XS400 SOHC engine damage - caution, graphic images!

Bear Hands

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Soooo, having already invested a fair amount of time in the frame of my cafe racer project, I thought I should probably look into the engine, especially as when I bought the bike the engine was knocking more than a very knocky thing. I warn you guys, this thread contains images which some viewers may find upsetting...
 
I started at the top (obviously) and straight away it was obvious this engine is in a bad way.
Camshaft is scored and burnt on the center journal and one lobe (the others are not great) so thats scrap:
Cam.jpg


Cam follower/rocker arm is also scored and generally f**ked:
followers.jpg


Centre "bearing" journal, whatever you want to call it, its toast:
head bearing.jpg


Bodge of the week (drum roll please) goes to the snapped cam chain guide glued together using a junior hacksaw blade! Well done sir.
chain guide.jpg


Nothing much of interest in the piston department, normal wear which is probably too bad to use.
So down to the bottom end...
The main bearings looked ok-ish:
main bearing.jpg


But I could feel the wear on the crank journal, VERY ridgey:
main journal.jpg


So I took the "better" of the two rods off:
good bearing.jpg


And thought "hey, that journal doesnt look too bad, maybe the crank can be saved!"
good journal.jpg


And then I took off the other rod, the one which had about 3mm of up and down play...
bad bearing.jpg

And the crank:
bad journal.jpg


I'm going to guess this engine suffered oil starvation. The bad bearing had spun in the rod and extruded the bearing material out the side, I have no idea how it didnt seize up and shit the rod out the block.

And to top it all off? Yep, cracked kickstart journal:
crack start.jpg


Anybody in the UK selling a 400 engine? Though looking on eBay I can get crankcases, crank, cylinder head etc for around £200.
 

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    crack start.jpg
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No worries guys, let’s look on the bright side, now I’ve got justification to swap out the crank for a 250/360 one, and the rods can go in the bin and get some FJ1200s ready for some bigger pistons .
Bit bummed about the crank cases and the head/cam tho.
 
That's the worst one I have ever saw. WTF with that saw blade??? I would be looking for a complete other motor that runs well. The parts and machine work to that one would be a waste of money.
 
Just to keep this updated, I will not be beaten!
So far I've bought the following:
Crankcases, brand new 250 crank (lighter than the 400!), xj1300 con rods, gpz900 pistons, head with cam and rockers, new cam guide, new cam chain, gasket set, clutch pushrod (the old one was snapped in half!?).

Right now everything is getting scrubbed, then the cases etc are off to be blasted and the barrels are going for a rebore to 72.5mm for the (soon to be modified) GPZ pistons.
 
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