Viewing 2 reply threads
  • Author
    Posts
    • #3844
      Madcoop
      Member
      • Topics: 4
      • Replies: 7
      Joined:
      Apr 22, 2019
      @madcoop
      Scotland
      GT125R (carby)
      Points: 273

      I’m currently taking advantage of this lousy weather and have the hyo in bits, taking care of a few things before the good weather comes in.

      The plan was just to strip the front end to replace the fork oil and do the headlight upgrade, but now I’m there  it’s got me thinking about the next step which will be valve clearances, chain tensioners, carb clean/rejet and finally the clutch because the old girl has occasionally been misbehaving at higher revs.

      It’s not happened very often, but what I am experiencing is the drive disengaging momentarily, then re-engaging almost immediately. Almost as if it is jumping out of gear and then dropping straight back in again. Kind of like a flick on the clutch lever, but your hand was never near it!

      Predominantly it has only been an issue higher up the revs, under acceleration and in 5th gear, however the last two rides I have taken it has happened in a lower gear (I think 3rd, maybe 4th). As I say it has only happened just over a handful of times.

      Because of the fairly low mileage on this bike and it’s obvious lack of maintenance before I got it, I thought that it would be most likely the plates wearing out, so change them and it would most likely be problem solved. First time I will have done a clutch on a bike, but it will be a good learning process.

      I have also read that the selection forks can bend and perhaps cause problems similar to this, so would like to draw on someone’s experience in this area. I would like to be prepared for what I may find, and I do have another box I could rip apart first if need be. Again though, I’ve never been near a bikes gearbox, and know this will be a huge challenge without the correct tools. Still do-able tho…

      I’d like to keep time off the road to a minimum while still getting these things dealt with, so anybody’s experience of similar problems could really help me plan, so I don’t have a bike sitting in my kitchen waiting for parts longer than it needs to be.

      At least she’s tucked up safe and warm tho…. 🙂

    • #3853
      ♠️ MARCEL
      Administrator
      • Topics: 38
      • Replies: 366
      Joined:
      Apr 22, 2019
      @mf448kxn6
      North UK
      GTR
      Points: 4,203

      Hey,

      I would start by sorting the entirety of the clutch basket.  Which is what youre most likely dealing with; as some of the issues regarding gearing you mentioned are too common when the entire clurch starts to wane.

      When the clutch cover is off  ; also look under the clutch basket where the FOOT LEVER SHAFT joins the cogs there. The teeth should be good and is also the clutch basket stiff (bearings good), basket sprockets good.   Visual inspection basically while the clutch is overhauled.

       

      The gearbox is the last last last thing   anyone wants to deal with.  If you can shift to  5th.  Assume your prawl forks are still intact.

       

      I would deal with the clutch first before gearbox (hopefully not as its a whole other discussion and more time on your hands 😬)

      // Meditation doesn't mean you have to sit still....

    • #3882
      Madcoop
      Member
      • Topics: 4
      • Replies: 7
      Joined:
      Apr 22, 2019
      @madcoop
      Scotland
      GT125R (carby)
      Points: 273

      Thanks Marcel.  😉

      I have the bike built back up now and managed to get her out in between showers. I’ll grab a clutch kit off you at some point over the next couple of weeks and proceed as you suggest. I’m not hugely worried about the prawl forks, just something I had read! The problem has only shown itself a handful of times, and selecting gears has never been a problem once I had adjusted the clutch at the engine swap. Initially 5th wasn’t there, if you remember my post last summer, but it didn’t take me long to find it again once I fiddled with the clutch. Based on that experience I would be even more inclined to think worn plates.

      We need to talk gearing, but when I do the sprockets I’m going to go with the 520. I threw a new 428gg on it which has been fine, but I  still think it could benefit from the 520.

      First things first though. I want to see how it’s goes with the new clutch. Once that is in we can  hopefully put our heads together and make an informed decision about the sprockets. I should have the clearances checked by then too. They were fine last summer, but I’ve put 1.5k on it since and don’t know the history of this engine. Never missed a beat yet tho, so worth looking after!

Viewing 2 reply threads
  • You must be logged in to reply to this topic.
Skip to toolbar