Dust on Carb intake boot.

Discussion in 'Thumpers' started by usarider777, Nov 5, 2012.

  1. usarider777

    usarider777 Adventurer

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    Hi to all.
    A friend brought his bike Honda XR650L to me to have a look at it.
    It has less than 15000 miles, but it is using quite a bit of oil.
    After I removed the air cleaner I discovered some dust on the carb intake boot.
    Is that a common problem? Could this cause the engine to use oil?:norton
    [​IMG][​IMG]

    Would like to know what your experiences are.
    Best regards:
    Uli
    #1
  2. TNC

    TNC Candyass Camper

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    I hear some guys claiming their dirt bikes used in real dirt conditions "never" having even the slightest dust residue over time in the clean side of the airbox. Even with very meticulous care for oiling a foam filter with the best foam oils available and using high quality filters...even dual element filters on occasion...I have always seen the tiniest film of dust in the clean side of the air boot over time. It's not consisted of real particles or crud, but if I run my finger in there, I can see that I rubbed off a film of "something" that looks like dust. On the other hand, without an analysis it could mainly be an oil film.

    That said, I see more crud in that pic than I would be comfortable with. Sometimes a severe "dunking" in a water crossing can allow water to push dirt through the filter and around the perimeter which can be a one time deal. In any case I think there's too much visible dirt/crud in the boot there. What kind of filter was on the bike? Determining with exact diagnosis that dirt is what has caused oil burning in this case might be difficult to assess.
    #2
  3. usarider777

    usarider777 Adventurer

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    It has an original Honda Airfilter. Hopefully since it was only serviced by Honda.
    #3
  4. usarider777

    usarider777 Adventurer

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    Another problem this bike has is that the timing chain jumped.
    A few month ago he took it for service. After he drove a few hundred of miles I met him.
    His bike made a terrible tappet noise. I checked It for him one tappet had about a 1/4" of play.
    My guess is that this gives a knock on the timing chain each time this valve opens, and I wonder if this could be the cause of the early timing chain failure.
    Has anyone had a similar experience.
    The owner now thinks Honda is rubbish because he has so much problems.
    I am now trying find out if there is a real reason for the timing chain to fail early.
    Any advice would be appreciated.
    #4
  5. Beezer

    Beezer Long timer

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    dirt past the filter eats piston rings & cylinder walls
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  6. creaky

    creaky Been here awhile

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    The crud in the intake tract is a sure sign of neglected filter maintenance. The crud/dirt/grit passes the filter and eats up the rings, cylinder wall, piston, piston pin, etc. The timing chain has jumped most likely due to the chain and possibly the chain tensioner being worn out. I'll wager that the loose tappet was the RH exhaust, a common mistake resulting from lack knowledge of how the cam mounted decompression device works.
    #6
  7. mcma111

    mcma111 Long timer

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    Unless you set the engine to TDC and removed the rocker cover to check the cam alignment marks to confirm the cam jumped timing I would bet that who ever did the last valve adjustment did so on the exhaust stroke instead of the intake stroke and the auto decom was activated which will result in the right exhaust rocker having a mile of clearance which will give off a terrible racket.

    The dust in the intake can be resolved by tossing the OE filter and installing a UNI filter along with greasing the sealing surface.

    Lot's of oil use? Rings are bad.
    #7
  8. Foot dragger

    Foot dragger singletracker

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    There are a few things that Ive seen happen with filters,running them really dirty can then make dirt try to crawl under the sealing edge of the filter,if its not greased the dirt can creep under it. Big 4 stroke sucks hard for air so it can suck dirt under the clogged filter. A buddy's KLR did this on a long trip.

    My DRZe had dirt coming in from where the boot clamps on to the airbox,always a layer of dust in the boot until I figured that out,clamp was tight,still leaked a little fine dust in. I also tried the water soluable filter oils for a short while,rode a dusty ride that also had water crossings,that oil was like mud when I serviced the filter,dirt went right through it.
    People love those oils cause they clean so easy with soap and water,once or twice was enough for me.

    Using Honda's K-Mart like stock filter is asking for trouble,they can rot quicker then most if left sitting a while.
    #8
  9. Foot dragger

    Foot dragger singletracker

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    XR650L's arent the longest lived Honda engine ever made,prone to over heating on long hot rides,old technology that Honda just wants to keep selling till it cant anymore.
    #9
  10. Bigem

    Bigem Long timer

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    That is not good, will meet with engine tragedy!!:cry:cry:cry
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  11. usarider777

    usarider777 Adventurer

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    Thanks for the reply.
    The sad thing is that the Honda garage did adjust the tappets incorrectly.
    We try to see if they will do a guaranty job.
    At least we know there is a real cause and we can expect it to last longer when the Bike is serviced correctly.
    #11
  12. Sierra Thumper

    Sierra Thumper Been here awhile

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    XRL's don't need a ton of maintainence, one nice thing about them, and will last a long time with reasonable care, but what they do need needs to be done right, like any job. Counting on most shops to keep ANY bike running well is a big mistake........either your buddy needs to learn how to do the basic maintainence himself, or he's always going to have trouble with shops screwing his bikes up.
    #12
  13. usarider777

    usarider777 Adventurer

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    Yes he is actually considering to ask me to repair it.
    If it was not in the Honda garage it probably would still be running!!!!:clap
    I just want to know somehing about the Honda engine.
    On a Yamaha TT600 you need to put Helicouls once you have removed the Cilinder bolts.
    I did not know that and shortly after replacing rings the thread stripped after only a few miles.
    Does the Honda XR650L also need Helicoils after removing cilinder bolts?
    What thread does it have?
    #13
  14. mcma111

    mcma111 Long timer

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    I have built many XR's and XRL's motors and just a couple of weeks ago did I have to have a cylinder bolt hole heli coiled. This was on a 1991 XR600 that had never been apart and the bolt didn't want to come out so it finally broke instead of un-threading.The later XR and XRL motors use a 10mm bolt and if you follow the directions in the OE service manual to oil the bolts on assembly the parts last just fine.
    #14
  15. Foot dragger

    Foot dragger singletracker

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    Ive taken apart some of the old XL's,1972/73. For some reason some bolts never move that hold the cylinder head and cylinder on. Im not sure if the center cases are magnesium but some bolts are solid and thats it,if they can be forced out a pile of white powder is left behind,not much left to even heli coil.
    #15
  16. Foot dragger

    Foot dragger singletracker

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    I hear horror stories about shop mechanics pretty regular,local honda shop says nothing older then 1986 can be worked on there,mostly no parts to be had for them.
    #16
  17. usarider777

    usarider777 Adventurer

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    I am talking about a 2012 Model so the screws should get loose.
    But maybe helicoils would not be a bad Idea, it may be easier to loosen the bolts if the engine needs to be opened a few years later.

    I still try to find the reason for the bike using oil. It seems there was not enough dust going through te air filter for the engine to use oil.
    Maybe overheating, The owner says at one time when he was driving about 60 with a heavy load in hot weather, the engine was loosing power.
    Is this a sure sign of overheating or not?
    #17
  18. dflow

    dflow Been here awhile

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    A 2012 which sounds like it hasn't been ridden much due to all the down time. I would venture to say the rings are not seated yet and you will burn oil until they do. Of course that is true within reason and since I did not see how much oil is consumed it is only a guess. Good luck.
    BTW, my bikes have yet to be in the dealer's service bay.
    #18
  19. usarider777

    usarider777 Adventurer

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    I also start to think in this direction Maybe it was not run in properly.
    The first trip wars about 1000miles at a speed of about 63mph it is a straight road almost no braking and acceleration just cruising along for hours in top gear, probably this is not a good way of running an engine in.
    Or it could be that one of the rings had a factory fault and broke.

    The bike has already about 13'000miles, if it is the rings that are not seated yet I wonder if it will ever happen.
    Unfortunately the bike had to be serviced by the dealer or else he would loose the warranty.
    #19
  20. dflow

    dflow Been here awhile

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    A compression test will tell you a great deal about where the oil is going. I don't know that bike well but it could be valve seals/guides as well. Do dry and wet to narrow down the issue. A pressure leak-down test is another means of checking it out.
    #20