Author Topic: CB750 engine removal  (Read 6188 times)

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Offline mycb750k6

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CB750 engine removal
« on: March 31, 2010, 11:09:03 am »
I'm going to take the engine out of my CB750 K1 this week and am trying to decide how. I was wondering if anyone has used a block and tackle from the roof to help lift and support the engine while it is being maneuvered out. If so how and where did you support the engine. If you think this will work OK let me know. Likewise if this is a bad idea I'd like to know as well.

Offline Duke McDukiedook

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Re: CB750 engine removal
« Reply #1 on: March 31, 2010, 11:13:48 am »
"Well, Mr. Carpetbagger. We got somethin' in this territory called the Missouri boat ride."   Josey Wales

"It's Baltimore, gentlemen. The gods will not save you." Ervin Burrell

CB750 K3 crat | (2) 1986 VFR750F

Offline scroggins5000

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Re: CB750 engine removal
« Reply #2 on: March 31, 2010, 12:26:00 pm »
I'm going to take the engine out of my CB750 K1 this week and am trying to decide how. I was wondering if anyone has used a block and tackle from the roof to help lift and support the engine while it is being maneuvered out. If so how and where did you support the engine. If you think this will work OK let me know. Likewise if this is a bad idea I'd like to know as well.

Here are a few more options.
1) Work on your power thrusts, put a back brace on, and go to town.
2) Get a friend to help. This is the way I did it, because we needed to do it quick. Make sure to leave the kickstand on to have something to hold onto. It wasn't that bad...
3) Take the wheels, swing arm, and front forks off. Then lay the frame on its side and unbolt the engine, and lift the frame off the engine. Presto! Be sure to lay down some wood or something, so not too damage any covers. This is more time consuming, but if you're tearing down anyways its super easy.

Offline GammaFlat

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Re: CB750 engine removal
« Reply #3 on: March 31, 2010, 12:51:34 pm »
I've done what you're talking about (cable from ceiling).  I used three straps on the engine grabbing it at different points while I moved the engine always having at least 2 straps secure.  I used cheap harbor freight straps and they worked fine.  Some of the hooking points: Under the alternator AND under the points cover with one strap looping over the top.  Around the jugs.  Around the motor mounts upper rear (I think I put a bolt through to get more to hang on to). 

I did the whole thing myself and it was a breeze.  Just be cautious and patient.  Reposition the straps as you wiggle the engine out. 

Good luck
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Offline mycb750k6

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Re: CB750 engine removal
« Reply #4 on: March 31, 2010, 12:55:54 pm »
Well thanks for that but I'm old and feeble so a back brace won't be of much help.

I like the idea of lifting the frame off the engine but:
The engine comes out the right side so the bike would have to lying on it's right side but that means all motor mount bolts out. So I'm having a hard time imagining rolling the frame and engine over onto it's right side with no mounting bolts in with the engine flopping around in there without beating the crap out of the frame. Can it be done alone?

So that's why I thought if I just lifted it with a 5:1 block and tackle and then maneuvered it out the side onto a rolling dolly, I could do it by myself.

So I like the lift in post two above but that's way more work than I'm prepared to do. This is a one time deal - out and in.

Offline mycb750k6

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Re: CB750 engine removal
« Reply #5 on: March 31, 2010, 12:57:20 pm »
Thanks Gammaflat. That's what I was hoping to hear.

Offline scroggins5000

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Re: CB750 engine removal
« Reply #6 on: March 31, 2010, 01:54:17 pm »
Well thanks for that but I'm old and feeble so a back brace won't be of much help.

I like the idea of lifting the frame off the engine but:
The engine comes out the right side so the bike would have to lying on it's right side but that means all motor mount bolts out. So I'm having a hard time imagining rolling the frame and engine over onto it's right side with no mounting bolts in with the engine flopping around in there without beating the crap out of the frame. Can it be done alone?

So that's why I thought if I just lifted it with a 5:1 block and tackle and then maneuvered it out the side onto a rolling dolly, I could do it by myself.

So I like the lift in post two above but that's way more work than I'm prepared to do. This is a one time deal - out and in.

You would take out all the bolts except for the two long ones, and this method may require two people. If you have the equipment I say go for it the other way.

Offline bikerbart

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Re: CB750 engine removal
« Reply #7 on: March 31, 2010, 03:53:47 pm »
Put a milk crate right next to  the bike,perfect height for this,2 people and its not so bad.wiggle it out and set it on the crate.Quick and easy.
its better to regret something you have done,than something you havent.Except playing with explosives.

Offline GammaFlat

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Re: CB750 engine removal
« Reply #8 on: March 31, 2010, 04:41:12 pm »
How about this http://forums.sohc4.net/index.php?topic=58210.0?


Wow!  No kidding man, that looks great - I think I must have one :) 
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Offline 73nancy

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Re: CB750 engine removal
« Reply #9 on: March 31, 2010, 10:46:30 pm »
just pulled my motor in my k1 last night. i have removed it before using the lay down method worked but took some time. this time i just used one other person for help pulling the motor out the right side. at first i though it was going to suck. i undid all the bolts and let the engine just sit there since it was tightly in place. my buddy grabed the left i grabed the right. tiped the engine forward a bit and up and it slid right out. less than 30 sec of lifting.. worked so great i recomend this method if you have someone to help you.
k1 cb750 cafe racer (aka Helter Skelter)
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k3 cb750 race bike 911 big bore, alum rods, 13:1, race cam other goodies

Offline 76CB5WI

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Re: CB750 engine removal
« Reply #10 on: April 01, 2010, 03:02:39 am »
Without a doubt get a person to help you its so easy from there
you wont bung up your frame and the engine lifts out almost
effortlessly. The #$%* of the job is disconnecting all the peripherals
a PIA..the reason my retorque probably wont happen soon.
Its a time consuming stepwise project.
87 FJ1200
72 CB750
76 CB550

Offline mycb750k6

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Re: CB750 engine removal
« Reply #11 on: April 01, 2010, 04:05:22 am »
OK Thanks. My motorcycle friend is coming by after work. I have everything disconnected and removed except the wheels.
We'll just grunt it out as you describe. Then off to the painters and chromers. Man I'm going to need a lot of parts I hadn't planned on. I guess that's the way it goes. Looks like a greasy picked over turkey carcass.

Offline andy750

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Re: CB750 engine removal
« Reply #12 on: April 01, 2010, 04:47:28 am »
Make it easier on yourself by

1. Removing exhaust spigots.
2. Remove breather cover
3. Remove carb overflow tube tab at back of crankcase (if you have one).
4. Remove oil filter (although hopefully that should be obvious)

These small changes give you more room and engine should slip out easily.

Good luck!
Current bikes
1. CB750K4: Long distance bike, 17 countries and counting...2001 - Trans-USA-Mexico, 2003 - European Tour, 2004 - SOHC Easy Rider Trip , 2008 - Adirondack Tour 2-up , 2013 - Tail of the Dragon Tour , 2017: 836 kit install and bottom end rebuild. And rebirth: http://forums.sohc4.net/index.php/topic,173213.msg2029836.html#msg2029836
2. CB750/810cc K2  - road racer with JMR worked head 71 hp
3. Yamaha Tenere T700 2022

Where did you go on your bike today? - http://forums.sohc4.net/index.php?topic=45183.2350

Offline 73nancy

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Re: CB750 engine removal
« Reply #13 on: April 01, 2010, 09:51:03 am »
do work!!!!! just make sure you by your friend a beer for the help... also make sure you got something soft to but the motor on next to your frame.. moving blankets work great.. good luck...
k1 cb750 cafe racer (aka Helter Skelter)
k6 cb750 stock daily rider project
k3 cb750 race bike 911 big bore, alum rods, 13:1, race cam other goodies

Offline mycb750k6

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Re: CB750 engine removal
« Reply #14 on: May 02, 2010, 05:09:36 am »
OK this is what I came up with. Took five minutes about and no dents or scratches. Like most things, it's the prep.

Offline crazypj

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Re: CB750 engine removal
« Reply #15 on: May 02, 2010, 05:23:48 am »
What I used to do, remove all bolts, remove clutch cable, remove starter cable, reach through frame at front right then lift it out to balance on frame rail then front and rear lift onto bench.
 Its less than 220lbs, a bit of an award shape though

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Offline mycb750k6

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Re: CB750 engine removal
« Reply #16 on: May 02, 2010, 05:35:12 am »
Yeah, I'm 63 with an old back. That's not an option for me. I had my son do the heavy lifting - such as it was.

Offline MCRider

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Re: CB750 engine removal
« Reply #17 on: May 02, 2010, 07:23:24 pm »
Yeah, I'm 63 with an old back. That's not an option for me. I had my son do the heavy lifting - such as it was.
Even at my prime, early 20s, I couldn't do it by myself. Though I know of some that could.
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"Sometimes the light's all shining on me, other times I can barely see, lately it appears to me, what a long, strange trip its been."