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*Ouch*

Discussion in 'Technical and Troubleshooting Torque' at netrider.net.au started by UDLOSE, Feb 13, 2012.

  1. Yesterday was the first sunny day in weeks, I was riding my VTR1000F on old road with a smile on my face when suddenly I heard a massive rattle so I hit the kill switch and I rolled to a stop on the side of the road. The bike previously had a bit of timing chain rattle I've been meaning to replace the tensioner in it. Straight away I figured the tensioner had totally let go. The other theory was oil starvation from wheelies, it sounded more like a rattle than a knock but it's hard to tell with a helmet on. My mate rescued me in his ute and we pulled the rocker covers off and everything was still lubed and looked ok. One side was fine, the other had a limp cam chain and yep the tensioner was ****ed. The chain has skipped links, which means valves into the piston :(

    We pulled the offending head's cams off and sure enough the exhaust valves were bent. We pulled the head off and the 2 exhaust valves are bent as all shit but the piston looks ok but I've still gotta clean it up and look for cracks. Fingers crossed we can get 2 new valves, new tensioner and re-time it. I'm still on the fence about doing the timing chain since it looks like a huge job and the teeth look good (bare in mind this bike is a cheap shitter). I'm glad I switched it off with 2 secs of hearing the rattle. c094755a-79dd-a5a9.

    c094755a-79f7-80a0.

    My mate is taking the head to his mates shop to get a price on the valve job.


     
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  2. Timing chain is easy, Join the new chain to the old chain and just pull it thru,

    It only gets hard if you lose the chain down the hole, Hahahahahaha
     
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  3. you are a cruel man, deadman :LOL:

    That could have been a whole heap worse, nevertheless, mate...

    Hope it fixes ok.
     
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  4. Thanks guys. Deadman I figured that if I did the chain I'd do the sprockets. The two cam ones are easy but looks like alot of work to access the lower one(s). I gotta get my hands on a service manual first and price the parts before I decide.
     
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  5. Ah yes, Same model bike same problem same symptoms, same result crossing the Bogong High Plains rd. I sympathise, it was a mates bike though and he had to pillion home with me very sad and unhappy.
     
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  6. Ah bugger, yes a quick google shows this is extremely common :(

    Lucky for me yesterday I was riding with my gf and my mate. My mate rode my gf's 250 and I doubled my gf home on my mates bike. I got his chicken strips off and he loves the 250 so he was happy. We regret not finishing our ride first.
     
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  7. Second post dissapeared,

    I have lost The chain down the hole.

    Its even worse if you loose a nut down there, They are impossible to get out,

    Lucky you stopped in time,

    Mate dropped a primary chain and it snapped the crank in half and walked out the front of the motor,

    I am glad I now ride a Honda,
     
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  8. As opposed to a firestorm?
     
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  9. Ooh, a Honda with camchain problems that lunch the motor. Whoda thunk it :D.

    Seriously though, looks like the damage could have been a lot worse so hopefully you'll be back in business for the price of a couple of valves and a camchain and tensioner.

    I don't think I've ever seen anyone replace camchain sprockets. Indeed, on older Jap fours with central Hyvo chains, I'm not sure it's even possible to do the crank sprocket. Camchain sprockets run in a pretty ideal environment (nice clean oil bath) so they don't seem to suffer all that much.
     
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  10. Cam Chain Tensioner sounds like a can of marbles being rattled.

    They dont usually let go, or disintegrate, But if it gets too loose, the cam chain can jump a tooth or two, putting the timing out and as above, bending a valve or three and punching holes in the pistons.

    Also can bend a rod or two, ending up very expensive.

    Especially if you are travelling quickly,

    Your very lucky you shut it down in time,

    Get onto a Viffer specific site, you can down load a manual for free, some one has usually down loaded the lot,

    Blackbirds usually do them at about 35,000 Klms, $40-00 on the internet, $70-00 from Honda here, Two bolts, then just pull out the Tab, Easy Peasy,

    Bloody glad I dont ride a Triumph any more,

    Cheers,
    Brian,
     
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  11. Thanks Brian, I got my hands on a service manual today. It's got all the timing info but I can't find anything about changing the timing sprockets. I think I'll just put the tensioner in and be done with it.I'm not planning to keep the bike for a long time.

    I'm the other way around I miss my triumph lol!
     
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  12. You didnt have an old one, every 10,000 I put a new top end in it, Thats a lot of top ends,
    Either a Rebore, pistons and rings, or new barrels, pistons and rings,

    I even had 12.5 to 1 pistons in it at one time, That thing fluttered the eyebrows. Hahahahaha

    Make sure you really flush the cases out, Any microscopic steel powder or bits in there will blow your bearings, Quick smart,

    Honda Motors are pretty bullet proof these days.

    Spin the motor slowly, look down the hole with mirrors or Thru the side covers if you can,

    Look at the sprockets, If they are still standing up straight and not curved over, teeth missing.Etc,

    Just pit it back together,

    Make sure the Heights of all the pistons are the same height, Push down on the crown as it comes up the bore,

    It should be allright,

    Not a service manual,

    A complete workshop manual, Machining tolerances.Fluids, Etc, Has all the part numbers as well.

    It near tells you how to pick your arr Ummmm Nose, Hahahahaha
     
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  13. The tensioner didn't appear damaged it was just seized up. Luckily it didn't let go under full noise, I was just slowing down from 80 to 60 on a straight.

    I think the clutch was in when it skipped teeth luckily.

    I'll be changing the oil and cleaning everything up though.
     
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  14. Luuuuuuucky,
     
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  15. Very lucky.
    Clean the piston and check for cracks in the ring grooves.
    Cam sprockets, as everyone else has said rarely need replacing.
    Pull inlet valves and check for straight. replace the tensioner.
     
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