Topic: Does this look right?- frame welds/bracket

[Dime]

Just noticed this on the frame after I started reading HondaMan's book and he mentioned poorly welded frames.

It almost looks like the piece of metal (bracket?) that wraps around the front of the neck had been cut. Also to me it doesn't look like the weld is done properly going up the tube leading to the neck. The other side has weld completely traveling up the tube towards the neck.

What are your thoughts? I could be over thinking this.

[Dime]

Should be a better picture

[MauiK3]

doesn't look right

[Dime]

doesn't look right

Dang it. My thoughts too.

[69cb750]

Looks like a frame repair.
A plate under tube or the tube.

[RAFster122s]

That rust is likely through crack in paint I bet. Something definitely is sketchy.

[bryanj]

Looks like a cheap "rake job" to me

[BenelliSEI]

That looks like accident repair that failed (or was never fixed). I’d find a piece of long pipe that fits tightly through the head stock and start taking measurements. I’m thinking it will be bent off to one side………

[Dime]

Quick video I did.

[RAFster122s]

Frame has not been raked or the stock pressed steel piece would have filler between headstock tube your triple trees stem mount into...

John's ideal on putting a pipe through your headstock is a good one. You can take precise measures to find if the frame is tweaked due to a wreck...or someone not stopping for a curb.

Where is the horn mount?

[Dime]

Frame has not been raked or the stock pressed steel piece would have filler between headstock tube your triple trees stem mount into...

John's ideal on putting a pipe through your headstock is a good one. You can take precise measures to find if the frame is tweaked due to a wreck...or someone not stopping for a curb.

Where is the horn mount?

It never had a horn so I have no idea.

I am getting my hands on some centering cones and will use threaded rod as my guide. Tried to get a piece of pipe to match the inside of the neck but everything was too big or small. Centering cones will do the trick.

[Dime]

Found a picture of another 78 cb750k frame and the bracket for the horn looks to be what was cut off on mine.

I have centering cones on route to check the neck. It might not be as bad as it looks from what I am seeing online pictures wise of other frames.

I will never regret checking this out all the same.

[BenelliSEI]

Found a picture of another 78 cb750k frame and the bracket for the horn looks to be what was cut off on mine.

I have centering cones on route to check the neck. It might not be as bad as it looks from what I am seeing online pictures wise of other frames.

I will never regret checking this out all the same.

I think you’d right, maybe someone ripped it off? If you weld it shut, drive a piece of steel in there so the weld doesn’t draw the headstock to the opening.

[Dime]

Found a picture of another 78 cb750k frame and the bracket for the horn looks to be what was cut off on mine.

I have centering cones on route to check the neck. It might not be as bad as it looks from what I am seeing online pictures wise of other frames.

I will never regret checking this out all the same.

I think you’d right, maybe someone ripped it off? If you weld it shut, drive a piece of steel in there so the weld doesn’t drown the headstock to the opening.

I am here sizing it up now.

What is remaining of the bracket looks to be held on by two spot welds. I think I will drill out the welds, remove what is left of the bracket, and grind it flush.

What welding that needs to be done isn't a big deal. It needs a bead run down by the tube and another bead by the plate.

That is all providing the neck proves to be strait.

The cones I have coming are made to accept 3/4" threaded rod. I will use a 36" piece of threaded rod and sit it on two pieces of wood like I have the frame sitting on. This should give me a solid point of reference.

[Dime]

The machined cones finally showed up after the postal strike. Grabbed a length of 3/4-10 threaded rod, nuts and washers and set it up.

No issue with the frame. Measured from multiple points and it is not out. Very thankful.

[Don R]

  Check the rest of the frame for rust and freeze damage, often they need repair around the sidestand bracket weld. I replaced that entire tube on one bike, your repair won't be so bad. If it had been extensively modified there would be more signs of it.
  Like John said, the bigger the gap, the more tendency it has to pull. It is rather curious, that should be one of the more ridged parts of the frame you wouldn't expect it to flex much.

[Dime]

  Check the rest of the frame for rust and freeze damage, often they need repair around the sidestand bracket weld. I replaced that entire tube on one bike, your repair won't be so bad. If it had been extensively modified there would be more signs of it.
  Like John said, the bigger the gap, the more tendency it has to pull. It is rather curious, that should be one of the more ridged parts of the frame you wouldn't expect it to flex much.

Don,

I checked out the rest of the frame, surface rust only, no holes or cracks. I will have it sandblasted and either paint or powder coat just to freshen it up.

[Don R]

 Mine was an early frame that didn't have the drain holes drilled in it. Your frame isn't really that bad except the one odd spot. I'm probably guilty of over-welding a few of those spots that a smart engineer thought shouldn't be, or at least didn't need to be welded.

 I always remember there were engineer decisions and also bean counter decisions. For example, the brake lugs cast into the right fork tube, I always contended the engineers wanted double disc brakes, but the price point didn't allow for it.

[Dime]

Mine was an early frame that didn't have the drain holes drilled in it. Your frame isn't really that bad except the one odd spot. I'm probably guilty of over-welding a few of those spots that a smart engineer thought shouldn't be, or at least didn't need to be welded.

 I always remember there were engineer decisions and also bean counter decisions. For example, the brake lugs cast into the right fork tube, I always contended the engineers wanted double disc brakes, but the price point didn't allow for it.

I don't subscribe to the idea that the manufacturers engineers got it 100% right out of the gate. Like you said though, where mine is the last year of production I would say most of the kinks were worked out by then.

It took guys racing and modifying bikes to see where the weak points are.

I can't see any particular weak areas on my frame. That being said I am just going off best guess as well.

[Dime]

I came across an old post about drain holes in 7/32" size supposed to be on the bottom side of the frame just behind the engine boss. Mine doesn't have them. Just wondering if I should add them?

[Don R]

  I doubt that a hole or two that small would hurt, there was a bulletin about adding them to the early frames. Honda left vent holes so welding pressure didn't build up in the frame and blow the molten metal out.
 We do the same on chrome moly race car frames now except we hide them inside a fitted joint. I helped front half a funnycar chassis that always leaked oil, the top frame rails transport engine crankcase blowby to a tank in the back, somewhere the builder drilled a vent hole between the top rail and the rest of the frame. We found it in the front half and eventually it stopped dripping oil.