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Engine removal & install.

matty

Border raider.
Joined
Feb 8, 2022
Member Number
139
Posts
648
Location
England Scotish border
As much as i hate to admit it, 64 years on this planet and perhaps equally negative a stroke last year have left me ....Compromised .. Some what. Or more to the point Too weak to lift a Larger 750 upwards engine out of a frame with the brute force bear hug and grunt method.
Being faced with the need to remove a 900 four from an old tube frame, left me feeling daunted. I did the old trick of lifting the bike with an engine crane slung off the engine, and removed the mounting bolts and moved the lighter frame around the engine until it was clear then rotated the frame past the engine sideways if you follow.
This was all well and good in this instance, as the bike was completely stripped to just frame and engine.
Now having managed this time, i am looking to now gathering tips and info on techneques diy tooling or inovations that will help me and probably others get this job done if alone or simply too old or lazy or perhaps just too sensible to manhandle big engines in and out of motorcycles.
 
I like your way the best. Stripped frame and away you go. I'm sure you could rig up some straps or something, or wait for a few buddy's to show up, but I feel like I could've pulled the forks and swinger off in that time.
 
In cases of engines small enough to manipulate into position, lifting the frame off the engine is always the easiest way. When I assembled my CL450 build I laid the engine on its side and laid the frame over it to avoid chipping my fresh powdercoat.
450assembly.gif
 
In place I once rented there was a simple beam and hoist setup (similar to the photo below, but slimmer and only for 500 kg) mounted on the back of the garage door metal framework. This worked nicely to lift bikes to work on. The owner had used it to lift engines out of cars he was working on. It was a bit limiting that it would only move sideways, not back and forth but it was much better than nothing.

2022-06-17 17_13_38-Window.jpg
 
Walk the engine up a ramp into the frame, then put a ratchet strap from the engine to the top tube.
 
Here's an old thread from SOHC4, there are plenty of pics still visible if viewing as a guest. The idea is a horseshoe shaped bracket for your hoist or chainfall, stick the bracket sideways above and below your frame and secure your engine to the bracket with ratchet straps. Then you can just unbolt the engine from the frame and lift it up & out the side without manually supporting all that weight. SOHC CB750 engines are about 175lbs.

Edit: http://forums.sohc4.net/index.php/topic,58210.100.html

Screenshot:
 

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I'd love to rebuild a bike all the way from the frame. Redo the motor and everything. piece by piece. that'd be a neat project.
 
I got a visiting friend to help my manhandle the 640 motor back in. I was able to do it by myself on the 525.

Main bearing failure.
IMG_1098-XL.jpg
Shoulda had a 520 😜

Even on a thumper, I'll build the bottom end and stick it in the bike while it's light. Assemble the top end in the frame.
 
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