Centrifugal Centrifugal Clutch Kit Heads Up And Help Needed

Discussion in 'Transmission / Drivetrain' started by Porkchop, Apr 6, 2010.

  1. Porkchop

    Porkchop Member

    I have info and questions on the centrifugal clutch option. First of all, I used a pneumatic file and file down the pins, pegs or what ever they're called, that protrude through the clutch as instructed. No problem there, except it was a wasted effort. I went to bolt on the new clutch cover that came with the kit and it would not fit properly. A big gap between the engine block and the cover. I cut cork gaskets to take up the slack. I discovered later that the side walls of the new cover were not as wide as the original cover. The original is about 5mm wider. I have not dealt with this engine in several months, so I don't remember all the dimensions to be exact. The new cover is bottoming out on the clutch and will not mate up with the engine block leaving that wide gap. I decided not to use the gaskets that I cut. To me that is unsatisfactory and unacceptable. Does anyone know of a fix or where I might be able to get a deeper clutch cover. Check out the attached photos. No. 1 & 2 show the filed down pins, No. 3 shows the new and original clutch covers side by side. The one on the left is the new cover. I think you can see in the photo the difference in the side wall depths. I have not contacted the vendor that I bought the kit from. It is one of the reputable ones on this forum. I'm curious if this is a normal thing with the centrifugal clutch kits. Thanks for any serious replies !

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    Last edited: Apr 6, 2010

  2. Dilly Bar Rob

    Dilly Bar Rob Member

    That's the way those covers are Porkchop, they are indeed narrower then the original. It should go on and not hit the clutch with those pins filed, if it doesn't then it's most likely the clutches fault (ie it's sticking out too far on that engine, doubt you can do anything about it), not the covers.

    I got that fist cover on no problem, but the second one (the smaller one that goes on the first over the cent. clutch) had the same problem - it would hit the clutch bell no matter what, also needed like a 5 mm gap to work.... This was ONE of the reasons why I gave up on the centrifugal clutch setup, The vendor (zoom) was helpfull but that doesn't help when the parts don't fit (well).

    I will measure the depth of my cent. clutch cover (still have it i think) for you later on today just so you can rule that out (but i'm positive that it's not the covers fault).

    Is this engine on a bike right now? If it is I say go test ride the bike with the cent. cluch on and the cover off FIRST, before trying to iron out the cover issue, just so you can find out if it really is worth the effort...

    Dilly Bar Rob

    P.S. - didn't you ask about the cent clutches some time ago? I Remember replying to someone and I think it was you, not sure
  3. arkives1

    arkives1 Member

    centrifugal clutch kit-help needed

    Like Dillybob, I got the first cover on with no problem, and when the second one wouldn't fit, I cut a hole in a piece of plexiglass to be a little bidder in diameter than the bell housing on the c-clutch. I then cut the circle to match the diameter of the cover where the screws attatch it to the engine, when that was done, I drilled holes for the screws and mounted the cover with the plexi glass shim between. I did this on two engines from Zoom and they have lasted for months and seem to handle the engine heat ok. Dilly gave you good advice about trying it without the cover to see if you like it first. I find that my take off speed is slower with the centrifugal clutch but it's a real help in city riding where we have a lot of traffic lights and stop signs. My bikes will still go faster than I want them too if given full throttle.
  4. Porkchop

    Porkchop Member

    Thanks for the replies guys. If you look at photo #3 in my original post, that's the cover that will not fit and is hitting the clutch. or maybe a better term, flywheel. I've had this engine for about a year now and have never mounted it. I do recall about 5mm difference in the depths/widths of the 2 different covers. I have thought about getting a machinist friend to mil a spacer out of plexi glass or aluminum. And yes, I recall posting about centrifugal clutches in the past, but I think they were replies rather than questions. Don't remember exactly. I wish vendors would not pass this stuff off to us knowing they don't work/fit. I'm mechanicaly inclined enough to make it work but it's not that important to me. I have a strong feeling my next motored bike will be a 4 stroke 50cc rack or frame mount.