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Valves adjustment symptoms

Discussion in 'New Riders and Riding Tips' started by kyp, Nov 1, 2011.

  1. Are there any symptoms before you stared to be worried about your valves adjustment, if any? Or do you just follow the maintenance schedule?

  2. Follow the maintenance schedule.

    A loose valve clearance has a distinct tick to it. Unfortunately, clearances tend to tighten rather than loosen and a tight one will generally not show up until you've burnt the edge off the valve.

    On the upside, the valve clearances on modern engines don't tend to move much. It's almost 20 years since I had to actually adjust anything, although I'll admit to probably being lucky (and that doesn't count MrsB's Ural which is not a modern engine, however many Keihin carbs and Ducati ignition systems the Russians might have glued to it). Still check 'em at the recommended interval or somewhere close to it though.
  3. Hard to believe the Ural isn't at the cutting edge of technology :LOL:

    kyp, the maintenance schedules should be conservative and following them you should be right. However if you have reason to doubt, check.
  4. Yeah, what Pat & BM said. When they get loose you can hear it. Unfortunately when they get tight, you can't - and that's the one that hurts.
  5. if your valves are starting to get tight the bike will become harder to start as well.
  6. Thanks everyone for responses. I think I become a bit paranoid in re to my bike but I just want to have clear picture of its technical state.
    What kind of noise is that? When it appears? Does it depend on revs/speed/gear? Sorry for a row of stupid questions :)
  7. What's it sound like? Er ... a light rattle. A tick - tick - tick at idle that increases with engine speed, to tictictictictic. It doesn't change timbre or character when you get on or off the throttle. A tic tic that gets heavier with throttle and goes away when you back off is most likely a leak in one of the exhaust headers, or the head - header junction.

    A slightly loose cam chain can also make a slight ticky noise at idle. When they get bad, it sound like the chain rushing through the winch thing in a roller door. If it's just a faint rustle, be alert but not alarmed.

    A heavier rattle at idle - which only happens when the bike is in neutral and the clutch is out - is clutch rattle and nothing to be concerned about. If you pull the clutch and put the bike in gear and the rattle doesn't stop - be concerned.
  8. Thanks a lot for that. Now it gets more or less clear. I bought my bike a month ago but didn't really put it across until this Monday when I started commuting to work and I noticed a light rattle at about cruising speed(60kph/5k RPM) (this is in addition the the kinda normal 5k RPM vibration of GS5) but not when idling or lower RPMs. I would have thought it might be something wrong with valves adjustment but according to your description it is not.
  9. ... e-e-e-e-r-r-r-r ... Probably not. I'd have to hear it. More likely it's some trivial thing that vibrates in sympathy with the engine and everything else at 5k - like a mirror stalk or the rego sticker holder against the chain-guard or something. ... The stupid little rear reflecter that's been thrown on as an afterthought to keep the Australian Cardigans Department in work.


    I think ...

    A useful hint, for diagnosing funny noises. Go through a list of parts in your mind, visualise them, their size and weight, and imagine what they would sound like if they vibrated, or hit against the part next to them. A Valve looks like a big roofing nail. What would it sound like if you tapped lightly on the top of it with a small hammer? If the camshaft is rotating at half engine speed, and the lobe is knocking the top of the valve because there's too much play, it will sound like you're tapping the top of the valve with a ball-point pen, about ( ... 1000/60/2= ...) 9 times a second.

    What does big-end knock sound like? Imagine a con rod, on the crank, and there's play between them, (the big end bolts have been loosened off enough to allow 5mm of back & forward slop) and the rod slaps from one side to the other, and it's all echoed and magnified by the engine cases, in the way that a guitar or violin amplifies the sound of the string. 'Clonk-Clonk-clonk'

    The general principle holds for most things. Visualise the parts - imagine what they sound like. Now try and fit that with what you're hearing. Is it a good fit?
  10. Just nothing is coming up into my mind. The rattle has really high frequency but as I said it is light(not loud) and coming just under the tank only at speed. I inspected all the external things and bolts seem tightened and nothing seems to be really flappy
  11. hmmm.... One of the clamp gizmos that hold the throttle cable? Or part of the choke mechanism? Does the bike have a mechanical tacho and cable? If the tacho drive cable starts to come loose at the engine end, that can buzz. Gear lever ... rear brake lever ... the engine end of the clutch cable? The side-stand? Does it have a centre stand? What about the plastic side covers? They should sit with a peg through a hole in 3 spots, but if one of the rubber grommets goes on holiday they can make some funny noises.

    I dunno ...