Bleeping autoclutch........

Discussion in 'Whizzer Motorized Bicycles' started by RdKryton, Jun 22, 2009.

  1. RdKryton

    RdKryton Active Member

    Well I have tried every trick that has been posted here. This clutch is not like a fine wine. It does not get better with age. This clutch is aging like milk. I have removed the glaze on the shoes to the point of better that 95% shoe contact. I have sandblasted the drum to remove the glaze there too. I can hold the handlebars and roll the throttle all the way up to over 6k without touching the brakes and the bike just sits there. Almost no pull at all. If I look at a hill in the distance the bike slows down. It is not rideable unless the ground is flat. I have talked to Q and I am going back outside to pull the clutch off and send it to him as soon as the waves of heat radiating off it stop killing my lawn. I wish I could go back to the slip clutch but with the rear drum brake it will be difficult. I may just put another clutch lever on the left side of the handlebars anyway. I wanna ride........


  2. WZ507

    WZ507 Member

    Bleeping autoclutch

    Jim - That's an unusual autoclutch story, but we all feel your pain. I've never heard of having essentially full shoe contact and getting no engagement, but I applaud you for going to the 6000 rpm full throttle operation to emphasize your point. If that didn't hook it up, nothing ever will. It's strange that you could get to almost full shoe contact and get essentially no driving force out of it. Maybe you've got a set of mammoth springs that never release the shoes. I suspect that breaking the glaze and creating more surface area on the drum is counterproductive to your goal, as the higher surface area of the drum means reduced surface area of contact for the shoes (only the peaks of the drum surface contact initially).

    It's a shame that something so simple as a centrifugal clutch could be aborted so badly by Whizzer (it would be an extreme stretch to say that anyone with any knowledge of mechanical engineering designed it). As always we're eager for the rest of the story.

    In the mean time move that bike onto the garage apron, as those white thermally induced sod burns can be ugly in a nice lawn.
    Last edited by a moderator: Dec 15, 2015
  3. RdKryton

    RdKryton Active Member

    The funny thing about this it used to be better. Not great but I used to be able to pull this one hill at over 25 mph. Now I was pedaling for all it's worth to clear the hill at 10 mph. The hills around here are just enough to make it unrideable and it's making me an unhappy camper. I love this Whizzer but the autoclutch is getting worse every time I ride it. I'm not trying to bash anyone or the Whizzer company. I'm just disappointed because I finally have some time to ride but I can't.
  4. WZ507

    WZ507 Member


    You may not want to speak unkindly about the Whizzer autoclutch, but the truth of the matter is, they deserve it, for the simple reason that, in my opinion, the majority of the clutches sold were defective. My first one had about 500 mi on it before the needle bearings etched deeply into the soft cast shell. Called Whizzer and they said that would be too many miles to fall under warranty (it's expected to fail in 500 mi?). On the next autoclutch I purchased, which also had a soft cast iron bearing surface (filed easily), I installed the inner bearing race (sleeve) to correct the soft material issue only to find that the casting wasn't evenly filled during the pouring operation, and that there was a wide low unfilled void on the internal vertical surface of the shell that resulted in the clutch being out of balance which in turn caused excessive vibration. The solution was to drill and add metal to the shell to balance it. So I'm 2 for 2. I've yet to ever hear from anyone that had a properly hardened center spindle on the shell, but I don't doubt that at least one might have somehow been created along the way. Of course back when I mentioned this at the time I was the only one that had ever had such a complaint (that sort of summarizes the majority of my mechanical experience in life, where way too often I'm the only one that's ever confronted the peculiar problem of the moment - right)! Sound familiar?

    So that's my experience with Whizzer autoclutches. It irks me no end that someone would produce a defective product. Shame on the design group for being clueless on both mechanical design and compatibility of materials (bearings, races, and friction materials), shame on the manufacturer for building a defective part, and lastly shame on Whizzer for passing it off on the public as a functional part. That in my book is dishonest. If you've got a bad part, you scrap the defective lot or rework it, correct the design or manufacturing deficiency, test the new product to verify that it functions, then offer it for sale. But given the other design deficiencies all over the engine why would we be the least bit surprised by the clutch issue? After all, who do we think we are expecting a good part when we pay a fair price for something?
    Last edited by a moderator: Dec 15, 2015
  5. wes

    wes Guest

    "in the mean time move that bike onto the garage apron, as those white thermally induced sod burns can be ugly in a nice lawn" Thanks for the belly laugh!! I add to the POS autoclutch. can't tell tell you how many hrs. i spent on it. Now i'm a very happy slip clutch owner. I have disc brake front and rear. my rear brake is on the left and the lever is used as a drag brake with my thumb and the clutch lever is in the standard brake position on the front of the bar. It can be done and becomes natural. i always use the front on the right, on racing bicycles and motorbicycles. w.
  6. KilroyCD

    KilroyCD Active Member

    I've never had the desire to switch to an autoclutch. My NE5 has the slip clutch, and I'm quite happy with it. But then again, I've always preferred manual clutches, as every car I've bought has had a manual transmission. Call me old-fashioned, I guess...
  7. Hal the Elder

    Hal the Elder Member

    HEY JIM:

    Get a no-nonsense Slipper and a Worksman rear wheel with a SHIMANO coaster brake!

    I installed Worksman wheels front & rear on Oscar, my 2005 NE5. Nice husky wheels, with 0.120" spokes!

    I paid my dues with that crummy auto-clutch, removing the glaze from the shoes every 100 miles or more!

  8. alberndt

    alberndt New Member

    crummy clutch

    I can vouch for 2 things, put a set of workman rims on my EZ build and are built like a tank, removed the auto clutch from my whizzer and went back to the slip clutch and happy as a clam, so much easier starting. Now I just need to start fine tuning the engine a little more. Best thing that I did, I had purchased the pulley years ago from memory lane and never used them, went to a machine shop and he turned a new bolt and spacers to mount-$60.00 in the cost of the conversion.

  9. KilroyCD

    KilroyCD Active Member

    I have Jim's old slip clutch pulley for him to reconvert his back to slip clutch, but he'll have to figure a way to work around his drum brake. He has a brand new set of Worksman wheels on his Whizzer already...
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