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xs650 oil and dragging clutch

Discussion in 'The Garage' started by andy2175m4, Feb 10, 2018.

  1. andy2175m4

    andy2175m4 XS650 Member

    my 650 was shifting hard so installed a new shift shaft and changed the oil. took out the old brown oil (sae unknown) and put in regular automotive SAE10-40 oil,
    now the clutch drags even more and the bike shifts harder still
    what is the best oil to use to reduce clutch drag and shifting stiffness ?

  2. MaxPete

    MaxPete My float bowls seem to have stopped leaking!

    Hi Andy and welcome!

    The XS650 normally runs 20W50 viscosity oil - so you are already using a lower viscosity (i.e. less “sticky”) oil. Frankly, I wouldn’t do that for too long and particularly not in a hot climate like Los Angeles. These old gals run hot enough and if you got into stop and go traffic (unlikely as that might be in LA....), you could cook the engine.

    The only other caveat with oil is to NOT use any oil that has an API “Energy Saver” label on the bottle. This label means that, while the oil provides really good lubrication, it contains an additive package that will cause the wet clutch to slip. There is an urban legend that any synthetic oil will damage a bike clutch - but this is wrong:bs:. The issue is not the source of the oil but rather the presence of that special additive package which messes up wet clutches. I won six bottles of synthetic Harley Davidson 20W50 oil in a draw at my vintage bike club and have been using it in my XS650s - no problemo. It says right on the bottle “Compatible with wet clutches”.

    Now, back to your question about hard shifting. You’ve done everything you can (if not too much...) in terms of reducing oil viscosity and I think it sounds as thought you have sorted out the shifter shaft - so IMO, you need to look at the clutch adjustment and then at the clutch cable and actuator “worm” (which lives inside the LH engine side case cover), and then at the clutch itself which lives inside the RH engine case cover - in that order.

    There are lots of discussions on the XS650.com Forum about clutch adjustment and with good reason. The XS650 does have chronic difficulties with shifting and particularly with finding neutral while stationary. Most of these problems are actually related to incorrect clutch adjustment or poor clutch operation due to worn parts or incorrect assembly. Adjusting the clutch requires several key steps:

    - back off the cable slack adjuster on the LH handlebar clutch lever so that the cable is slack;

    - under the little chrome cover on the LH engine case there is a small JIS (looks like Phillips but it isn’t) screw with a locknut. Loosen the locknut and then turn the JIS screw in until the you feel it juuussstt bottom out - then hold the screw still while you and tighten the lock nut. (and don’t go crazy on it).

    - now go back to the LH handlebar lever and adjust the cable slack until the clutch lever will juuuust move a little before it begins to pull on the clutch cable.

    If that all doesn’t work then go to the.....

    CLUTCH ACTUATOR (aka the clutch “worm”)
    The clutch actuator worm needs to be disassembled and lubed to work properly and there is lots of info on the XS650.com Forum to help you do that little job. Just search for “clutch adjustments” or “clutch worm” and you will find it. If you need a new worm, they can be had NOS on the web or a reasonable replacement is available at MikesXS. The LH side case gasket doesn’t seal anything - it is really there to keep water out of the alternator so don’t fuss too much if you mess it up when taking it off.

    While you are in the LH side, check the seal on the clutch pushrod - it is a common source of oil leaks. The seal can be replaced without too much hassle - search on the forum and you find tons of advice and even videos on how to do it.

    Also, be sure to tighten up the big nut on the countershaft sprocket (the one that drives the chain). That nut tends to loosen off and the seal behind it will then leak. The seal itself is almost always OK - and so tightening up that big nut will normally stop the leak. Note the sheet metal anti-rotation washer on the nut - fold the tab down BEFORE tightening and then fold it back up after you torque the nut.

    The other thing to check at this point is the clutch cable - is it in good shape or frayed and does it need lubrication? New clutch cables are cheap and usually better than anything that is 40 years old. Motion Pro branded cables are reputed to be good. Be sure to check your shop manual (without which you should not work on the bike) and route the clutch cable properly under the fuel tank and in the vicinity of the carbs.

    I can confirm that the correct clutch - and throttle cable routing is NOT obvious and it is VERY easy to get it wrong and cause poor clutch - and throttle - operation.

    If working on the clutch actuator worm and the cable doesn’t cure the problem, then you’ll need to get into the...

    If you get into the clutch itself, you WILL need a new engine side cover gasket because it does seal engine oil in and you don’t want it to leak. There about 10-11 6mm socket head cap screws (Allen head bolts) that hold that cover on. You need to keep track of which ones go where (there several different lengths) and which ones have little copper sealing washers on them. Basically, all of the lower 5 or 6 SHCS have a copper washer which helps them to seal engine oil - while the upper 5 or 6 SHCS do not need a copper washer. BTW - most of the folks who have done this job seem to have found that the copper washers are missing from their bikes - and as a result, they often have a slow oil leak on the RH side...but its easy to fix.

    Again - there are lots of XS650.com Forum threads on servicing the clutch - I’d read a few before you start. Here are a couple of other general tips:

    1) Getting into an XS650 clutch is not a particularly big or difficult job - and the easiest way to get access is to simply lean the bike over on its LH side and sit down beside it. I propped mine up using a car jack stand under the LH exhaust pipe which I covered with a rag to prevent scratches on the beautiful chrome (thanks GeorgeOC!!). This tilting operation prevents all the oil from leaking out and makes working down there much more comfortable if you don’t have a bike hoist.

    2) You will need a big metric socket to remove the clutch centre nut (and it may be a 28, 29 or 30mm nut - MamaYama used all three sizes, seemingly at random :)wtf:) - so there is no way to tell which size you’ll need before you see it “in the flesh”). So much for the ultra-methodical Japanese....
    These sockets are available at Harbour Freight and are not very expensive. The best way to get the nut off is with an electric impact wrench (i.e. a rattle gun). I simply put the bike in gear and held the rear brake down - and it came off in a flash. I did the same thing to torque it back on after the repair.

    You’ll also need an impact driver (which is not electric but requires a good-sized hammer) because the stock clutch screws have JIS (sort of like Phillips) heads and they are often buggered-up. An impact driver is definitely the way to go here and you might want to replace the stock screws with some nifty socket head cap screws or “SHCS” - aka Allen screws). If you do switch to SHCS, be sure they are the correct length BEFORE you install them. If they are too long, you will damage your engine case and the clutch will not work properly.

    A screw driver with the correct JIS bit (the best brand is called VESSEL - available on eBay) and a set of these tools is essential for working on Japanese...anything: bikes, cars, cameras etc. Again JIS (Japan Industrial Standard) looks like Phillips but are sufficiently different that a Phillips driver will often strip the head of a JIS screw. As noted, a JIS impact driver (you want the silver handled IMPACTA #3 JIS driver) is ideal for doing a 650 clutch because those six clutch screws are often tight and sometimes have buggered-up heads.

    You do NOT want to have to drill them out.

    3) You will find a whole bunch of special washers, spacers and funny little parts in the clutch assembly - so have a clean towel on which to lay them out and keep careful track of what goes where. Having said that, it may be that someone has already been in there and reassembled the clutch incorrectly and that is why your shifting is difficult - so get a blow-up drawing and check carefully as you disassemble it. There is only one correct way to put it together - but lots of incorrect ways.
    If you find that the little axial thrust bearing is bad - don’t despair, the MikesXS replacement is cheap and is reported to make a BIG improvement in clutch function.

    4) If your electric starter doesn't work very well - the problem is nearly always starter gear #4 which is located inside the RH engine case just behind the clutch.
    Sooo, while you are inside the RH engine case - you should check your electric starter gear #4. Again, this is a very common problem with the XS650 and yet, it is a very cheap and simple repair and so I'd advise you to search the Forum for threads on the starter gear repair. You will find TONS of good info on it.

    I’ll close by wishing you luck and encouraging you to ask lots of questions, get a shop manual (downloadable for free) the proper tools and please post lots of photos.


    Last edited: Feb 10, 2018
    Wulfbyte, JRay77, spectra and 5 others like this.
  3. mrtwowheel

    mrtwowheel Honda Etched On Brain

    I don't think the 10W40 caused this issue, more than likely a clutch adjustment or clutch linkage issue. In my neck of the woods, I'll be using 10W40 in all of my bikes, hasn't caused any problems in many decades.

    MaxPete likes this.
  4. grizld1

    grizld1 Grumpy old man

    Uh, Pete, 20W50 works OK as a summer oil, but if it's the "normal" lube for the XS650, don't you think Yamaha would have mentioned that somewhere in the owner's manuals, service manuals, or service bulletins? 10W40 works just fine in these bikes. So does 15W40 diesel oil (I like to add a little shot of ZDDP booster). So does the recommended 20W40 Yamalube. Using motorcycle specific oil will avoid clutch killing molybdenum additives and/or ZDDP depletion.
    JRay77 and MaxPete like this.
  5. xjwmx

    xjwmx XS650 Guru

    I'm suspicious the new hires get to work on the motorcycle oil, like gggG's worry about the new hires at the machine shop getting the insignificant (to the shop) jobs.
    FWIW I read somewhere that STP oil treatment is in large part zinc booster additive.
    JRay77 likes this.
  6. MaxPete

    MaxPete My float bowls seem to have stopped leaking!

    OK - now you’ve taught me (another) lesson Grizld1 - I have always had it in my little 1 HP brain that the correct oil IS 20W50 for XS.

    HMMMMM. I wonder where I got that notion.
    robinc likes this.
  7. robinc

    robinc Member of the 'yellow meter gang'

    Well Pete, I'll admit to be schooled on this here as well. I have always run 20W50 4 Stroke Oil.

    So, I just went out to my 32° F shop and checked my manuals.

    Haynes - SAE 20W50
    Clymer - SAE30W or 20W40 SE
    Yamaha Service Manual LIT-16004-00 1971-1980
    XS1, XS2, TX650 - 10W30 SD
    XS650B, D, E / 79 XS650SF, 2F / 80XS650G - SG - 20W40 SE
    MaxPete likes this.
  8. 5twins

    5twins XS650 Guru

    I've never seen "energy conserving" 40wt. or above. I suppose those oils are too thick to begin with for those additives to help. I tried 40wt. once in my 650 but didn't like the added top end noise the lighter weight produced. I'm back to 20W-50. I don't use fancy and/or expensive oils, just cheap automotive ones, but I change it often (every 1000 to 1500 miles). My oil of choice lately has been the Walmart brand. It's cheap and comes in 5 quart jugs. The sales person there told me Mobil makes it for them.
    MaxPete and robinc like this.
  9. MaxPete

    MaxPete My float bowls seem to have stopped leaking!

    Hmmmmmm.....5T - I’m pretty sure that I have 10W40 with the API Energy Conserving label in my stock of lubricants. I don’t know if the higher viscosity oils have that anti-wear additive package but I don’t see why they wouldn’t. There are lots of engines that run higher viscosity oil - and they would, I am sure, benefit from the anti-wear packages ability to reduce friction.

    As I said, the problem isn’t the viscosity or even the anti-wear package itself - the problem is the wet clutch and the incompatibility of the clutch disc material with that package.
  10. 5twins

    5twins XS650 Guru

    Find that bottle if you can. Like I said, I've never seen it on 40wt. and thicker oils. These are the API rings we get here in the States, not sure if you get the same .....


    "Energy Conserving" is missing from the ring on the thicker oils.
    TwoManyXS1Bs likes this.
  11. MaxPete

    MaxPete My float bowls seem to have stopped leaking!

    Will do - but it might take a while. The DCW is sort of crowded right now and because it’s so cold out (see our lovely pool in the photo?), I am not spending any time in there!
    As I’m sure you know, “API” is the American Petroleum Institute so I’m pretty sure we get the same stuff as you.
  12. andy2175m4

    andy2175m4 XS650 Member


    I found another article on clutches showing a clutch basket with wear grooves, that would retard the clutch plates from moving freely in and out, this makes a lot of sense, this condition would physically prevent the clutch plates from fully separating when the clutch is pulled in. The other things I tried made no difference. I will remove the clutch again and see about filing down these grooves (if I find them in the clutch). Or install a new clutch basket. BTW the tangs on the clutch plates resting on the basket are steel, and the clutch basket is aluminum so that wear will always be there. My 650 has 26,000 miles on it so wear in the clutch basket, steel on aluminum under load, is gonna happen !
  13. mrtwowheel

    mrtwowheel Honda Etched On Brain

    Show us some pictures when you get it disassembled. Seems that you're moving in the right order. Warped steel clutch plates maybe?

  14. andy2175m4

    andy2175m4 XS650 Member

    The clutch basket in the '75 (my main project) was not grooved or worn so that was not the problem, so needing another fix to try, I took all the clutch plates out of my '79 donor engine and put them in the '75 and lo and behold the clutch dragging problem is completely gone ! Neutral is right where it should be and easy to find !!
    So it was a bad set of clutch plates, they could be warped, or the surface finish is too slick, but in any case the old plates are NFG and newer set of used clutch plates fixed it.
    New clutch plates would probably be even better but who has time to wait for UPS ?
    I did a lot of reading for this one and some posts said that 650's are notorious for hard shifting, but I disagree, by simply replacing the clutch plates shifting now just fine. definitely not a design flaw but rather a worn clutch.
    mrtwowheel and TwoManyXS1Bs like this.
  15. mrtwowheel

    mrtwowheel Honda Etched On Brain

    Bravo, but take this one step further. Do some detective work on the clutch plates you removed, measure thicknesses and check for flatness and burrs on the edges. Myself, I'd feel better knowing what was out-of-whack.

  16. andy2175m4

    andy2175m4 XS650 Member

    Thinking at first It might be the oil, I tried 2 or 3 different oils, made NO difference. tried 2 types of "4 stroke motorcycle oil" no help,

    After I swapped out the clutch plates went back to 10W-40 regular car motor oil, worked fine.

    So I looked carefully at the "old" steel and fiber plates, and did not find any warped plates, and did not see any burrs on the teeth that might hang up on the basket, did not see any wear on the clutch basket or clutch hub, so the only visible difference between the old plates that were "draggy" and the slightly newer plates that work well, was the appearance of the surface finish. the "newer" plates from the salvaged '79 engine looked shiny, and old plates had a matte finish, so I don't really know what's different other than the plates are newer and have about 1/3 the miles of the old plates. Makes a world of difference though, brand new clutch plates would probably be even better.

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