The XJR cylinder head manifold bolts and collector box often get neglected, same thing as the FJ. Replace the manifold bolts with stainless. The collector needs to be looked after or the inevitable happens. But overall the XJR is one of the best old school bikes out there, i'd persevere with it. Loads of smooth power, unbreakable if looked after, clock up the mileage like nothing else, early models still on carbs, low enough to swing you legs over without effort, one of the best in my opinion. Here's my 1200 with a few mods. Built it from parts off Ebay and my old FJ, not much FJ left on it now though.
Don't disagree with any of that Catz - and thanks for your wisdom - as they're pretty bullet-proof retro machines that do some things quite well. The weight is too high up though and there is a lot of it, and there's the need for a 6th gear or slightly higher ratios from 3rd to 5th. The finish on all aluminium parts is execrable however, all Yams seem to suffer much the same. And not recoverable by spit and polish alone.
I've found mine sensitive to tyre combinations and pressures and have settled on Pirelli Angels recently. Tendency to 'fall-in' at manoeuvring speeds due to weight, and to understeer on fast bends on some tyres. But overall, it's been OK as a modern-ish heavyweight, and mechanically very reliable. A hydraulic seal here and there, but otherwise just the usual stuff - oils, filters, chain set (endless and 'off with the swing-arm' in my case as it's actually an easy job with taper rollers), brake pads etc.
BUT, to the main thrust here, how often is yer average guy going to remove the exhaust system and /or bank of carbs just to keep the fasteners running free or take off the collector box to keep the clamps clean and try to keep rust starting from within at bay? Neither job is easy and every time one goes on an expedition to investigate one thing, others emerge! Sleeping Dogs and all that.
The mild steel collector boxes have a life of ten years I reckon, I replaced the first one in 2010 or 11 (see pic), the second one just a few weeks back but with stainless after-market - cheaper in fact than the factory part, and might not corrode as badly. Both the mild steel ones look identically dead after similar mileages - about 35K km in each case.
I wouldn't mind so much if STUDS wouldn't come out - don't want them to do we? But what I just hate is steel set-screws and bolts and allen screws into ali in places where neglect is almost a given. My problem has been 'snapped or rounded-head bolts despite best efforts' leaving stubs that are buggas to get out, and a couple I haven't managed. No room without major dismantle. First time round I used studs and made brass deep nuts for the fasteners I could get at and out (like on a car manifold basically). The original bits (replaced, it should be said) that came out OK 1st time round didn't survive the 2nd round despite loads of copper grease etc, but I have managed with a lot of messing about as mentioned above to deal with the offending remnants with some very awkward one-offery, and the exhaust side is holding up for now ( a couple of hundred miles only so far though).
I haven't had a chance to look into the inlet side rubbers yet . . . it's not yet doing any funnies when running (I know what to expect though, from friends' FJs etc etc), and she ticks over correctly. Just a question of time though.
So . . . I will persevere a bit more as you suggest, I might enlist a spare pair of hands if the motor has to come out (when the frame could have a bit of a touch-up in rusty areas where the paint hasn't done too well either despite being under half the age of a lot of unrestored Brit iron). But shifting it through the trade after a decent-ish clean is probably a better option, unless a mate specifically wants a bargain price lowish mileage one with some work to do, and has the savvy to do it. It needs someone to love it a bit more than I have, to be honest, and there are people who really do like these things, I'm told by people younger than me.
Some of the adventure-styled beasts might be a good option KiwiGF, thanks for that.
And making one would be wonderful RD - just need your ultra-skill levels instead my much more basic ones!!