Head Bolts

Discussion in 'Whizzer Motorized Bicycles' started by RusticoRay, May 3, 2009.

  1. RusticoRay

    RusticoRay Member


  2. bill green

    bill green Member

    Hi what year is you NE5...Bill
     
  3. Quenton Guenther

    Quenton Guenther Motored Bikes Sponsor

    Hi Ray,

    Several have tried the Loctite and report good success.

    Have fun,
     
  4. RusticoRay

    RusticoRay Member

    Leeonardo is a 2008. I pulled the motor out in preparation of Loctite application, anything here I should be worried about. The exhaust pipe is pitted feels like the crust on the intake valve and seat.
     

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  5. Quenton Guenther

    Quenton Guenther Motored Bikes Sponsor

    Hi Ray,

    What grade of gas are you using?
    You might want to check the head for level. You can resurface the head on a flat surface with #220 sandpaper.

    Keep me posted, and let me know how the Loctite works out.

    The late 2007 and 2008 cylinders were problematic due to metal curing issues, but normally the metal works OK after they are reheated.

    Have fun,
     
  6. RusticoRay

    RusticoRay Member

    Im using the good low grade 86 or 87 depending on the service station. The whizzer was running well just at startup when cold it would leak a little fuel out of the head on the intake side. Id let it warm up and rode on. Lately it started leaking air on the exhaust side. Thats where the exhaust pipe was getting pitted I think. Picture was April 28th.
     

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  7. Hal the Elder

    Hal the Elder Member

    HEY RAY:

    It sure sounds like your head is not a perfect plane surface, with both intake and exhaust leaks!

    Send it to Quenton for head resurfacing/milling and combustion chamber scooping, and get a copper head gasket in the package deal!

    That's what I did and I'm sure happy with the results!

    HAL, 2005 NE5, "OSCAR"
     

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  8. RusticoRay

    RusticoRay Member

    Hello Hal, Quenton saved this whizzer "Lee"anardo from a four pound hammer or worst. Bike was dead at 350miles. The head bolts keep backing off and then produce leaks. Im going to use 220grit and a piece of granite stone that looks like a piece of glass and flattin it out and reuse the copper gasket and Loctite.Hopefully I'll be putting more mileage on the bike.
     
  9. Quenton Guenther

    Quenton Guenther Motored Bikes Sponsor

    Hi Ray,

    Because of Whizzers use of 2 different size headbolts, it is very easy to "warp" the head, and the brittle threads on the late 2007 and 2008 motors adds more to the problem. Although re-curing the cylinder metal has helped, it may necessary to do it again[325 degrees for 2 hours in oven and let cool normally]. I would make sure the head is level, and try the Loctite. Of course you can send the head to me if it needs to be re-leveled [no charge, you just need to pay shipping cost both ways].

    Let me know how I can help.

    Have fun,
     
  10. RusticoRay

    RusticoRay Member

    Hi Quenton, Does this mean I'd have to breakdown to the cylinder to recure it or is their another way? I think I can relevel the head with the sandpaper and a chunk of granite.
     
  11. Quenton Guenther

    Quenton Guenther Motored Bikes Sponsor

    Hi Ray,

    I would level the head and use the Loctite. If you continue to have problems, then it may be necessary to try re-curing the cylinder, sadly the cylinder will need to be removed to do so.

    Have fun,
     
  12. RusticoRay

    RusticoRay Member

    Hello, It's 32.30 for a 30gram syringe of 2422 Loctite and 5 days to get it. Willing to share the remainder if someone needs it, I'll even clean the syringe. Thanks for help and suggestions Ray
     
  13. StillDream'n

    StillDream'n Guest

    Hi RusticoRay,
    I just Pm'd you about the rest of the 2422 Locktite :) I need some
    Joe
     
  14. WZ507

    WZ507 Member

    Loose Head bolts

    Rustico,

    I think there is a good chance that Quenton has correctly diagnosed your problem as a soft cylinder, and although your problem manifests itself as a loosening head bolt, the real issue is the head bolt pulling the Al threads out of the cylinder a few thousands at a time. As the cylinder heats up the stress on the threads increases with increasing temperature, and the threads pull in incremental amounts. I think you're slowly loosing the thread in the cylinder. I hope the Loctite solves your problem, but I suspect it's a temporary band-aid for the aforementioned issue.

    If the cylinder were off the bike you could have it tested for hardness to determine if it is in fact soft. If it's soft it would have to be heat treated to restore the hardness. This typically consist of heating the metal to high temperature 700+F to dissolve all alloying elements and provide a homogenous alloy, which is quenched in this state. The quenched part is then heated at a low temperature (250-350F) to precipitate the alloying elements, thus enhancing the strength of the part and providing the final hardness. Heating as Quenton describes will only be effective if the cylinder has been previously quenched in a homogenous state. Good luck and let us know how you make out.
     
    Last edited by a moderator: Dec 15, 2015
  15. RusticoRay

    RusticoRay Member

    Hey WZ507, That is a truely depressing situation. I know your only the messenger. I'm seriously thinking of putting a Honda motor kit from EZMotorbike and drive with some maintanance free miles. Well except for the bike parts.
     
  16. bill green

    bill green Member

    :idea::idea:Hi Guys And Gals What I did on my salt flat bike and others to get rid of soft threads is #1 bake cylinder as Quention stated . #2 Drill just inside the threads all the way threw , Then tap for more thread . #3 Install short allen plugs on holes closest to intake and exaust ports so bottom of hole is pluged , #4 use 12.8 grade allens . #5 Make sure all surfaces have been laped to (0) with 220 wet/dry on granite stone . #6 Use only flat washer on all head bolt And no lock washers .This has worked great for me .Hope it helps ......Bill Ps I had the metal tested and Quenton is correct
     
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