SOHC CB750 Engine Install Stand

One80Auto

Active Member
I've had a couple of requests in my build thread (link in sig) to post up some rough measurements and ramblings about an engine install stand I cobbled together from some scrap metal. I know it looks strange but it works, so just humor me. Exhibit A:

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Which allows me to go from this:

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To this, in about 20 minutes without lifting anything heavier than the frame:

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I know there are some proven ways to get this done for this historically tight frame but none appealed to me. I have done the "place the bike on its side" method that seems be the most popular and it is doable....but.....I thought it would be easy enough to come up with something that had a mechanical advantage in the interest of hernia prevention since I am always a one-man show while working on this thing. The typical disclaimer applies: I have a mechanical background but I am no structural engineer; if you are cutting, drilling, and welding metal in order to support another 200 lb. lump of metal without taking a moment to think about what you are doing, there is a good chance you might need a band-aid or in the very least get your feelings hurt. Please be careful. So here we go.

Why?
-My build is going to require a multitude of complete mockups and teardowns (again all solo).
-I wanted to embarass myself with some truly piss-poor arc welding.
-I wanted to practice fixing warping due to aforementioned piss-poor welding using improper OA torch technique.
-My body type is what is known as "wiry" (a.k.a. skinny, a.k.a. lazy)

Some limitations this thing has that I have picked up on so far, and I'm sure the experience level on this forum will identify some others.
-It is not adjustable height-wise....YET!
-The carbs have to come off.
- Lacks mobility for moving the engine to/from a complete bike as opposed to my current method of bringing the frame to the engine. Easily fixed with more adjustability and some castors I suspect.

So here is how it goes basically. I start with the engine on its overhaul/storage stand that uses only the two lower engine mounts which is key to this whole idea (another pitiful weld project).

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Slide the Install Stand on the backside:

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To be continued in another post, just give me a minute or two. I've been burned before on large posts disappearing before I could push the submit button.
 
NEXT!

Okay so now comes the hookups. Notice as you look through this next bit the stand grabs the engine from the top mostly in the center to allow the frame to come in. Three attachment points that won't cause damage to the frame or a nicely finished engine are as follows.

1.) Front right upper mount:

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2.) Strap around the stator cover:

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3.) Strap threw a left over engine mount bolt with the threads removed so they dont cut into the engine casting. It is sitting on a cheap homemade cam. Which is just a bolt welded on there so when the screw is tightened down it lifts up the backend of the engine to relieve the weight off of the overhaul stand.

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Adjust the ratchet strap around the stator cover for level so the load is distributed evenly:

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Remove the two lower engine bolts:

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There is some famous adage about a lever and the world that I can't remember right now but a long lever allows me to tilt the engine a couple of inches so I can slide out the overhaul/storage stand:

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Okay, one last post and this tragic novel will be complete.....STANDBY!
 
Okay readjust for level if needed. My stand doesn't flex much but I do check it. You are left with something like this:

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In comes the frame:

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For posterity sake here are some places I threw tape on to indicate the common areas that get beat up during the exercise of "sliding" the frame into postion. Kind of reminds me of the game "Operation" I played growing up:

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Reinstall the two lower mount bolts to suspend the frame:

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Use the lever thing again to slide the work stand of your choice under there, release the install stand hookups in reverse order, slide it away and off you go:

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So there it is. Works for me, won't apply to some but it is an option and I figured it was time to give something back to a forum that has provided me with alot of information and inspiration. A couple of miscellanous notes...I used 14 ga. 1 1/2" square tubing for the install stand and some 14 ga. 1 1/2" angle sprinkled in for the overhaul/storage stand. For the record I hung about 400 lbs. worth of weight from the stand for about 5 days right after building it. I had a tape on it to measure any flex and it was not painted yet so I could inspect for cracks or failing welds under load and the thing barely budged. Good enough for me. I hope somebody finds this useful. Novel Complete!
 
OpTiCz said:
are you selling stands?

Sent from my HTC Glacier using Tapatalk

No Sir, just posting the info up for some guys that requested it.

Forgot to post up measurements....standby for yet another post.
 
One80Auto.

Thanks for posting this thread.

For all the guys that can't or won't build one....if you could figuire out a way to have them produced I think you could make a nice roll of cash for your build.

I currently have my engine on a Typical engine stand adapted to the CB750 engine rear mount points. This is nice because of the work height and the ability to rotate the engine 360 degrees to detail and paint the bottom, but after rebuild/refurb a stand like this would be great to have for install. (I too work Solo alot). Do you think it could be modified to be used in conjunction with a Motorcycle lift like pictured below?

*Base on wheels/castors?

*Base wide enough to fit around base of lift during insertion? (Actually yours would be wide enough as designed since the my lift is 14" wide on the ground)

*Built at a height that is in the lifting range of the motorcycle lift?


1) Adjust the height of the lift to accept the static height of the "Install Stand" for insertion.
2) Roll the engine over and insert/push engine into the frame.
3) Jack the lifts height to seat the engine in the frame.

This way nothing has to be manually handled and could be used on a fully built/dressed CB750.

Your "work stand" could then also be built to a height that mates with the "Install Stand" transfer. Perhaps even at a height that is transferable back and forth from the "Work Stand" to "Install Stand" with the "Work Stand" on a second motorcycle lift in it's fully down position. This way once the the transfer from Install stand to work stand is complete the engine mounted on the work stand could be lifted to a more work friendly height.
 

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Frankenfe, all your points/ideas make sense. I will actually be forced to modify the stand at some point when the bike is done for use on a complete bike. I'll tinker around with the design at that point. I literally built that stand around the engine. I'll do the same when the bike is complete to make sure it actually works. It will be a bit though.
 
Thanks a lot for posting this man. This stand is probably the coolest idea for us 750 nuts I've seen in a long time!
 
Reading your post about the SOHC engine lift - I am extremely interested in reviewing what you did - but there is a problem.
I cannot view any of the pics because they are hosted in photobucket - and they want me to buy/purchase membership in their programs with X amount of storage - and I do not need any of that...
All I want to do is view your pics........

Is there another way to view what you accomplished - without paying photobucket $400?
I'm a one-man-band too... and I'm a 68 year old retiree who cannot afford what they demand just to view your pics.

Aubrey
AK Engineering
akengineering@live.com
 
That is a really nice stand and well documented. Thanks for that.

Rodaroo, check on line for a fix that allows you to see photobucket pictures. It's a simple patch.
 
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