Paging the XS650 experts

Discussion in 'UK Motorcycles' started by TOG, Oct 20, 2005.

  1. TOG

    TOG Guest

    There's an oil leak on mine, from the oil seal in the points housing on
    the head.

    Mine doesn't actually have any points, because it's an electronic
    ignition model, so the housing is just empty.

    Oddly, it doesn't leak all the time. I saw some oil by the left-hand
    plug, whipped off the cover, thought: "Oooohh, that doesn't look
    good...", and started it up. Sure enough, oil oozed past the end of the
    cam. Ho hum.

    I cleaned it up, and re-started the engine. No oil leaked at all in
    five minutes' running, and none has leaked since.

    I wondered if some oil had pooled by the seal, and then with the bike
    on the sidestand, worked its way through. But it's been on the
    sidestand for two days now, and it's still clean and dry. I know
    sometimes oil seals weep if a bike's been standing and they've dried
    out a bit, and they often swell as the oil gets to them and stop
    leaking. Fork seals do it from time to time, in my experience.

    Anyway, the XS650 has a ball and roller crank, so has a low-pressure
    oil system, so it's not as if there's a helluva lot of HP oil squirting
    around the top end.

    The cam is supported in four ball races (*waves* at Guy Fawkes) and,
    IIRC, the end housings (points left side, auto-advance right) don't
    support it at all. I'm 99% certain that you can remove the housing with
    the engine just sitting in the frame - three screws walloped with an
    impact driver, and off it comes. Then whip out the seal, whip in a new
    one, and replace the housing.

    Can anyone confirm?
    TOG, Oct 20, 2005
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  2. TOG

    JB Guest

    This is probably what it was. The old seal may have been a little hardened
    over time and the heat of the engine and some oil flow has softened it up
    enough to seal again.
    Don't be deceived by the low pressure. It's pretty high flow rate though. If
    you ever don't torque the cam oil feed banjo bolts up properly, the oil
    *pisses* out in *qty*.
    Correct. but alos replace the 'O' ring and gasket on the housing back face
    too. (some had just O-rings, others a gasket too).

    Also a good point to note on oil leaks, is being *bloody* careful if you
    ever see a from the bottom of the oil feed tube at the front of the engine.
    There is an adaptor/oil-pipe seating piece threaded into the soft ali of the
    top crankcase. It is ****very*** easy to strip the thread out of crankcase
    the you try to 'nip up' the oil tube bottom nut too tight without holding
    the adaptor with another spanner.

    With these engines oil quality is everything. The cam may run in 4 ball
    races, but the rockers and cam lobes suffer very badly if crap oil is used.
    On this note also, is to make sure both oil strainers/filters are clinically
    clean. The one in the clutch casing is easy enough, but the magnetic one on
    the inside of the front sump plate is prone to getting blocked and the brass
    mesh getting ripped. These are often overlooked as most people seem to only
    undo the two 27mm oil drain bolts when changing the oil (1)

    (1) you may one day get a nice surprise on removing the rear magnetic drain
    bolt. If you reomve it and see a sort of cylindrical piece of hard steel
    attached to it, congratulations, you have discovered the only weak point in
    an XS650. The engagement dogs from the 2nd/3rd gears!).

    If you do keep it, we'll have to have a natter over a beer next time I'm in
    Sutton. I *love* these engines.

    JB, Oct 20, 2005
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  3. Noted. Good Mind you, the oil is coming out of the seal - visibly - not
    the housing/head joint. It's now pissing out.... But yes, I'd better get
    a gasket and/or O-ring too. The seal is now ordered.
    Heh. I did just that with my first XS650, in 1981, having just completed
    a top end rebore and rebuild. I was bolting on the oil feed pipe as
    about the last task, and stripped the thread.

    The air turned blue. In the end, remembering it was a low-pressure
    engine, I cleaned up everything, did up the adaptor as tight as it would
    go without then spinning round (ie: not very), sealed the joint with
    Araldite, and re-mounted the oil feed pipe.

    It was still like that a year later when I sold the bike. Didn't leak a
    drop. I pointed it out to the buyer, and he wasn't fussed.

    For the rest - yes, I'm aware of all the oil filter and gear issues.
    I've had these bikes before, remember ;-))

    Anyway, just been for a ten-mile pootle on it (yes I am keeping it, for
    the moment anyway), and apart from the oil leak, it's gorgeous. Engine
    seems mechanically slightly noisy - not rattles, or rumbles, or camchain
    clatter, just... well, noisy, but then it's on the stock cans. In the
    past, I've always used naughty pipes and never been able to hear the
    engine at all.

    Beer? Sounds good to me. Email me.
    The Older Gentleman, Oct 20, 2005
  4. TOG

    JB Guest

    I eventually changed the top case to accept the monster liners for the
    1153cc conversion.
    Doh! I had indeed forgotten.
    Me also. (Replace your last four words with "very much since"
    Cheers, will do.

    JB, Oct 20, 2005
  5. Holy Jumping Jehosophat :-O What the ****** were you doing with that?
    Was this a competition engine? Please tell me you used it on the street

    I'm assuming you stroked it as well, because I *think* that about 900cc
    is as far as you can go on the existing block and extra cubes have to be
    obtained by modifying the crank.

    Anyway, I've ordered the seal, gasket and O-ring (I had a rummage
    through my old gaskets and I have some odd XS650 ones knocking around,
    like clucth cover and a variety of O-rings, but (of course) none for the
    housing. Cost of all components is under a tenner, and riffling through
    the Haynes BOL confirms what we both thought - it's just undo three
    screws, pull off the housing, replace seal, replace housing.

    Of course, if it all goes tits-up, then I have a spare engine, too.....
    I'm wondering what to do with the spare bike. It runs *beautifully* and
    the lump has only done 15,000 miles, but the whole bike is shabby.

    So I may break it.

    What it *has* got is decent spoked wheels, and (correct me if I'm wrong)
    I think XS650 spoked wheels are really in the want because the
    customisers can lace whatever rim they want to the hubs (within reason),
    whereas with alloys WYSIWYG.
    The Older Gentleman, Oct 20, 2005
  6. TOG

    JB Guest

    It was used in my old TX750-lookalike 'street legal' flat-tracker. :>)
    Halco modified crank/short conrods with large Mahle pistons and custom
    liners (hence the need for a much modified top crankcase)
    Nooooooo. Build it into a Rickman Metisse chassis. Piss of the
    Morgo/Devimead-Bonnie mob a treat!.
    All of the 650 chop builders want the spoked hubs. They are much sought
    after. I had a pair of Borani (sp?) rims put onto a pair of XS2 hubs for the
    flat tracker.

    Nice easy beasts to work on the old XS650s. Possibly the ideal SOB?

    JB, Oct 20, 2005
  7. Got a pic anywhere?

    Will an XS650 engine fit in a Metisse frame? Those frames are bloody
    rare anyway. I *have* seen an XS650 in a Featherbed frame, tilted
    forward because the lump is so tall.
    Brilliant. They might fetch decent money, then :))
    The only bugger is having to take the engine out of the frame to lift
    the head, otherwise I'd agree.

    The engines are, quite simply, magnificent.
    The Older Gentleman, Oct 20, 2005
  8. TOG

    JB Guest

    Not in it's final form. I may have a few photos from a rally back in 1984/5
    when I took it out for it's first few runs 'in the white' prior to
    plating/painting/finishing etc.
    I got really short of cash just after I'd finished it so it had to go. Took
    my Spada in p/ex + ££££ to a bloke who then went and wrecked it soon after
    or so I heard.
    It was just a guess. It would look nice though. It would certainyl fit in
    the later Rickman Predator chassis. I built two of them. One Z1000, one
    GS1000 based. Tons of room for a tall twin.
    Agreed. In Spades. Mechanically _and_ aesthetically which is pretty rare
    indeed. My old Jota looked amazing from the RHS, but with the alternator
    hanging out on the left, it looked like real bodge job.

    JB, Oct 20, 2005
  9. Hmmmm... rather a large chassis, to be honest.

    I'd like to see it in something like a Tony Foale frame - one of those
    frames with the very large diameter main top tube.

    Somewhere I've got a photocopy of an article in the US rag,
    Motorcyclist, where they took an XS650 as a project bike. They wouldn up
    with something that out-dragged and out-handled a DOHC Honda CB750F.
    Looked good, too. I kept it for all the chassis tweaks and know-how.

    That reminds me - I'd forgotten how shite the ground clearance is. Until
    The Older Gentleman, Oct 20, 2005
  10. TOG

    JB Guest

    The man *is* a suspension God.
    Centre stand >>>>>>bin. New Konis. TR1/XV750 (I forget which) fork springs.
    Job done.

    JB, Oct 20, 2005
  11. Hm. I think we're going to have to Take This To Beer (rather than email)
    so drop us a line.
    The Older Gentleman, Oct 20, 2005
  12. TOG

    Timo Geusch Guest

    The Older Gentleman scribbled on the back of a napkin:

    How shabby? More importantly, how MOT'd?

    CIHAGM before you start?
    Timo Geusch, Oct 20, 2005
  13. Well, all original paint, but faed. Exhausts are whole, but the
    downpipes are rusty. Faded frame paint. Rusty fasteners. Perished tyres.
    That sort of thing. But the engine is superb, it's all there, all
    original, and unmessed-with. No tax, no MoT.
    The Older Gentleman, Oct 20, 2005
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