Engine Sprocket Swap

Discussion in 'Motorized Bicycle General Discussion' started by psprat496, Apr 17, 2010.

  1. psprat496

    psprat496 New Member

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    I've got a 66cc Angle Fire with slant head mounted up and everything to my bike but there's one thing holding me back....the chain. It originally came with a #410 chain which is the small one but I swapped it to the larger #415 do to some issues with the idler wheel and what not. I thought the chain would work fine because it looked like it had enough space and pumped on no problem. But when I went to test it, the chain would keep wanting to derail.

    Now here's my question. I have a Skyfire 66cc that uses the larger chain and is now out of use and I was wondering if I would be able to swap the engine sprocket from the Skyfire to the Angle Fire so I would be able to use the thicker chain. If so, how would I do this? I know the kit comes with these small tools for this purpose but I have no clue on how to use it.

    Does anyone know how to go about doing this? Or if it would even work. Worse comes to worse I'll just swap engines but I don't want to do that yet.

    Thanks in advance.
     
  2. RedB66

    RedB66 New Member

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    You should be able to run the 415 on the sprocket. Where is it wanting to derail?

    If you do swap the sprocket out..... The woodruff key is going to determine if you can swap them. If the slot in the sprockets are the same then you're in luck. If there is any play I woudn't advise the swap.

    You should have a puller tool that came with your kit. Remove the cover, pin and ball. Remove the nut holding the gear on (I usually use a couple links of chain wedged in the housing to hold the gear from turning). Then thread the puller on. Make sure that it is seated all the way down because the threads will strip very easily (Trust me!!).

    The puller tool is a two part tool. The larger part threads onto the gear and the bolt looking part threads into the center. A cresent wrench works for holding the larger part while a socket turns the bolt.

    As you turn the bolt the sprocket should come off. There is a woodruff key to watch for.

    Hope this is clear.... I'm sure someone will add any points that I left out.
     
    #2 RedB66, Apr 17, 2010
    Last edited: Apr 17, 2010
  3. psprat496

    psprat496 New Member

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    When the chain is leaving the sprocket. I rolled the bike forward and noticed it would keep wanting to come off the bottom of the sprocket. So what your saying is just remove the pin and ball bearing and then thread the tool on and it should just pop off?
     
  4. psprat496

    psprat496 New Member

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  5. Creative Engineering

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    Good grief!!!

    psprat...please explain "in detail" your problem.

    Here to help!

    Jim
     
  6. psprat496

    psprat496 New Member

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    Ok we'll as you probably know the kit was meant for a #410 chain. I guess the engine sprocket is too small because whenever I roll the bike forward the chain goes onto the sprocket fine but while the chain is coming out of the sprocket is when the teeth on the sprocket keep clipping the side of the chain causing it to "pop" and almost derail.

    Hope that helps.
     
  7. RedB66

    RedB66 New Member

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    So what your saying is just remove the pin and ball bearing and then thread the tool on and it should just pop off?

    No!! you have to remove the retaining nut (and washer) first.
     
  8. psprat496

    psprat496 New Member

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    And where is the retaining nut? This is really confusing since I've never done this and have no idea what to do. I don't want to mess it up or anything but all I see when I take off the clutch cover is the sprocket with the pin sticking out.
     
  9. RedB66

    RedB66 New Member

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    If you look at the sprocket..... in the center of it is a nut.

    PM me if you would like to me to call you.
     
  10. psprat496

    psprat496 New Member

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    I just sent the PM
     
  11. Creative Engineering

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    Yes it does...The engine sprocket is not formed correctly! It has nothing to do with 410 chain or 415 chain.

    The new kits with "so called" 410 chain really aren't! It is actually a bastard size that they are making for the kits.

    415 measures 3/16", (.187") between the chain plates...410 heavy duty measures 1/8", (.125), between the plates.

    The bastard measures .155 between the plates.

    Jim
     
    #11 Creative Engineering, Apr 17, 2010
    Last edited: Apr 17, 2010
  12. psprat496

    psprat496 New Member

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    So they're just putting these smaller chains into these new kits without any changes to the sprocket?
     
  13. Creative Engineering

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    Possibly! The Grubee kits that I've had here at the shop did have a thinner engine sprocket.

    The bottom line...you will need to check it out with calipers...measurements tell all!

    Jim
     

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