51 mid-year changes?

[bmh]

Hi,
Does anyone know at what point in the 1951 production year the factory switched from the 3 rib fender to the 1 rib fender? Photos of the 51 prototype show a 3 rib and a photo of an actual production line police model shows a 1 rib. Can anyone say for sure when this change was made? Also would anyone know at what point in production the threads on the horn mounts were changed?
Thanks, Brian

[exeric]

I have a late production 1951 FL and it has the wide 3 rib rear fender. H-D changed the fender in 1952 because the wide flap had a tendency to rub on the tire. I know of the picture you have mentioned but that is on a police bike and that's a whole different animal. The fender was trimmed to permit access for the siren tire roller. If you are putting together a civilian '51 then the 3 rib fender is correct. As for the horn screws, Bruce Palmer say #10 screws were early '51 and #12 screws were late. AMCA judges are not permitted to remove hardware to check for thread pitch.

[bmh]

Thanks Eric,
Does your 51 have its original sheet metal? I realize police bikes have quite a few differences. I have also seen photos of 49 police bikes with 3 rib fenders, with an oval hole cut in for the siren drive. and my thought on the horn mounts is that a #10 and a #12 will have diferent size heads,right?
Brian

[exeric]

My '51 sheet metal is all genuine and original. The bike was a chopper when I got it but among the few original parts was the rear fender section. As I stated, I have never seen a civilian FL or EL with the '52 and up rear fender. Regarding the horn screws. If you notice in Palmers book, the hex size of the horn mounting screw does not change, only the the thread size. It looks to be a 7/16" or 1/2" hex. I don't know because I used hardware store 10-32 screws to mount my horn. I know someone like Colony or Competition Distributing is reproducing the horn mounting kit. Tell me how far along you are with your '51.

[bmh]

Not very far along. Do not have a frame or sheet metal yet. Still sorting out what I have and going through my collection of parts looking for anything that would be correct, so I am still gathering parts and doing some research.Built lots of bikes but this is my first attempt at a restoration. I figuire that any time spent on research at this point will be well worth it as opposed to changing out parts when I'm done.
You say yours is a late 51, if I may ask, How late? I am working on 51EL72XX , wich puts me in the last 2000 units produced, is yours later than that?
Again thanks for your help, Brian

[exeric]

Mine is 51FL60xx. As I stated, it was a chopper when I got it, but it was done in the days when radical meant raking the neck and cutting off superfluous brackets and mounts. The guy kept a lot of the genuine stuff but it was really beat. Florida is hell on sheet metal. I know this bike was originally bought in Orlando at Puckett's Harley Davidson and spent it's whole life in central Florida so it didn't make the swap meet rounds and was defiled by just one redneck bozo. In the past, I had tons of HydraGlide stuff but most of it's gone now. I would like to help you with anything I can becuase I love 48-51 hand shift big twins.

I think Panheads are still reasonably affordable to restore, and certainly well worth doing. You should be able to do a '51 out of parts without too much difficulty and if you get stumped on genuine parts you can always go to aftermarket. However, I would urge you to spend the extra buck, and time to find genuine H-D parts. The real stuff always fits.

My '51 is getting long in the tooth and I have penciled it in for a complete overhaul. Over the years I have been socking away the odd ball stuff that is particular to a '51 so when it does come down it will go back correct. Keep us posted on how you're doing.

[bmh]

Thanks for your help , I'm sure you'll see me make some future postings here as I go along.
Thanks again , Brian

[framemaker]

Hi. My unrestored 51FL 91XX has the single stengthening rib. This bike is all original.
Transition bikes can be interesting.
Regards Steve

[bmh]

Steve,
Wich horn mount blocks are on your frame? And thanks for confirming my suspicion that some late 51's had the single rib fender.
Thanks, Brian

[framemaker]

Hi Brian.
The horn blocks are square ended and have 12x24 tpi. This flies in the face of the Palmer book. The Palmer book is a great book, but it is not the.... be all, end all... of accurate information.
Looking at the burgandy bike in the above picture, my 51 is that colour as well. I guess it was a popular colour of the day. Who ever painted my bike the first time, painted it orange over the original blue. He must of been one of those "stand out kinda guys"

[jwl]

FYI. Regarding the question on the proper rear fender for a 51 Panhead. I have an original paint 51 with only 600 actual miles. It has never been wrenched on and it has the 3 rib fender. Serial number is 51EL1392.

[bmh]

Wow , two people lucky enough to have all original 51's. I envy both of you. That horn block thing has bugged me for a while now.I couldn't find anyone I know who in all their years had ever even seen a original frame with a srtap toolbox mount and round horn blocks , and now I now why. I was also wondering if either of you gentlemen would be inclined to send me some decent photos of your bikes. I would like to use them for reference on my project . They would be a great help in cable and wire routing, hardware type and finish, etc. If you can do it please send them to me at brianapryl@verizon.net Thanks again, Brian

[framemaker]

Hi Brian.
You will get both ends of the spectrum. JWL's bike is only 392 from the start of the run and mine must be nearly at the end of the run.
I am happy to send you pictures of my 51. My wiring loom has never been off the frame "execept for the rear fender loom which must have been removed when past owner repainted the fenders " and it has all the original clips in place. My 51 and 1958 Pans are strapped to the rafters of my workshop. They look like Christmas baubles hanging up there. I needed the room.
I know of 2 more unrestored original paint 1951 Pans here in Australia. They must be as common as mud.
If you need either style of the horn blocks or any other part for your frame, I have them in stock.
Regards Steve
Race Frame Engineering