What engines can fit (easily) into an FJ600?

I've had an FJ600 for many years. Last fall, after a few years in storage, I finally got it running good enough to ride it regularly. This summer I did some additional clean up and rode it a couple of hundred miles in a few rides. I decided to sell it (way too many bikes) and did so late last week. Two days later the guys who bought it said it wasn't running anymore and the starter engaged but didn't even turn it over. I told them to bring it back. They dropped it off and I looked at it the next day. Engine was seized. Under 13000 miles on the bike. It ran *great* for me so I wondered what happened. I got the engine unsseized and turning over on its own with the starter. I changed the oil and then noticed it.... #3 broke a rod and blew a 2" hole in the engine case.

Time to scrap it or find an engine that can "easily" replace it. I've heard (from AI... ha!) that xj550, xj600, and fz600 engines will fit right in. Do any of them? or some other engine? Once in, how about the carbs, airbox, and electricals? I'd appreciate any insights otherwise this fun little bike that I was riding with no issues just earlier last week will be turning into parts on eBay.

Sadly, but thanks in advance!

 

I wouldn't have taken it back. What did they do, run it way above red line for miles on end?

 

My thoughts exactly. XJ/FJ engines are so tough that one has to be trying to hurt one like that.
@RHKIII, there is a parts FJ on the local Marketplace for cheap....

 

YX600 Radian is another potential donor

 

I didn't see any parts FJ600 on marketplace. Do you have a link? (Marketplace is horrible for searching for anything.)

I would have preferred not to return the money, but I didn't have a clear story from them that they did something wrong... and they came across as decent kids. I certainly suspect that they destroyed it, but didn't want them to be out money that they likely didn't have much of when I couldn't be absolutely sure. I would have wanted a seller to do the same if the situation was reversed.

I want to get it going again if the price is resonable but I'm not going to make it a money pit that will never return it's value. I have many more bikes that I prefer to ride so this would be a "restore to sell" rather than a "restore to keep".

So far I'm only hearing the Radian engine would fit. I suspect I need it complete? (carbs, airbox, electicals...). Is that right?

Any other engine swaps that would work? The more possibilities the better chance I have of finding one that has something like front end damage and is being sold as parts. For example, there are some XJ550's near me and also a '92 Seca II (all damaged beyond repair so good to strip). There is also an XJ600 motor in Ontario.. but it's year isn't listed. I'm assuming that is also a Seca II (based on how it looks).

I have found a number or Radian's that are "reachable" for me. I'd prefer not to get one that could be restored itself. At least one I found was wrecked and another is without a title, so they are candidates... although longer (but doable) drives.

Until then I'm working on a couple of FZ600's (fighting NY for a title on one) and an FZ700 that I just picked up that I really like to look of!

Thanks again for any information!

 

As you've learned any XJ550 (seca or maxim) will fit or FZ600 or YX600 also.
You will want to keep the FJ carbs as they are 32mm and the FZ/YX are 30mm
The carbs are wider spaced on the FJ (same as XJ650) so you need to keep FJ air box and rubbers.
Keep all the FJ pickup coils, rotor and TCI as you cannot mix and match these components.
Seca 2 stuff will not fit.

 

I was told once the Radian and FZ had the drive sprocket spaced further out to clear the wider rear wheel but never confirmed this. I put an FZ motor into a girlfriend's FJ many years ago but it was sold shortly afterwards, chain misalignment wasn't noticeable

 

xj600, would fit right in, its the same engine, but it depends on year of your FJ.
xj600s changed in about 1987, with the alternator being placed on the end of the L.H. crankshaft, instead of just beneath the carbs, if you dont get the similar year you may need to do some wiring alterations
basically, if your FJ has the (end of crankshaft) alternator , then you will need a post 1987 xj600 with the same alternator position

 

Thanks! I'll go on a more deliberate hunt for 550's and Radians near me. I'll try to keep folks posted for help and advice!