Need easier way to start 49cc cag motor

Discussion in 'Motorized Bicycle General Discussion' started by Chainreaction, Feb 15, 2015.

  1. Chainreaction

    Chainreaction New Member

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    I have cancer and doing chemo so I am kinda weak. I have managed to start my new bike a few times but most of the time I can't spin it fast enough. Damn thing has some serious compression for 49cc. I want to go riding!

    So I have thought of maybe an ignition that is hotter and fires better when turned over slowly. But I think an electric start would be best, the only one I have seen mounts on the output shaft side between the motor and the clutch, these motors are wide enough as it is, I don't need even wider. One that goes where the pull start goes would be ideal. Or maybe use a cordless drill, hate to buy one and find it not strong enough though. Or some starter or motor off of something else that I could adapt to work.
     
  2. frank66

    frank66 New Member

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    my derbi bullet is electric start and ipaid 500 bucks for it. hope you find something. whats the cag on? bike?
     
  3. Flyman

    Flyman New Member

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    Do you have the strength to pull start one. Amazon has pull starters for them.

    I hope I helped Fly
     
  4. curtisfox

    curtisfox Well-Known Member

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  5. Chainreaction

    Chainreaction New Member

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    That is what these motors come with, pull starters. And that is the problem for me, they are too hard for me to pull fast enough.
     
    #5 Chainreaction, Feb 16, 2015
    Last edited: Feb 16, 2015
  6. Chainreaction

    Chainreaction New Member

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    I don't want to spend that kind of money and I want to stay with this motor.
     
  7. Chainreaction

    Chainreaction New Member

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    The starter motor listed for this motor is the kind that goes in between the motor and the clutch, makes the motor too wide.
     
  8. Davezilla

    Davezilla New Member

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    I know a little about teh Cag engines and their high compression... I remember back when they were really popular the plastic starter pawl was that engine's weakest link so one would have to carry a few spares everywhere ya went until they began making an aluminum pawl that wasn't so fragile.

    I'm just wondering if there's enough room on top of the head to drill and tap threads for a decompression valve like some mopeds used to use... Maybe try looking up decomp valves on treatland's site www.treatland.tv , ebay, or aliexpress to see if anyone makes a really small one that could fit on a CAG head.
     
  9. Rich909

    Rich909 New Member

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    Hi Chainreaction --

    I've been thinking about something like this myself, based on my experience with a 4-cycle Troy-Bilt trimmer with 'JumpStart' that I have learned to love. Recently they have offered an attachment for use with a power drill. Here is a link: http://www.troybilt.com/equipment/troybilt/string-trimmers/jumpstart%E2%84%A2-engine-starter-bit-jumpstart-drill-bit at about $10.00.

    You can get an 18v 3/8 cordless drill from Harbor Freight for about $20.00 with an easily found coupon, that I think might be able to do it.

    If corded is OK, you could get a 1/2" HD drill from them for about $35.00 that I am pretty sure would do it. Otherwise get a Troy-Bily JumpStart see: http://www.troybilt.com/equipment/troybilt/string-trimmers/jumpstart--engine-starter for about $30.00. However, if the 18v 3/8 H-F drill would do it, you might find it handy for a bunch of other things. I've got 2 or three of them and have had good a experience.

    If this strategy is worth a try, I think all you need to do is pull the recoil starter and have someone weld up a crankshaft nut with a JumpStart socket in it. Alternatively convert the JumpStart hex drive to standard 1/4" drive and build a 1/4" drive socket to fit the end of the engine crank.

    HTH.

    --Rich
     
  10. curtisfox

    curtisfox Well-Known Member

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    Sorry thought it was a rewind starter.................Curt
     
  11. maniac57

    maniac57 Old, Fat, and still faster than you

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  12. Davezilla

    Davezilla New Member

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    Now that's a really cool idea but wow... did you see the price tag on that? That would be ideal for a CAG engine that already doesn't have a lot of dome area on the head.

    I bookmarked it tho in case my sportster needs it after I install that set of Firebolt heads I got waiting for a few more goodies... like a Hammer Performance 1250 kit as well as sending the heads to them for some serious CNC porting and a 30 degree squish band etc... Pretty much everything it'll need to make about 110hp or more.
     
  13. Intrepid Wheelwoman

    Intrepid Wheelwoman New Member

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    At that price it must be a gold one ;)

    Seriously though wouldn't a reasonably good battery powered drill with a socket adapter work as a way to start one of these engines. I don't own a CAG engine myself so I can't test the idea, but it seems to me to be simplest way of going about it. Surely somebody here who runs a CAG engine could try it out and see and report back.
    If this method is successful the drill could be carried in a saddlebag when it isn't being used.

    And Chainreaction, you hang in there Ok. I've got you on my prayer list.
     
    #13 Intrepid Wheelwoman, Feb 16, 2015
    Last edited: Feb 16, 2015
  14. Davezilla

    Davezilla New Member

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    I'll test it out on the CAG engine I got at the shop... it's not mounted in a bike or anything right now but I can take the pull start cover off and see how easy or practical it would be.... These little engines have a ton of compression for their size, but I'm thinking it might work as long as there's a strong enough bolt or nut on that end of the crank. It may still need a little bit of decompression like maybe tapping in a really small ball valve into the head.
     
  15. Theon

    Theon New Member

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    I drilled and tapped an angle fire head to take a chainsaw decomp valve once.
    Would likely be possible on a stock CAG top end?
     
  16. curtisfox

    curtisfox Well-Known Member

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  17. Chainreaction

    Chainreaction New Member

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    If it wasn't a one piece jug/head I would consider it.

    Yeah these cags have serious compression for their size. I had a $500 Stihl chainsaw that pulled easier than these suckers.

    @ Intrepid: A DeWalt 18V might be strong enough to turn it over but I doubt anything less would do it without gear reduction.
     
    #17 Chainreaction, Feb 17, 2015
    Last edited: Feb 17, 2015
  18. Chainreaction

    Chainreaction New Member

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    Sweet!, that is exactly what I need. Thanks! I am going to look into a starter/alternator for pull starter side later but this is exactly what I need now. I have a HF cordless that should work fine, have mill/drill & tig to mod whatever.
     
  19. Davezilla

    Davezilla New Member

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    Yup... most the CAG engines have the one piece jug and head like most the chainsaw engines, there is a "high performance" kit that has the separate jug and head but they're also a bit pricy for what you get, and all they really are is a stock jug with the head milled off. Not too bad a deal if building a bike and getting a new engine set up this way but a bit too pricy to be practical to convert one...
     
  20. Chainreaction

    Chainreaction New Member

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    Actually that TroyBuilt piece isn't what I need, I assumed that it was gear reduced which it isn't, gear reduction is what I need in order to use a cheaper cordless drill.

    So back to square one, and easier way to start the mighty cag. Maybe take the starter that is made for these that fits on the left hand side and modify to work on the right hand side? That would reverse the starter direction, electronics is not my thing, maybe just reverse polarity?

    Or come up with some kind of kick starter design, put a ring gear on the flywheel.
     
    #20 Chainreaction, Feb 26, 2015
    Last edited: Feb 26, 2015

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