Getting engine back in frame

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Mark_smugglers

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Hi

Am progressing with the rebuild of my 1972 750 combat and after tips for getting the whole lump back into the frame.

The barrel and head are on as I didn’t fancy doing that in situ. The bike is complete so I won’t be laying the frame over the engine.

I have read a few threads and watched the odd video but all tips are gratefully received.

I am presuming it goes in from the r.h.s., and the back end gets slotted in first?

Also, am I right in thinking the front mount goes on engine whilst on the bench? Or do I give myself more room if I wait until it is in frame?

all tips much appreciated.

Thanks
Mark
 
Looked up Search and this is what I came up with, sorry I can't post shortcut as I'm on phone;

Advice for fitting engine to frame
March 22 2017
 
That’s how I have done it Mark, from the RHS slotting the rear of the cases into the cradle first. But you must leave the front mount OFF and fit this after the engine is losely secured.

Put lots of protection over the frame paint (you shudda been stockpiling kitchen roll tubes for a few weeks already).

If the frame is well protected you can take your time, resting the engine weight, and inch it into place a bit at a time.

Personally, I find it fairly straightforward, one of those jobs you tend to worry about in advance, but then it’s over with surprisingly easily. If the weight is an issue for you, a trusted pair of second hands will help.

IIRC it is best to fit the gearbox before the engine.
 
Leave the front iso off until the engine is in. But I think you still have to jack up the engine after it is in to wiggle the mount in.
Do not put all the engine mounting bolts in I think it has to rotate up and back a little. I did it a month ago and I already forget! :-(
 
Mark_smugglers said:
so fast Eddie : t be clear, are you saying put from mount on first or leave it off until in frame?
Thx
Click to expand...
Seriously ??

I couldn’t imagine better video evidence to show that the engine should be inserted WITHOUT the front mount!

I think it should also be noted that the procedure is fairly well described in the WSM.

In from the RHS, no front mount fitted. It’s a fairly doable one man op.
 
Any friends that are riggers? Or millwrights? Jobs like this are easier if the participants can visualize/have experience. Be warned though, the gratuitous beer you need to supply could be significant.
 
Mark_smugglers said:
That’s not filling me with confidence!

so fast Eddie : t be clear, are you saying put from mount on first or leave it off until in frame?
Thx
Click to expand...
As Eddie said, the video demonstrates how NOT to do it! :)

I was surprised they actually managed to get the engine in.
 
I always do -
-transmission cradle with swingarm attached
-Horn & battery tray
-transmission
-power unit
(tip the assembly up and install the BOTTOM BOLT!!!)
-front mount
-oil tank
-oil lines
-top mount
-drive chain
-chainguard
-Primary inner case (properly shimmed)
-Primary drive
-carbs
-wiring
-rear wheel assy
-footpegs & pedals
-pipes
 
L.A.B. said:
As Eddie said, the video demonstrates how NOT to do it! :)

I was surprised they actually managed to get the engine in.
Click to expand...

And sadly, as soon as the engine was in, they realised the frame needed re painting !!
 
I never fit the whole engine
I always fit the pistons/barrel/head afterwards
There's no issue with fitting the head etc in situ
I always work alone and I don't mind if I scratch anything
 
baz said:
There's no issue with fitting the head etc in situ
Click to expand...
Some people seem to have a harder time than others.

I simply invert the head on the bench, drop in the pushrods, then take a strip of "not filthy" rag and stuff one end in one of the tunnels, and the other end in the other tunnel, leaving a loop that hangs down in front when you flip the head right-side-up.

Tip the head back as you slide it in from either side, then maneuver it forward as you slowly lower it in place. Once you've got the head down in place, carefully slip out the rag, and all should be right with the world.

BEFORE fastening anything down, rotate the crank and ensure the pushrods are equal to each other, intake with intake, exhaust with exhaust, to insure none of them aren't sat on a follower shoulder instead of their proper seat. Loosen off the rockers, also; it relieves some of the tension so the head is easier to torque down.
 
I just went through this with the 920. I did not know to install from the right. It went in easily from the left though. Solo, just a minute or two. That was with the head on, trans and cradle already in place. Front iso mount off, definitely! It goes on easily afterward.

There is a ceiling mounted electric winch above the bike lift. It comes in very handy. You can lift an inch or two via the big frame tube and get extra room for the engine. I removed the shocks, that way the cradle will pivot on the rear iso mount. Without that it would be good to block things up to get the best possible position of the cradle. Once the top engine bolt is in its easy from there.
I've had a struggle getting the head on insitu in the past, wouldn't recommend it unless there was a need.

Glen
 
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baz said:
I never fit the whole engine
I always fit the pistons/barrel/head afterwards
There's no issue with fitting the head etc in situ
I always work alone and I don't mind if I scratch anything
Click to expand...
The ‘with or without the top end’ question is just personal choice. The engine goes in easily either way. But, of course, it’s much lighter and easier to handle without.

Personall, I prefer to fully assemble the engine on the bench.

Glen, as you’ve discovered, the engine will go in from the left. But due to the design and size of the timing over, it’s just that bit easier from the right.
 
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I have to say I'm surprised that people would assemble an engine and then fit it in the frame
If I bought an engine that I knew to be good I'd fit it complete
If I got a top end problem with my engine I wouldn't take the whole engine out of the frame! I'd just remove the head
I assume from this that people must remove their engines complete to take the head off?
Horses for courses I guess, we all have our own ways
 
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