Whizzer centrifugal clutch

Discussion in 'Whizzer Motorized Bicycles' started by Squeakit, Apr 1, 2008.

  1. Squeakit

    Squeakit New Member


    I've been thinking about installing a centrifugal clutch on my '98 Classic with NE5 upgrade, although the standard belt clutch works fine. Just getting a little tired (lazy) of holding in the lever when I'm going slow or sitting at a stoplight. Are the units available from Whizzer the latest and most reliable? I've seen some negative comments about centrifugal clutches in the past and I don't want something that's going to create problems. Can you use the standard slotted belt guard with the new clutch? Any comments and/or advice about centrifugal clutches would be appreciated. Thanks.

  2. RdKryton

    RdKryton Active Member

    Those are great questions. I have also read some negative things about them but have also heard great things about them. I have been thinking about the 50mm clutch for some slower speed operations but need to know the answers to the questions you asked.

  3. KilroyCD

    KilroyCD Active Member

    I've been having the same thoughts, but my reason for considering one is due to Carpal Tunnel. It just hurts holding that lever down for any length of time. I think you'll get the answers to your questions here. Some of the guys on this board are true Whizzer specialists.
  4. Quenton Guenther

    Quenton Guenther Motored Bikes Sponsor

    Hi Everyone,
    Whizzer has offered several versions of the automatic clutch, and a few companies have also offered their own versions. Just like any new product some worked better than others. I will try to supply a little infromation to help. In 2001 Whizzer offered an automatic clutch on their 24" Pacemaker II, but had very high ratios [or low ratios depending on how you look at it]. Because the clutch caused the bike to take off slow, and the motor was restriced, many didn't care for it, however it remains one of my favorite options on my modified NE motors. It was the clutch I used on my record setting 1999 Whizzer [68MPH], and is still the clutch I use on my wife's 2001 Pacemaker II. Because my motors produce so much power, the bigger clutch works well for "crusin". The 2001 clutch was very large and heavy [someone once told me they needed a fork lift to move it, ha ha]. The next clutch to arrive was a replica of the "vintage" autoclutch modified to fit the new edition Whizzers and was produced in Ohio. Sadly it didn't work out well, cost over $450.00, and I watched several snap off, due to vibration, and roll down the road. Next a company in CA made a version, but required special mounts, had no provision to keep the belts tight [no tension spring], and required constant adjustments. And worst of all the company that made them doesn't take care of it's customers because I have 2 of them laying on my workshop floor needing needle bearings [a constant & serious problem], and for the last 18 months they have promised me to obtain & send the needed bearings [I would have had just as much luck "talking to the wall"]. Whizzer was working on a new design at the same time, and I had great luck with the early versions, but didn't like the ratios. Whizzer changed the ratios to match the manual clutch and offered the new version, but some complained about the ratios because their motors were restricted. Since the Whizzer doesn't have a transmission a balance must be reached to allow take off and a resonable top speed, but many requested a different ratio, so Whizzer offered them in 2 versions, a 50MM, and the original 90MM output hub. It wasn't long before some complained about poor top end using the 50MM hub [duh!], but were thrilled about the power at take off. Whizzer then offered an additional version using a 70MM hub [now stock on the new Ambassador], of course the smaller output pulley lowered the top end somewhat [44 MPH @ 6500 RPMs]. Although I have never had a defective clutch [made by Whizzer], I have seen a few with minor issues, mostly with the bearings or the bearing race. As with all products offered by Whizzer they are always trying to improve their products, and have made several changes during production, in fact I am presently modifying a few with yet another new idea to improve durability concerning needle bearings turning at very high speeds for my special high output motors. Whizzer is also working to improve the clutch, but is heading in a different direction by using some "caged" bearings instead of all needle bearings, but is still in the testing stages.
    Now a few comments on how the clutches engauge, many think the clutch should work like a "go cart" and lock all of a sudden. My tests have shown it to be a bad idea to lock the clutch way below the power band of the Whizzer motor [1800 to 2200 RPMs]. Even my high powered motors don't take well to a sudden lock at lower RPMs. The current clutches offered by Whizzer "slide" into lock, which allows the motor to develope the needed power during the enguagement process. In a recent test using identical motors, and the newest clutch from Whizzer and a unit [guts from a Comet go cart clutch]that locks all of a sudden, the Whizzer clutch EASILY outperformed the "Comet" version. In a 1/2 mile run the Whizzer clutch bested the alternate version by at least 10 bike lengths every time. I then swaped the clutches on the 2 bikes and ended up with the exact same results. Last year at Dawson Springs, KY, my NE powered 1950 Sportsman managed to pull "wheelies" as the Whizzer clutch gluided into full lock, and easily won the "dirt drags" against every Whizzer entered. I was the only entry using the Whizzer clutch and some were even using the comet torque converter.
    Hope this information is helpful,
  5. KilroyCD

    KilroyCD Active Member

    Quenton, that was a lot of very good info. Thanks for posting it. Now I have to decide whether to get a centrifugal clutch or get my carpal tunnel problem taken care of! :lol:
  6. RdKryton

    RdKryton Active Member

    Both... I'm already half way there.

  7. RdKryton

    RdKryton Active Member

    Hello all.
    Rather than start a new thread I though I would post my recent experiences with a new 90mm centrifugal clutch. I a word NICE. It changes the whole behavior of the bike. It makes starting easier (at least for me) and the bikes low speed manors are great. It is now very easy to handle at low speeds. The clutch does not lock up real fast which is what I prefer. It just sides into lock at about 2600-2800 RPMs but when it does lock up hold on. See post #4 of this thread. Quenton explains it better than I can. It is just so much more fun to ride now. Not that it was not fun before but I like it a lot more now.
  8. photoguy25

    photoguy25 New Member

    Hopefully I am the correct thread. I have a 2008 Whizzer NE5 with an auto clutch. I just purchased a replacement auto clutch. Any help would be appreciated in step-by-step instructions for installation before I screw something up. Thank you.