Why did all the centrifugal clutch kits disappear?

Discussion in 'Motorized Bicycle General Discussion' started by zestyzebra, Mar 24, 2017.

  1. zestyzebra

    zestyzebra New Member

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    When I was getting my kit a few months back I was going to get one with a centrifugal clutch included but by the time I ordered it was out of stock. I figured I would just buy one later since there were a bunch on ebay for <$40. Now I don't see any! Even the usual sellers (gasbike, spookytooth, etc) have them listed as out of stock. Is there some issue with the supply from china?

    I can find the actual clutch with no problems but the modified cover is no where to be found. http://www.ebay.com/itm/Centrifugal...ash=item54298a34f8:g:oKEAAOSwJ7RYTv4t&vxp=mtr

    Anyone know if we will be seeing these things again?
     
  2. ultralight01

    ultralight01 New Member

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    The four stroke kits are all centrifugal. I've never heard of a 2 stroke kit with a centrifugal clutch.
     
  3. quik225

    quik225 New Member

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  4. ultralight01

    ultralight01 New Member

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    Get a four stroke kit. That seems to be last option.
     
  5. dogcatcher

    dogcatcher Member

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    Check with the go kart suppliers.
     
  6. ultralight01

    ultralight01 New Member

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    They don't have any adapter plates.
     
  7. crassius

    crassius Well-Known Member

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  8. Agreen

    Agreen Member

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    It's hit or miss. Check eBay once a week, as they will come and go. I have one. I gotta be honest thoguh, it kind of sucks.

    It chatters, it doesn't pull well from a stop, and you have to disassemble it to lubricate the sprag bearing. There was a youtube video where one Australian did a modification where you could fit a WD-40 straw in to spray lube it, but we're smarter than that and understand that WD-40 is not a bearing lubricant.

    If you do lubricate it, you will have to fight the oil sling that ends up on the clutch shoes. Then it chatters even worse.

    The worst part is that it doesn't even fit properly without EXTENSIVE modification. Give me a minute, I'll find a link for you that spells out my hardships.
     
  9. Agreen

    Agreen Member

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    http://motorbicycling.com/showthread.php?t=60645&page=2

    I posted page 2. It sort of skips to the good part, but if you want to read through all the troubles, back up to the beginning. I feel as though I may have spoken a little too soon when I said "best modification ever" and "definitely worth it". It's not horrible, it's just a lot of extra work.
     
  10. zestyzebra

    zestyzebra New Member

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    Wow that sucks, it's strange that they are only posted sometimes. Is it worth it overall? How many hours of extra work do you think it is to make it work and can it be done with limited tools? (electric drill, dremel, hand tools but no big power tools) What mods do you suggest are worth it? I am having trouble figuring out what is usefull and what is overblown. I cant really port effectively since I had to build a strange intake manifold because of frame issues and I am not really sure how much of a performance boost a working long expansion chamber would give relative to how many problems it would cause. I think a shift kit would be great but they are so expensive.
     
  11. ZipTie

    ZipTie Member

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    I bought a centrifugal clutch a couple of months ago on ebay, They are only like 10 bucks and free shipping. They come and go as when I bought mine there were like 10 people selling them. I haven't installed mine yet so I can offer no advice. I thought yours was working pretty well Agreen? But yep not one listing on ebay currently.
    I'm installing a auto wet clutch 2 stroke now called the Bullet train and hiding all the wires
    also. Some People rave about the engines smoothness and the electric start etc.
    here's a link to the build.
    http://motorbicycling.com/showthread.php?t=62700
     
    #11 ZipTie, Mar 25, 2017
    Last edited: Mar 25, 2017
  12. Agreen

    Agreen Member

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    The Aussie spaced his cover with 5 or 6 clutch cover gaskets that he glued together. Much easier, but I haven't been able to find just the clutch gasket for sale. So you'd have to buy the gasket kit... 5 or 6 times.

    What I did do (may be within your ability?) is a poopoo pipe. I custom built mine, and got very lucky. Somehow it gave it an expansion chamber effect, so it must have been sheer luck. Anyway, the point is that a good expansion chamber exhaust will do wonders.

    Another thing is porting. I know you said it wouldn't be easy, but if all you do is pull the jug and match the transfer ports, you will notice significant power gains throughout all RPM.

    My next project may be unlocking the potential of a reed valve. I'd like to see if it does anything. So far, I've tried 3 different carbs, and I found out that some may move the power band a little, but you always end up losing power somewhere. Stick with the NT carb (the one it comes with)

    Almost forgot. The pull start. I got one of those, read a bunch of reviews and got scared, but tried it anyway. The good ones have a plastic grommet where the rope goes through the case. Some don't, and the rope will break after like 3 pulls. Mine has lasted for over a year, and I love it.
     
  13. s1rvr15

    s1rvr15 Member

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    A little on the pricey side, but if you want a centrifugal clutch, you can always buy one of the BT-80 electric start kits from Bikeberry, I have one and absolutely love it.
     
  14. Agreen

    Agreen Member

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    Yeah, it did for about 6 weeks. You have to continuously lubricate the sprag bearing, which requires some disassembly... which is ok, but it eventually works its way to the shoes. No matter what I do, it still ends up on the shoes. And once they're contaminated, it's done. Chatter city from there out. It's not like I slathered it with grease, I always use a small application every other fill up (about 150 miles). I wipe all the old grease out, clean everything with brake cleaner, apply a tiny amount to the shoes. Next greasing, it's only on the shoes and not on the sprag. And no, the seals are in good shape.

    I just figured it could have been thought out a little better. Maybe a sealed bearing? I dunno. I'm just not that happy with it. I bought a HF 79CC 4 stroke that I'm planning on swapping in. Hopefully I can get a good centrifugal clutch to go on that.
     
  15. Potato_In_Exhaust

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    Why do you guys feel the need for a centrifugal clutch? It's just added cost with zero benefits.
     
  16. ZipTie

    ZipTie Member

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    No clutch on a MB is without cost and some maintenance. Less pedaling to get going I would imagine is one benefit, as I've never had on a MB I wouldn't know. I haven't had one since I was a kid on my first minibike, never had a issue with it except for the constant annoying ringing bell sound. I then graduated to a 4 speed Yamaha mini Enduro and loved the clutch. I'm building a oil bath wet auto clutch BT 80 also.
    http://motorbicycling.com/showthread.php?t=62700

    I bought this ne fangled engine it for the novelty of the electric start not the auto clutch, however the auto clutch will be handy if someone who has never worked a clutch wants to ride with me they can hop on the BT 80. Lots of young people have never worked a clutch in their life as auto transmissions take over almost 100 percent nowadays.

    Agreen I want to build a 4 stroke this summer with the 79cc also, people swear by them as very trouble free.
     
  17. Agreen

    Agreen Member

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    I think it'll be fun. I most definitely don't want to build the "cookie cutter" example with the universal mount bracket. Those just make it look so... utility. If it's going to have my name on it, (and I know you're nodding your head right now) then it has to look the part!
     
  18. ZipTie

    ZipTie Member

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    Right on Agreen. I agree those cookie sheet mounts are pretty bad.
     

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