CVT CVT's and Comet drivelines

wow this is a whole new way to look at tuning CVTs i come from a sled(snomachine, sno go, snomobile for the unintiated) background where we tune them to use the whole powerband of the engine, 2 or 4 stroke. are these smaller CVTs completely differant than the comet setups i run on my RMK? im wanting to build a functional boardtracker setup, i want it to look like a old board tracker but was contemplating going CVT so that it has the speed/power to back up the look of a boardtracker, i want to be able to at least hit 50ish preferably more so i can hang/outrun all the kickers that have sprung up around here. plus to me a replica of a race bike that doesn't back up its looks is kinda pointless, i might as well hang it on the wall at that point.

sheb
 
Mine has an internal CVT. I don't know how closely it matches the ones on snow machines, but I can do 50. Just did that on the way home from my beighbor's, 1/2 mile down the road. Ya' gotta have the horses. Oh ya', I don't look "od school", but if that's what trips your trigger....
 
compared to the tiny engines that are put on motorized bicycles, a snowmobile has virtually unlimited horsepower.

with typical MB engines, you're looking at about 2 HP available to use.
 
Hi All, I Thought I Was Way Ahead Of The Curve Building My Cvt With Freewheel On The Axle. I Did not Know A Thing About You Guys And Nuttsy Building Them Over Here Until A Few Days Ago. I Thought I Was The First To Assemble The Cvt On A Bicycle. I Honestly Did Not Know About The Developements Here. I Just Shows That The Mab Thing Is Growing And A Lot Of Parallel Thinking Is Going On. I Am Dellighted To Find More Info About The Cvt`s. I Ran Into A Deal On Craigslist. 3 New 49cc Motors With Cvts For $90. Each. Then Just Started Thinking How To Mount Them. I Used The 8mm 17 Tooth Sprocket That Came On The Cvt And Bought Various 8mm Wheel Sprockets For $10.50 Each. Have A 72 Tooth On The Rear Wheel. Very Happy With The Performance. They Mount To The Free Wheel Adapters That Screw On The Right Side Of The Rear Wheel. Just Remove The Cassette. Now I Have Found A $4. Adapter And Spacers To Connect Two Free Wheels Together For The Pedal Chain To Be Hooked Up. I Am Building Another Now With The Titan 4 Stroke. I Hope I Am Welcome On This Thread. I Go By "neat Times" On The Other Forum. Treewk Has Been My User Name For Years, As I Have A Tree Service For 30 Yrs. Neat Times Is A Name I Came Up With For My Offshore Boat, You Need A Boat Name For Identifcation When In Distress. I Have A Cvt Thread There, With Several Pics. I Hope To See More Of Cvt Progress. Ron
 
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Holy punctuation batman :)

Could you show some sources + pics of the freewheel adaptors etc? Very interesting! Could mount a freewheel + cassette this way...
 
Heath, Ordered Adapters Monday. Will Post Pics And Info When They Arrive. Yes You Could Add A Cassette If Room Allows. Have Purchased Support Bearing To Fit On Axle And Inside Adapter. But It Would Cost About $100. To Have Machine Shop To Make Adapter As I Wanted It. Now Am Waiting For Bb Repait Kits For $3.66. Will Only Use The Left Side Adjuster ( 1 3/8" 24 Tpi Od Bearing Adjuster Sleeve) To Connect Free Wheels . I Bought Some 1 3/8" Id X 1 7/8" Od Shim Washers From Mc Master Carr For Spacers. 10/$10.. Bought 2 Paks - .125" & .062" Thickness. I Think 1 Shim .125" Needs To Go On The Wheel First To Give More Freewheel Threads For The Bb Adapter Sleeve. It Seems Most Of The 3/8" Dia Axles Are Bent A Little. Therefore The Wobble Of The Support Bearing (from The Bent Axle) Would No Doubt Destroy The Threads In The Freewheels And The Coupler Sleeve. Need To Go To 1/2" Or Maybe 14mm Rear Axle And Then Use A Support Bearing. ( Then It May Be Bullet Proof). First I Bought Some Freewheel Adapters From Staton. They Are Cool, But A Bit Narrow. Purchased A Box Of Ten 3/8" Id X7/8" Od Sealed Bearings To Fit Inside The Staton Adapter. Put A Bearing Inside The Staton Adapter With A 3/" Bolt And Some Clamping Washers, Used Drill Press And A File To Remove The Flange. The Proplem With The Staton Adapter Is, Less Than 1/2" Of Threads. I Hope The Bb Sleeve Will Be Strong ( Thick) Enough. Have One Used Bb Sleeve Installed In Bike Now, Have To Disassemble It To Install New Mcmaster Carr Shims. Will Post Pics Later. Ron.
 
Here Is The Bb Kit. Just Using The Threaded Sleeve On The Right Side To Attach Two Freewheels Together. The Picture Of The Wheel With The Sprockets You Can See The .062" Between The Wheel Hub And Large Sprocket To Allow More Threads For The Coupler (threaded Sleeve From Bb Kit). Installed A .125" Spacer Between Freewheels ( Will Change It To A .062" As It Caused Extra Axle Washer Needed, Small Sprocket Rubbed Chain Or Seat Stay ). The Bb Sleeve Is Heavier Than The Used One From Bike Shop, Looks Like It Will Be Strong Enough. Now The Next Builds Will Be Easy. Ron
 

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That Is So Freaking Cool! :)

Its exactly what I want to do with my build (but with a 3/5 speed cassette rather than a single freewheel).

Amazing that a BB conversion kit does what you need perfectly. I'm off to find one now...

Hmm. I'm still not getting how you used the BB setup - the outside is threaded, but the inside is smooth (for the bearings) - Did you use this for the outside thread? How did you attach this to the wheel hub?

Am I correct in assuming that the freewheel is being used to join the two threads together? Now I get it :) I can be a bit thick somedays, thats a very clever way of doing this!

Are you going to keep the derailer as a chain tensioner and use the front derailer for a 3 speed?
 
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Heath, Yes, Use The Front Derailer For 3 Speeds On The Crank Sprockets And Use The Rear Derailer For Chain Tension And Keeping The Chain On The Rear Freewheel Sprocket. I Thought My Pedal Freewheel Was A 3/16", But Is 1/8" Bmx. (old Eyes!!!lol ) I Will Spin It In The Drill Press And File The Teeth Sides A Bit. That Way It Will Rust!! Oh Well, Whats A Girl To Do!! Ha Ha. I Don`t Think You Will Get A Cassette In There, Maybe Spread The Frame??
 
TREEWK,

fabulous piece of work, the double rear freewheel is brilliant, esp. coupled with the front three ring for gears. are you looking at putting closer count chain rings up front for more usable span ?

if i am understanding correctly, your rear hub is the screw on freewheel type and that you have put the BB adjuster sleeve on there, then , the freewheels on the adjuster sleeve with appropriate spacing ?

is the inner freewheel simply a toothed version and you match bored holes in the sprocket to line up with the roller valleys on it?

if you can keep the cvt working well you are going to have a really great bike.

steve
 
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