1941 Bent frame

[Steve Little]

Hi.
As some of you might know, I have a passion for Big Twin frames and I am always on the hunt for accurate information on them.
I went to the Wauseon swap meet last weekend and saw so many HD frames for sale....in fact the most I have ever seen at any swap. Some were only good for a couple of components but most were nice to very nice condition.

I was offered one of the early 1941 "bent" frames.
I have never had the chance to get up close and personal with one of these frames in bare condition.
I would like to see if I can get clarification on a couple of points on these frames...
1st point.
The owner said this "Bent" style frame was used late 1940 to somewhere in 1941. Anyone have any VIN range on this?

2nd point.
The factory bent the downtubes directly under the neck but these downtubes had a big curve in the middle of the downtubes "toward the engine" To me, it looked like it had been involved in a front end smash but the owner of the frame was addimant that this is the way these frames were supplied. The other pictures I have, dont have this bowed style of downtube but do have the neat little bend directly under the neck. Can anyone else elaborate whether these bowed downtubes were "Factory" supplied.

3rd point.
I have seen a picture of this style of frame before, but it had the 1940 style rivited tool box cross bar. This frame did not have any crossbar fitted but did have an original toolbox mount fitted.... although it is possible the crossbar may have been removed or fallen off in the past but the rivited bars usually stayed put.

I may have read a post on this forum a couple of years ago on how the factory bent this frame.
The writer indicated that the factory physically bent the frame after manufacture.
This frame that I saw on the weekend, and the other frame that I have pictures of, have a nice little pre manufactured bend in the backbone. The bend in the backbone does not look like the product of a physical bend after the frame was manufactured.
It looks more like a cold pressed, form bend
Also, the intermediate back bone does not have a bend to correspond with the dogleg in the backbone, and looks like it was fitted after the bent backbone was installed.
The owner of this frame also said he had personally seen a HD memo to dealers on how to "How to alter the earlier 25 degree 1940 frames" "OUT OF CUSTOMER SIGHT"
This proceedure involved a sledge hammer and block of wood.
Can anyone with good accurate knowledge clarify any of this.
Regards Steve

[RichO]

1940 frames

As to your concerns about 1940 frames. I have a 1940 EL that was a California Highway Patrol machine. The stock neck was 28 degrees. When they installed the new optional 16" tires for 1940 there was an unexpected handling problem. They solved it by bumping the top backbone bar, thus creating a 29 degree rake. The 1941 frames were produced with that amount of rake. The factory probally raked the necks that hadn't been built as complete machines to 29 degrees for the rest of that model year. Yes, the ones that were already sold did get bumped by the dealers in the manner of which you spoke. Mine was done that way. The front legs near the bottom of the neck head have ever so slight a bow to them. Remember 1 degree is not much but it worked. It does require shims and such to refit the speedo and it's housing to the top of the gas tanks though. That is only one of many unusual item on a 1940 machine. It was a major change over year and has older and newer designed parts in it's makeup. Hope this helps. P.S. I run the standard 18" wheels and it handles great.

[flat-happy]

hello steve---i bought the silver 1940 frame at wauseon with the 1938 fork and 1937 oil tank and dash backing plate from the guy in the wheelchair near the pavillion. it had the bent front tubes and i did read that memo many years ago but do not have a copy of it to post. i was also told at that time that the factory bent the tubes that way and if the dealer installed the optional 16" wheels that the dealer did it at the backbone not the front tubes and the factory put in 1/8 in longer tubes during manufacture and curved the front tubes till it had a 29 degree rake. i bought a toolbox mount for my 47 from you and asked about the backbone tube but you didn't have any with you.

[Jerry Wieland]

Steve I've talked to you before about those early 1941 frames. I do believe as you stated that the front tubes were straight from the sidecar loops until just before they enter the head casting and there they have a sharp short radius bend to correct the angle. I think if the front tubes are curved other than that it is because it has been in a wreck. No proof but just recalling the only original early 41 bike that I have ever seen.

Speaking of that bike - does anybody recall who owned that early 1941 knucklehead. It regularly showed up at the old Le Mars, Iowa AMCA meet and I believe was from that central states area. The guys' dad had owned it for years and maybe from new. Very original and low mile bike.

I find it hard to imagine what kind of tooling it took to 'pull' these frames once they were made and not distort the whole thing. I think that the frames were assembled with the parts already bent - just my opinion.

Jerry

[RichO]

bent

They may have been made like that as I stated after they saw the need, but the ones that already had been sold had to be bumped as mentioned. I've seen more than just mine. The top bar is bowed down and the front legs have a gentle bow forward. Riveted toolbox cross mount. Matching 40 barrels, heads, cases, trans, to match the frame. Knew the owner for 30 years and the owner before that. I've had it 10.

[Jerry Wieland]

Here are 2 pictures of the 'induced rake' frame that I have. First off understand that this frame was chopped but nobody is going to convince me that his kind of bending was done by a guy with a maul and a piece of wood. I had heard that story once to but have never believed it. My thought is that very few 1940 era shops were capable of this kind of work.

A triangle is the strongest geometric object there is to distortion and look what was done to the triangle formed by the neck, downtubes and the backbone on this frame. That took special tools and he-man strength.



Rich - do your downtubes have this much curve to them.



Jerry

[RichO]

bent

That frame may or may not be a 1940. The bow (front legs) is in the wrong direction for one thing. If you bowed the top tube to make the neck rake out on it's bottom side the legs would be bowed out not in and that top back bone tube has been beat with something. Mine has just a slight bow in it (legs too). Remember your only raking it one degree. I used to have a shop that I built frames and restored them. I know how tough a triangled frame can be. The frame in the photo looks like it has exchanged a lot of energy at one time or another. That means it been smacked good by something larger than itself. Only my opinion.

[RichO]

bent

Jerry, After looking at the photo again real hard, check this out. I believe it was hit dead on on the front legs and that bent the neck down some and then they bent it back up and left the legs bowed. You cAN SEE HOW THE THE TOP TUBE AT THE BACK GOES DOWN THEN UP. THE TOP OF THE FRONT LEGS ARE BOWED AND THE GO THE OTHER DIRECTION RIGHT UNDER THE NECK CASTING. This thing has been smacked and doesn't look anything like what a 1940 bumped frame would. Hope this helps.

[Jerry Wieland]

Rich My frame is a 1941 not a 1940 because it has a battery grounding tab and because of some of the parts I got with it. I have looked at an original paint 1940 EL serial number 40EL50xx and it did not have the mods and it had to have been made on the last week or so of production - it also had the ground wire still going to the oil line. I have never seen a 1940 frame that had any alterations to them and I have seen a lot of them although not to say that a few did not get done. 1940 was the 1st knucklehead I ever owned so I have been very watchful of them for almost 30 years. I know of probably 15 original type 1940 bikes and none has been stretched to 29 degrees.

I had always assumed that my frame has been poked in the nose and have really looked for these types of frames in good condition so I could see the profile and fix the front tubes. The backbone has not been beat with anything - that is the remains of bondo that some one used to smooth in a peanut tank and the profile of the tube is actually very round with no 'gorrilla marks'. I assume that maybe the top bend has been accented due to a hit but that pipe was never straight after it was made into a frame - it came that way.

I have an extensive collection of 1930's and 1940's (but not all of them) shop dope and not once is anything ever mentioned about redoing 1940/41 bike frames in the field. I understand that maybe it was a sensitive subject but there are other things in shop dopes that are that same way and sometimes the dealer is even warned not to make things known to the general public. Maybe he who bitches loudest gets the most satisfaction.

On your bike how did they readjust the dash to fix the tanks. I think in 1941 they used special length dash base mounting bolts. I have some old time NOS bolts that are 3/8" hex instead of 7/16" and are a different length and that is the only explanation I can come up with for them.

Jerry

[RichO]

bent

Jerry, my bike came w/36 tanks and shifter and shiftgate attached (but 40 dash shroud). I installed 40 tanks. I just used some shims to get it properly adjusted. The stock studs were long enough. I'll look and see if i have a photo of my frame after it was painted so you can see the bow. I'd have to send it to you but let's see if I can find one first.

[knuckleheadtim]

I've seen about 15 of these frames over the years and they all looked exactly like Jerry's pictures. These are undoubtedly factory bends done before assembly because the are so clean, and because the tube under the backbone needs to be longer to accomodate the rake. The triangle wouldnt allow the frame to just be bent out.

I saw one of these frames sell fo peanuts at Stafford Springs about 20 years ago because everyone thought it was tweaked. I've also seen them ruined by someone trying to "straighten them".

[exeric]

I have nothing to contribute to this thread other than to say, it's one of the most interesting topics I've seen on the forum for awhile. It's fasinating to hear from people with empirical knowledge and numerous samplings about the 1940 frame. I've heard all the folklore and B.S. so it's great to hear more substantial, and authoritative information.

[Jerry Wieland]

Steve

Is this the frame at Wauseon that you had questions about? I down loaded this from harleyson's site



I do not believe that this is 1941 - at least from this angle the back bone does not appear to have that little bend and it would have to have to be a 41 because that is the 1940 and down neck. To be a 1941 this frame would also need the frame mounted battery ground tab. I think this just might be a bent 1940 frame. It would be nice if anyone else had better angle pictures of it.

Jerry

[Steve Little]

Hi.
Appologies for the late reply. I just arrived back in Australia.
Hi. Jerry. That second picture that you supplied is not the frame that was offered to me at Wauseon. The guy that offered this frame to me had it in the back of a truck. The only bracket that was missing was the bottom half of the top engine mount. The front down tubes on this frame were bent inwards like your first photo on the first page of this thread.

Richo.
I think you may be quoting the Palmer "How to Restore" book when you say the 1936 to 1940 frames are 28 degrees.
The book is wrong, and it has everyone quoting the wrong degree.
These 1936 to 1940 frames are 25 degrees.
I have no idea of the true rake on these "Bent 1941 frames as I have never had one in my factory to measure it. But for the time being I will call it 1941 Bent frame.

The early 1941 frames used the 1940 ONLY neck which has the XE-35 in 1/8 font on the left side and the Foundry mark followed by a 6 in 1/8" font on the right side.

When the guy who owned this frame said that the downtubes should have the inward bow, as well as the neat little bends directly under the neck, I sighted past the 2 downtubes and they were perfectly level. Not the norm for a front end accident.

The backbone of the factory manufactured 1941 "Bent frames" looks to be cold pressed.
There are 2 bends within 4 inches and the tube has a 1/16" wall. This presssing would require a bit over 1000 psi This is based on what my 100 ton requires to do some of the pressings in the parts we manufacture.

The bowed in tubes were confusing for me as well.
But after 14 hrs "on the plane trip home" to think about it, my hypothosis as follows.
The backbone pressing is to increase the rake.
This also pushes out the downtube angle which is why the factory put the little bends in the downtubes directly under the neck.
This little bend gets the down tubes back in the general direction of the sidecar loops but not the right angle to slip back into the spigots of the sidecar loops.
The swoopy bends must be to bring the tubes back to the correct angle to enter the sidecar lugs.
If anyone has an interest in discussing any other frames from 1937 to 1969'm looking forward to getting back to the Davenport swap in 6 weeks.
I am looking for factory frame Blueprints for any frame from 1941 though 1947.
Regards Steve

[Steve Little]

I would like to clarify if the owner of this frame was correct in his information on these "Bent frames" being used in the late part of 1940.
Previous to this, I had never heard anyone make this claim and would like to get clarification, if its available.

Also has anyone seen these frames with the 1940 toolbox cross bar and without the rivited toolbox cross bar.

Regards Steve