Clutch slipping after transmission oil change ?



  • Hey, just looking for some advice from you experts out there! Today I decided to do a gear oil change on my bike as its been a few months now, so went to the local motorbike shop but they didn't have the normal 10w30 stuff that I use and the mechanic recommended I just use 10w40 and said I should have been using that oil grade anyway so I stupidly took his advice and bought a bottle! Done the normal procedure before changing the gear oil and after about an hour when i was convinced all the old oil was out I put 750ml of this 10w40 in and thought all was good untill I went to go a run and after about 5 mins the clutch started slipping and the bike felt funny as in a bit sluggish going through the gears almost like the gears where stiff especially when down shifting definitely didn't feel right 😭 ! anyway decided to push bike back home and I'm draining the new oil out as we speak but what I'm wondering is it possible it's this transmission oil that's caused the clutch issue? The bike was running perfect before changing the oil so I'm hoping when I put the oil I was using before back in it'll be all good lol...



  • Aww mate don't push the bike home because the clutch is slipping!

    I had this problem with castrol magnetec 10 40. I would be lying if I told you I knew why.

    But 5 30 sorted it out. Well anything that wasn't magnetec lol. I know it's because of the heat range. Remember that the gearbox shares the same oil as the clutch. So suppose that would have something yo do with it.

    Those dt clutches will take a battering. And when they go it is 50 quid and a five minute job! So don't be afraid you might damage something.



  • Thanks @Calum I just imagined the worst like I always do so thought pushing it home was the safest idea lol got quite a few funny stares from people in the process though and got a good workout in to haha .. Well I've got some 10w30 oil coming from eBay as I actually can't get it anywhere local 😞 hopefully it'll sort it out again and if not I'll be on here for help! Clutch and gears where definitely fine till I changed this oil it's so annoying wish I just left it alone



  • @Biker_123 yeah sounds like oil mate. 5 30 would work. To ne fair 10 40 should work. But perhaps a different brand.

    I rode round for ages with the clutch slipping with magnetec oil. Okay I shouldn't advocate it. But if you need transport then it won't kill it if you take it slow. As said a clutch replacement is pennies anyway.



  • Well it's good to know it'll be penny's to fix if the new oil doesn't resolve the issue 🙂 ! Never installed new clutch plates before on a bike so if it is worst case it'll be a good learning experience,I'll just need one of those Haynes manuals and i have a decent set of tools so I'm hoping I'll be able to do it on my own as the local bike shop charge a fortune lol



  • @Biker_123 I have already written up how to replace the clutch on this forumate. So no need.for a haynes.

    Will want a clutch holding tool though.



  • Awesome I'll have a look through the tutorial section for the guide and have a look on eBay for the tool too. I've just picked up a non running 1995 dtr125 with lots and lots of spare parts this evening 2 boxes full of parts to be precise so if my bikes in need of the clutch plates I got brand new ones in the box with the bike hopefully they'll fit 🙂 . Looking forward to trying to fix this non runner as a project I although I think it's seized the kick start won't go down its like its jammed probably a topic for another day but looking forward to trying to fix it myself even if I'm jumping in at the deep end .



  • @Biker_123 Yeah sure throw up a thread. Therr isn't much that can go wrong with these bikes, certainly not a loy that cannot be fixed, so be sure to ask!



  • Thanks @Calum