CVT Anyone Using A Comet Torq-A-Verter?

Discussion in 'Transmission / Drivetrain' started by 5-7HEAVEN, Feb 22, 2009.

  1. 5-7HEAVEN

    5-7HEAVEN Guest

    Working on "BOB", my 6hp push trailer.

    After careful measurements, I find that the Comet TAV should clear the block of my 6hp Robin overhead cam engine by .020"!!

    The TAV clears the trailer and lines up with a jackshaft. After the trailer's dropouts are widened from 100mm to 135mm, the 16" BMX mag wheel and freewheel sprocket should fit well.

    My question is if anyone is using this Comet TAV on their bike, trike or trailer?

    Check this out. It even gives the formula for gear-ratio selection.
    Last edited by a moderator: Feb 22, 2009

  2. Alaskavan

    Alaskavan Guest

    I think Zomby tried them for a while, and had problems with burning them up. That being said, my trike has an internal CVT and it seems to be doing fine. Comet also makes CVT's for snow machines. I haven't heard of any probs with them.
  3. 5-7HEAVEN

    5-7HEAVEN Guest

    Thanks for responding.

    What kind of engine do you have and how does your internal CVT work?
  4. cvt

    I wish that these would work on a Whizzer.... Whizz uses the flywheel as the magnito or I would throw it away & replace it with one of these. Just my jaded opinion of the Whizzer auto clutch though. It truly Suxxxx. Ask olddude, he uses these on his 6.5 Techumsies, & likes them a lot.
  5. Alaskavan

    Alaskavan Guest

    The internal CVT is on my Lifan. As for how it works, I assume it works just like a Torq-A-Verter, but I don't know for sure. I'm not planning on looking at it 'til the motor breaks.
  6. Gungatim

    Gungatim Member

    I have used these before on go kart's. I believe the ratios go from 2.7:1 to .9:1 overdrive on the TAV. I have had good luck with them, never burned one up, but you do need to keep it lubed and maintained (as with any clutch). I did some calcs, with a 60tooth sprocket, you should be able to do close to 40 in high, but have a nice 13.5:1 gear ratio in low. I think the cost is what keeps alot of people away from using these more.
    Last edited: Feb 23, 2009
  7. 5-7HEAVEN

    5-7HEAVEN Guest

    Thanks for feedback, guys.

    Gungatim, 40mph is exactly the speed which I intend to limit "BOB", my push trailer.
  8. buck

    buck Member

    I am running a Comet TAV2 converter. So far over 600+ miles and no problems. I just did a pre season inspection of the torque converter. No wear, everything tight, no noticable wear on the belt. I looks as good as the day it was installed. Just waiting for the weather to break.
  9. 5-7HEAVEN

    5-7HEAVEN Guest

    buck, which engine and bike setup are you using. What is your sprocket gear ratio, and do you have 6" or 7" pulley?:detective:
  10. mabman

    mabman Member

    Look on eBay for one.
  11. 5-7HEAVEN

    5-7HEAVEN Guest

    mabman, I'm lurking there now.:whistling:
  12. graucho

    graucho Active Member

    Comet TAV2 converter. Sounds like a lot, but Ive used at least 20 of them in the past. Smooth and quiet. Nice engagement. Quick.

    Attached Files:

  13. 5-7HEAVEN

    5-7HEAVEN Guest

    graucho, which gears and pulley should I use?
  14. graucho

    graucho Active Member

    Hey 5-7

    Here is the link where I bought everyone of them. They give a great explanation twards the middle of the page how the drive and overdrive works.

    Ive always order the stock tav2 30 series with the 3/4" bore 10 tooth sprocket. for the #41 chain.
    My bikes always weighed between 140 to 185 lbs and they had great get up and go.
    I fluxuated between 44 to 72 tooth rear, but I think 60 tooth (like Gungatim stated) you should be able to run at 40mph strong.

    I also used the GP-730A Lubricant they sell and it works super! (also explained at the bottom of their page)

    Hope this helps. graucho

    Attached Files:

    • tav2.gif
      File size:
      12.6 KB
  15. 5-7HEAVEN

    5-7HEAVEN Guest

    Thanks for the valuable information, graucho.
  16. buck

    buck Member

    I am running the TAV2 torque converter using #35 chain to a 60 tooth rear drive sprocket on a pusher trailer. The drive wheel is from a Honda Z50 mini bike. This also gives me the option of additional braking power. The sprocket was a fairly easy swap with the Honda wheel. I bought the sprocket which had the right center hole from an Ebay seller, then just drilled the bolt holes and away i went. Gives me a nice cruising speed of around 20mph and a top speed of around 25. I am using a small briggs type lawn edger motor for power. An easy way to check your wheel size with the sprockets needed to achieve the right cruising speed is located at The speed calculator has saved me many hours of trial and error.
    Last edited: Feb 24, 2009
  17. RidingJesus

    RidingJesus New Member

    Does your TAV2 ride smoother than a go kart clutch would?

    I may consider making a trailer for hauling my stuff, and I want a smooth and not so shaky takeoff, so my stuff doesn't get damaged or fall off.
  18. loquin

    loquin Active Member

    The comet 340 might be the best 'fit' for our application. The engine rpm 'adjustment' range is higher on the 340 than with the others.

    According to an email that I received from one of the engineers at comet, with new belts, they transfer between 90 and 95% of the power to the driven pulley. As the belt wears, the efficiency drops, so, keeping them dust free & clean should help.
  19. DetonatorTuning

    DetonatorTuning Active Member

    wow thanks graucho, buck and Lou for sticking with this thread and providing the great links.

    i have a question though.

    in the comet lit. that Lou linked is the statement........

    "2.5:1 at engagement up to .8:1
    overall ratio 3.16:1"

    at which end ( low or high speed ) is this 3.16:1 overall achieved and how is it explained.

    if it's at the high speed end then there must be some known value of internal reduction involved that would mean that the full overall low speed ratio is more on the order of 6.32:1 at engagement.

    can you help me understand this ?

  20. DetonatorTuning

    DetonatorTuning Active Member

    who has a picture of the back ( output shaft side ) of a comet ?

    i'd like to see both engine and output shafts if possible.