aloha

[gasketscraper]

I think they went to a disc brake somewhere in those years. I can't remember exactly, but I put a square tube swingarm off a later model on my '76 XLCH, so I could run a disc brake and smaller diameter sprocket. So that might be the reason for the difference. I'll be interested to find out what the deal is on this one. I'm thinking of doing a hardtail bobber.

[ghostrider 61]

Sportster Homepage says that single front disk was available in '73, dual front disks in '77, and disks front and back in '79.

[BIGJIM]

73' to 77' Sporty and Superglides had Kayaba front ends, "Slice of pie calipers".