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I had thought about that, I've actually got a foundry and could cast them myself, but I couldn't figure out how to tap the tappet cover holes, I mean, I could figure it out, but it would involve a shit ton of money to make or buy a large tap, so it was that or redesign the tappet covers to use machine screws, I'll try welding for now and if it's not the right way to go, consider other options
You could try casting the lugs onto your existing rockers if it's a bit shitty to weld. You'd have to clean it up well and heat it up so not to crack. We used to do that with even cast iron on occasion, You have a bigger joint / contact area compared to a welded piece too.

Bed the rocker into moulding sand and make a pool around where you need the lugs. Get some heat into the mould with a propane torch and it should work ok. Any contaminants in your existing casting will vent to the surface, so you would require tabs far longer than you actually need, so that when you cut them to length, you're into clean metal. May be worth running a small riser at an angle from the bottom to help vent and get some flow across it.

If you bed it well enough on the underside, you won't have problem with burning through.
 

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Get a laser cutting guy to scan the base of the rockercover to make a 6.0mm high tensile steel or chromoly sheet 'gasket' to bolt between the rocker cover and the head to use as a headsteady to the frame. The design is up to you. You would not be able to use a mechanical tacho, but that's the only functional issue I can think of. You would be using two gaskets, obviously.

valve%20cover%20(2).jpg

Danger, is my business."
 

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Get a laser cutting guy to scan the base of the rockercover to make a 6.0mm high tensile steel or chromoly sheet 'gasket' to bolt between the rocker cover and the head to use as a headsteady to the frame. The design is up to you. You would not be able to use a mechanical tacho, but that's the only functional issue I can think of. You would be using two gaskets, obviously.

View attachment 12961
that is not awfully bad idea.
 

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If you add 6mm plate between the cover and the head you'll want to add 6mm to the knubs on the valve cover (in line with Tach gear. those are rocker oilers (well really splash redirection) to keep valve springs covered in coolant (oil)
 

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If you add 6mm plate between the cover and the head you'll want to add 6mm to the knubs on the valve cover (in line with Tach gear. those are rocker oilers (well really splash redirection) to keep valve springs covered in coolant (oil)
That's probably a Ge__t_ question regarding oil splash control.

Not hard to stick on some plastic extensions with epoxy. Even some pieces of reed valve maybe.

Personally, I don't think it would make any difference. Valve springs and valve guides only need a bit of oil flow and mist. The cam and followers are a different matter, and need a little flow and full buckets.

Danger, is my business."
 

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finally getting around to starting the frame for my cb750, "sketched" it out in 1/4 rod, any thoughts? the top tubes are going to be 1-1/4" along with the two tubes going down to the front engine mounts, the rest will be 1", the black foam is where mounts will be welded to the valve cover. the subframe will either be aluminum tube or possibly carbon fiber, in which case the whole seat/tail section would be one piece of carbon. the swingarm will possibly be connected to the shock through a linkage where the shock is mounted to the underside engine mounts

View attachment 12736
I haven't even read all this thread, this is cool.

Couldn't you have about a 10mm thick or whatever plate of aluminum cut with a water jet?
if you shape it right it might be awesome! the inside shape you are stuck with, but not the outside.

? What tubing are you going to use in the finished frame ?
 

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No matter which way you do it, you still have to account for expansion and contraction. I know it's your time and your money, but at the end of the day, you need to ask yourself what it is that you are expecting from this mount. If you have to allow for movement of the head and barrel etc, then the frame has to be strong enough to survive without this mount and not count on it as a load bearing member. In the end, all you are ending up with is a glorified head steady. It'll make a great conversation piece, but is it worth all of the effort? I know I'm a little different, but I would be more inclined to keep the first frame relatively straight forward based on proven designs. Put the energy into a decent jig that you can also use to straighten the frame out once you're done welding.
You can do things like change cylinder studs to add strength, but then you are taking away their ability to expand and contract along with the aluminum bits. This will likely lead to head and base gasket problems.
 

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No matter which way you do it, you still have to account for expansion and contraction. I know it's your time and your money, but at the end of the day, you need to ask yourself what it is that you are expecting from this mount. If you have to allow for movement of the head and barrel etc, then the frame has to be strong enough to survive without this mount and not count on it as a load bearing member. In the end, all you are ending up with is a glorified head steady. It'll make a great conversation piece, but is it worth all of the effort? I know I'm a little different, but I would be more inclined to keep the first frame relatively straight forward based on proven designs. Put the energy into a decent jig that you can also use to straighten the frame out once you're done welding.
You can do things like change cylinder studs to add strength, but then you are taking away their ability to expand and contract along with the aluminum bits. This will likely lead to head and base gasket problems.
He's trying to out-engineer the best, and reinvent the wheel. It is a waste of effort to make a load bearing sohc CB750 head mount.

I hope he goes ahead. He will learn plenty, after making close to ten frames, before one works well.

The funny thing is if the OP took about 30% of the advice from experienced guys on this thread, he could easily build bikes far better than Sadiago Choppers café efforts and that shop that 'builds' café racers to sell Oriental junk parts.

Danger, is my business."
 

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Discussion Starter #70
the head mounts will move about .020", which is significant, but is also well within the normal range of deflection of the loaded frame, the whole reason I want to use the head as a stressed member is to create a more rigid neck, and keep the swingarm pivot and neck in better alignment, I don't see many steel frames that use the head this way, but I see it a lot in aluminum perimeter frames, if you look at the rod sketches, the head mounts create two bases to triangulate the bottom neck mounts, shortening the effective length of the stressed section of the tubing and giving a better rigidity, providing of course that the head will bear the load. the head isn't bearing the entire load of the neck though, and the neck would be well supported even without the head mounts, so there's a redundancy to the design. we'll see if the studs are sufficient, my assumption is that they will be fine, they're 5/16" stressproof rod (x16) and torqued, so there's a lot of force holding the head down, whether or not the frame will flex it enough to unseal the gaskets is indeed a question, so we'll have to see. I see witless is posting quite a bit, and my guess can only be that he's posting some cool pics of the bikes he's working on?
 

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Does it not make sense to put aluminum between 2 pieces of aluminum.
and if it's not being designed solid to the frame,
would you not rubber mount to this part if you wanted to isolate it from the frame ?
… or maybe put a control arm on it and use it to transfer some motor torque forces ?



& Wit , I make no apologies for having a real life.
 

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Discussion Starter #72
I'm not designing it to be isolated from the frame, but the amount that it expands is a very small amount, the crankcases expand quite a bit as well, but as you can see, Honda didn't design the lower engine mounts as rubber isolated, steel is quite stiff but any frame design is going to change shape under load, and that change in shape doesn't mean it's compromised as a load bearing structure. bridges move quite a bit but you still expect them to hold up the roadway
 

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the head mounts will move about .020", which is significant, but is also well within the normal range of deflection of the loaded frame, the whole reason I want to use the head as a stressed member is to create a more rigid neck, and keep the swingarm pivot and neck in better alignment, I don't see many steel frames that use the head this way, but I see it a lot in aluminum perimeter frames, if you look at the rod sketches, the head mounts create two bases to triangulate the bottom neck mounts, shortening the effective length of the stressed section of the tubing and giving a better rigidity, providing of course that the head will bear the load. the head isn't bearing the entire load of the neck though, and the neck would be well supported even without the head mounts, so there's a redundancy to the design. we'll see if the studs are sufficient, my assumption is that they will be fine, they're 5/16" stressproof rod (x16) and torqued, so there's a lot of force holding the head down, whether or not the frame will flex it enough to unseal the gaskets is indeed a question, so we'll have to see. I see witless is posting quite a bit, and my guess can only be that he's posting some cool pics of the bikes he's working on?
You are not even 1/4 the way into frame Mk1.

Plenty of guys give you good engineering advice, and then you procede to talk to yourself and justify illogical notions.

I've completed all MY chassis, BTW.

Danger, is my business.
 

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Im a little late here.
REALLY love that people are doing interesting things and talking about them here.
But as is the new norm here, WW and TR are locked in an epic battle.....


Personally I can not see using the stock cam cover in any meaningful way.
Take a look at the old RC Engineering cam covers.
Yes that was to solve a different problem, but might give you an idea.
 

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Im a little late here.
REALLY love that people are doing interesting things and talking about them here.
But as is the new norm here, WW n __ are locked in an epic battle..
I'm not locked in battle. I'm just swatting away a fly.

Danger, is my business."

P.S. There is more truth in that statement, in real life, than you imagine.
 

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the head mounts will move about .020", which is significant, but is also well within the normal range of deflection of the loaded frame, the whole reason I want to use the head as a stressed member is to create a more rigid neck, and keep the swingarm pivot and neck in better alignment, I don't see many steel frames that use the head this way, but I see it a lot in aluminum perimeter frames, if you look at the rod sketches, the head mounts create two bases to triangulate the bottom neck mounts, shortening the effective length of the stressed section of the tubing and giving a better rigidity, providing of course that the head will bear the load. the head isn't bearing the entire load of the neck though, and the neck would be well supported even without the head mounts, so there's a redundancy to the design. we'll see if the studs are sufficient, my assumption is that they will be fine, they're 5/16" stressproof rod (x16) and torqued, so there's a lot of force holding the head down, whether or not the frame will flex it enough to unseal the gaskets is indeed a question, so we'll have to see. I see witless is posting quite a bit, and my guess can only be that he's posting some cool pics of the bikes he's working on?
With regards to leaking gaskets, I wasn’t only referring to the added stress by placing a mount there. There is also a potential problem if you replace the existing studs with stronger ones, should you eventually decide to go that route. I suppose the proof will be in the pudding and it will all depend on how much you are asking of the head mount. Although the stock studs seem fine for their current application, I think they would be borderline for your application (again depending on how much additional stress you apply to them). Honda went to a different style of stud in the auto world around that time and then started using the new style in early CBX’s. The cylinder studs need to be able to take up the expansion and contraction of the aluminum bits without losing their torque. Too strong and they will compress the gaskets to the point where they will eventually leak or the studs will tear out of the cases. Too weak or unable to return to their original length and the head nuts lose their torque.
 

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Agree there is no battle here, I'm just trying to keep it real.
maybe even help some.
I can't see any down side to adding a little mass to it
and providing considerably more rigidity in an area of the frame that will see some very tremendous stress and vibration,
more places to bolt to, sounds pretty cool to me.
 

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If you seriously want to do this, cast your own valve cover with the mounts in it. Don't waste your time pissing around with sandwiched plates and all that crap.

You've got 18 M6 bolts holding that sucker on. You aren't going to rip it off.

You also still have the two rear engine mounts and the front downtube mount, so it's not like you're hanging the entire engine off the valve cover.
 
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