Jump to content

Recommended Posts

Any and all input on this subject is good information and will be kept here for reference. Once we have an official parts list, I am going to have Andi make it a sticky for ease of access and refer to this thread for the ups and downs of the task so anyone who wants to do this can do so with a knowledgebase at their fingertips.

So keep the thoughts and feedback coming!

I do think you will find it is almost impossible to find a 3 speed shifter that aligns with the gearing on these 3 cog freewheels, they use an irregular spacing as well as non-shifting teeth (no shift feed indentions). If yu do find one that works, it will typicaly only do 2 of the speeds correctly and one will be off. That is why using a friction shifter for 5-7 speeds works best. Like with mine, I have 7, 6 and then shift to 4 and back to 5 to get the final gear. I have 4 other friction shifters at home I am going to try at some point to see if the ergonomics are better but it works right now and I'm afraid to break it by trying out things.

Share this post

Link to post
Share on other sites

I finally purchased some parts for my 3 speed upgrade. It's been a frustrating journey trying to find parts that are both compatible and reasonably priced. Here is a list of the parts that I have purchased so far.

3 speed freewheel hub

Unique Bargains Bicycle Metal 3 Speed Threaded Scooter Sprocket Freewheel Repair Part

Shimano 105 RD-5701-SS Short Cage Rear Derailleur, 2 x 10 spd, Max 30T, Black


MTB crankset crank chain wheel BCD130 square hole 52T chainwheel with shield


I still haven't decided on a shifter. I think I'll wait until I get these parts assembled befor I go any further. I spent almost 2 weeks deciding on these parts and shopping up the best prices. BTW, I went with the shimano 105 because it is in the upper tier of the shimano line and I found an online store that had them on sale for $29. Much beter than the usual $60+ price I.ve seen elsewhere. I wanted to use a short cage derailleur and this fit nicely in my design scheme. The 105-5700 line is tried and true and well thought of by most bike aficionados. Be ware of the new 105-5800, it has an entirely different pull ratio than the standard 1.7. I couldn't find any more information on what that ratio is, just that it's different. Shimano has a whole line of high end (read, expensive) parts for the new 5800 drive set. The 5700 line was for 10 speed road bikes and has been around a long time and is compatible with a lot of different shifters and parts.

Maybe by the time I get all of my parts together I will have figured out what shifter I need to go with these parts. The biggest problem with the shifter is the 6.2mm pitch which is much bigger than the standard 5.5-5mm pitch, which is standard on most cogsets. I was looking at the 3 cog freewheel that I bought and it looks like I may be able to remove the cogs from the freewheel body. If that's the case, I would be able to mill down the spacers and change the pitch to the standard size, enabling me to use a standard index shifter. As soon as my new cog chain tool arrives from Amazon I will try to disassemble the 3 cog and get a better idea of my options.

Share this post

Link to post
Share on other sites

After buying my parts, it occurred to me that the one derailleur/shifter combination that might work, right out of the box, is an sram rear derailleur and a shimano left 3 speed shifter. The shimano 3 speed shifter pulls 6.75mm and the pitch on the 3 cog freewheel is 6.2mm so that might be close enough to work. The trick is to find a cheap sram derailleur. Sram derailleurs tend to be a lot more spendy than shimano. Also, sram derailleurs have a mechanism designed to work with a bit of slop in the chain/cog lineup.That combination might just do the trick. If someone out there has a shimano 3 speed front derailleur shifter that can actually measure the pull length, that would help alot. So far I'm just relying on data from the web.

I purchased the Shimano 105 because I wanted to have a derailleur that shifts really easy and from what I understand about shimano derailleurs is, the more you spend, the easier and smother they shift. My plan is to install an arduino tiny connected to a small stepper motor and driver circuit (as small as I can find, possibly from a printer with maybe a small gear head on it) to control the pull on the shifter cable. I The whole package should fit inside a box the size of a cigarette pack and fit inside the battery box. Then I can use an electric 3 way toggle switch to shift the derailleur. The whole thing can run off of a 5v Lithium battery that is charged from the bike battery or possibly run directly from the battery through a small cheap dc-dc stepdown converter. I could easily program the arduino to pull or release exactly the amount of cable needed to shift the derailleur. As a mater of fact I can think of a number of different mechanisms that could pull enough cable to shift the derailleur including a solenoid, possibly a 12v electric lock mechanism from a car. I have an assortment of electromechanical items in my well stocked junk box in my shop. What I don't have is physical data on the force required to pull the cable on the derailleur. This is actually what shimano and sram have done with their high end road bike shifters, but who wants to spend a couple of hundred bucks for a simple 3 speed shifter. Besides, they are proprietary and can't be easily programmed by the user. An arduino can be programmed by anyone using a computer and a usb cable.

As soon as my parts arrive I will be able to measure the force required to shift the derailleur and then I can decide which method to use, electronic or electromechanical. Whichever method I use I will design a simple, reliable device to shift the derailleur (at least as simple as I can make) and I will see about making them available to any Sondors owners that want to make the upgrade. Due to the low cost of chinese electronic parts, the whole thing would probably cost about the same as a descent shifter. Also I really like the idea of using 1 toggle switch to shift. the center position would be the standard driving gear and flip it up and you have high gear and flip it down and you have low gear. As a mater of fact, the more I think of this concept, it would be easy, once you had the arduino controlled shifter, to create an automatic mode that automatically shifted into whatever gear you needed by monitoring the current draw on the motor. Anyway, all of that is for a future post which I will start when this idea rattles around in my head a bit and my parts arrive so I can get some real data and work on the specifics.

By the way, I don't know if I mentioned it but I used to be a mechanical engineer before I became a computer nerd. Whatever happens, I will make my project available to the community either as a DIY project with instructions and a parts list or a finished plug and play device. Maybe I might even start my own kickstarter campaign and sell a complete 3 speed conversion kit. I imagine that there is a pretty good market for for an easy to install, finished kit. I'll post more details soon. 

Share this post

Link to post
Share on other sites

My goal originally was to make the parts list and instructions available so people could do it on their own. I like the idea of having a kit that we could sell and then help people get the conversion done and be confident in it working great.

Maybe we do a good internationally friendly shopping list of parts, then assemble a best of parts kit to sell. If its priced right, I bet a lot of people would buy it. I mean, once you get past all the "learning what works and what doesn't" - the conversion is pretty easy. You could even go as far as pre-tuning the derailleur so it's mostly good to go, etc.

All I have left on mine is to find a better shifter and to get the more permanent chain links to bond the 2 chains and its done.

Share this post

Link to post
Share on other sites

3-speed 2.0

Okay - I’ve now completed my second 3 speed conversion, and as guys my age like to say: “With experience comes wisdom.” Or, to be more honest, once you’ve screwed up one way, you need to work harder to figure out a new way to screw up.

I don't know if this has been covered in this thread because I can't access anything but page 6.

The biggest problem I had with 3-speed 1.0 was getting the existing single gear freewheel off. It screws on the usual way - “righty-tighty.” And since that’s the direction you pull on it every time you pedal, it’s on there but good. Worse, it lacks any notches or splines to attach a tool to to unscrew it. It “freewheels” in the “lefty-loosey” direction, so you can’t just grab it and twist it off.

Some pioneers in this endeavor (including me) tried putting a screwdriver or chisel in one of the two dimples on the face of the freewheel, and hit it with a hammer in the leftward direction to try to get it off. Eventually, that worked - after pounding it with a hammer and chisel for hours, destroying the part by sheer maniacal fury. After pounding off all the exterior parts of the device, what’s left can be gripped with a pipe wrench and twisted off.

Not an elegant solution.

It turns out there’s a less violent way to get it done. (Oooooh... a secret!) Turns out the little dimples on the front serve a purpose after all. If you put a screwdriver in one of them, and tap on it in a clockwise direction it unscrews. That’s right - it’s threaded on the freewheel with a backwards thread - righty-loosey. No real pounding required; a few confident taps and it starts turning. A minute or so, and you’re in. When you unscrew the cover, all the guts fall right out, with teeny little ball bearings skittering hither and yon, unless you thought to put a plastic bag over it while you were at the last step, in which case only a few cling to the magnets in the motor and eventually skitter.

Once you’ve taken those parts off what’s left has lots of grooves and bumps, and is no problem to grab with a pipe wrench and remove. The three gear freewheel spins right on. It does require two 12mm washers on the axle to fit tightly into the frame, but then you’re home free.

Of course, I needed a larger chainring on the front. I did that part two different ways. For the yellow bike, I found a four-spoked chainring with a flat spot where I could drill holes and bolt it right to the existing 40t Sondors chainring. For the white bike, I got a kit with a 48t chainring attached to a crank. That required getting a crank puller tool from my LBS for about $15.  The black chainring is a 3/32" (as is the 3-speed freewheel) and I used 3/32" chain on the yellow bike.  The white chainring was 1/8 so I cannabalized the two 1/8" chains from the Sondors' for the white bike.

So we’ve got two 3 speed bikes now. One has a Shimano shifter, the other is Suntour - both low-level shifters. Shifting to a higher gear is easy; bang, bang, bang.  Getting into a lower gear can take some doing, because the 3-speed freewheel doesn’t have any ramps on the side of the gears to help the chain up and over the larger sprocket.  But I haven't had a lot of trouble getting the 5-speed index shifter to work - I've got a SRAM left hand twist shifter for the Shimano derailleur and a right hand "Velo shift" twist shifter for the Suntour.  Both settle in just fine on three gears.  With the Suntour I use 1, 2 and 3; with the Shimano I use gears 2, 3 and 4 but I have to twist past 2 to about 1 1/2 to get the downshift into low to bite, before backing off into the 2 spot.   I’ve taken to downshifting before coming to a stop so I can start out in low; quickly shifting up as I accelerate.

2 bikes.jpg

white chainring.jpg

white chainring.jpg

Share this post

Link to post
Share on other sites

@Steve Condie - Glad youve made 2 work, each one we do proves it can be done and we refine the process.

Since you cant see past Page 6 ( @Andi?) I also figured out how to unscrew the freewheels without the removal tool slots. I used a set of rare earth magnets to try and catch the bearings and still went everywhere.

When I got the last 2 freewheels, I got ones with a tool to remove them and the tool itself, just in case.

Sounds like your experience was similar to mine overall, minus all of my cussing and buying and returning parts and doing and undoing things repeatedly. I've officially killed 2 1 cog freewheels, 2 3 cog freewheels, 1 crankset and returned 1 crankset, bent a chain, cut apart 2 chains, replaced 4 cable housings, cut and replaced 5 shifter cables, and broken 2 shifters.

But I can do it now in a few hours with the right parts. :D Looks good, let us know how the two derailleurs work once you've ridden them a bit. I am thinking of going with a lower profile one myself. it sticks down a lot and I'd like to bring it up closer if the shifts still work.

Share this post

Link to post
Share on other sites
1 hour ago, Steve Condie said:

I can't access pages 1 through 5.  I think I've seen 1 through 4, but not 5. 

8 minutes ago, alienmeatsack said:

I meant the previous pages, sorry. I have workers in my house and I've not had my meds and I am spacy lol :D

@Steve Condie @alienmeatsackYou should see now the previous pages again. Sorry, a Content Delivery Network gone offline, this affected to this topic. 


Share this post

Link to post
Share on other sites

@3D-vice - No changing the front gearing is not mandantory. However. your gear ratio will change across the board if you dont.

Since it comes with a 40 up front and 16 in back, that means with the new 3 speed, you are now 40/16, 40/19 and 40/22. Which means the smallest rear cog is now the matching gear and the other two become higher speed gears instead of getting a lower speed hill gear (or two) which for me was the point of the conversion. So starts and hills are still going to be just as tough, but you'd be able to go 25+ mph pedaling alone.

I went with 48 up front to equal the same gear ratio in the middle gear, giving me a hill gear, a stock gear and a faster gear. It's not totally perfect as it ends up:

Standard stock, 40/16 = 2.5

New gearing, 48/16 = 3, 48/19 = 2.53, 48/22 = 2.18

But its close. And at this point it's much easier to change out the front gearing to find the sweet spot then it is the back.

I know some went 46 or 52, the latter makes the 22 cog gear close to stock and the other two are hill gears. Its all a matter of preference and need.

Share this post

Link to post
Share on other sites

@alienmeatsack, you've got that backwards.  Larger cogs on the back = lower gearing.  If you don't change to a larger front chainring you'll end up with one gear at standard ratio (40:16) and then two lower gears.   And a larger front chainring makes for higher gearing, not lower.  52t gives you one ~standard and two "overdrive" gears.  It's counter-intuitive, I know, but if you look at your gears while riding you'll see what I mean.  With a 48t front the 19t middle gear is "standard" and you have one higher (the 16t cog) and one lower (the 22t one.)

Share this post

Link to post
Share on other sites

Like everything on this build, I struggled with the decision about what size chainwheel to use. I really wanted to use a 50t but had trouble finding one that was affordable and well built. I really wanted a chain guard for safety reasons and didn't mind adding one afterwards but I wasn't overly impressed with the available cranksets at the price point I could afford. I'm upping 2 bikes so I need to keep the cost down but I also would like reasonably quality parts. The crankset I bought was a bargain at $35 and includes a guard. If I decide that the 52t chainring is too large, I can always put a smaller one on for not too much money. When I get my CNC mill up and running this summer, I can always make my own chain rings Also, I still haven't given up on possibly making the front chainwheel a double by adding a second sprocket. I need to finish one bike first so I can get as feel for what I would like to do to the second bike. I don't live in a very hilly neighborhood where most of my local riding will take place so I really like the overdrive capabilities of the 3 speed.

After I get my parts installed I will be able to evaluate the whole drivetrain and then I will see about mounting an E type front derailleur and adding a 40t second chainwheel. I will probably add a 48-50t chainwheel to the second bike. My girlie is just a little thing and doesn't have the advantage of my long legs. That makes good low and high gearing a must for comfortable riding. I need to make sure that I tune both bikes to similar capabilities so she or I aren't peddling our ass off trying to keep up with the other.

Creating a master list of installed components (with links) will go a long way towards making this conversion an easy weekend project. The biggest problem we have all had is we are each, essentially, reinventing the wheel with the common thread being that we all have the same end vision of what that wheel should look like, just not how it goes together with our different parts. I know that we all have slightly different criteria as to build quality but I think our goals are very similar and the end costs should be reasonably close. With a good parts list we could stipulate a range of compatible parts of ,different quality, with the same specs allowing anyone to successfully finish their upgrade, spending as little or as much as their budget will accommodate. I personally have shopped so many components that I am damn near a walking encyclopedia of component prices and vendors. Now I just need to do the final assembly and figure out if my vision works.

One last important thing I need to check out is if it is possible to disassemble the cogs from the 3 cog freewheel. Most 5-8s have a 5mm or  5.5mm pitch on the rear cogset. Our 6.2mm pitch is the reason everyone is having trouble getting a smooth up-down shifting experience. After closely examining the freewheel, I still cant see if it's possible to remove the cogs but it looks promising. As I said, it would be a piece of cake to adjust the shim thickness between the cogs, making the cogwheel compatible with any standard derailleur. I should recieve my new cogwheel chain wrench soon and then I can retire to my shop and open a can of whipass on the cogwheel and force it to reveal it's secrets.

Not having owned any bicycles previously, leaves me woefully lacking in any spare parts to cannibalize, otherwise I would just take an old chain and make my own cogwheel wrench. A friend of mine, who just took delivery of his new Sondors bike (I assembled it for him), has several bikes that he found abandoned in the alley behind his house. It seems that he lives on the border of the snatch and ride neighborhood and his alley is a great parking spot. Maybe I'll visit him tonight and see what goodies can be found. These are generally older bikes of dubious quality but you never know, I might find some usable parts. I'll do a writeup, with pictures, when I have more information. In the meantime I am still working on my electro-mechanical shift mechanism and am currently shopping up parts on the web.

Share this post

Link to post
Share on other sites

So, just to keep this thread alive. I'm interested in doing a 3-speed conversion to my aluminum Sondors. But, I want to have a right hand 3 speed shifter with gear indicators. Plus, I'm still cornfused on the chainring/chain/freewheel pitch choices.

So, as I understand it....

I believe the stock Sondors has a black prowheel (pro-E44P looking) crankset, 39T chainring, 16T freewheel, and KMC Rustbuster Z410RB 112 link 1/2" x 1/8" chain

With those gears, according  to http://www.bikecalc.com/gear_ratios gives you 2.4 gear ratio.  The chain ring might be 40T, so that would give you a gear ratio of 2.5.

So, if I want to just add more hill climbing ability, I need to drop the gear ratio, which means I could...

  1. Keep the stock Sondors chainring, add some KMC Z410 links to the stock Sondors chain, add a Shimano FT35 short cage derailleur, and then add this Amazon 3-speed freewheel, this eBay 3-speed freewheel (for 1/2x3/32 chain), or this eBay 3-speed freewheel.
  2. Replace the chain/chainring/freewheel with a known pitch, but then have to worry about the chain guard issues.

So, my questions are...

  • Which freewheel matches the stock chainring and chain? All of them?
  • What right hand shifter would work best?
  • What right hand 3 speed shifter with gear indicators would work best?

Share this post

Link to post
Share on other sites

IMG_4677.jpgOkay, just finished my Aluminum Frame Sondors 3-speed conversion using the following parts list...

Using the following tools, that I already had.

  • Allen wrenches that came with the Sondors e-bike (for brake adjustment, handle bar grip, throttle, brake lever, and shifter)
  • Hammer & Awl (for removing the freewheel cover and breaking the bike chain) (Or buy a chain breaker)
  • 3/8 to 1/2 inch socket wrench socket (for breaking the bike chain) or you can use a piece of wood with a hole drilled into it. (Or buy a chain breaker)
  • Pipe wrench (for removing the freewheel mount)
  • 18mm wrench (for removing and installing the wheel)
  • 10mm wrench (for removing and installing the chain tensioner on the rear wheel)
  • Metal saw with fine blade (for cutting handle bar grip and shifter cable sheath)
  • Diagonal pliers, snips, or dikes (for trimming the zip-ties)
  • Phillips head screwdriver (for adjusting the derailleur)

Total cost was under $45.00 in parts. Using the valuable instructions on this thread. (THANKS GUYS!!!), I did the following steps in under 2 hours...

  • Put the Shifter on the right handle bar


  1. Using an allen wrench, loosen the two bolts in the metal brackets on the right handle bar grip. 
  2. Then pull the right handle bar grip off the handle bars, clamp it in a vise, and using a fine tooth metal saw, saw about 2 inches off (8 columns of nubs)
  3. Using an allen wrench, loosen the mounts for the throttle and the brake lever and slide them BOTH off the handlebar
  4. Put the thottle back on, then the brake lever, then the shifter, then the rest of the right handle bar grip.
  5. Make sure the cable runs are okay, and then using an allen wrench tighten all of the mounting screws down.
  • Replace the freewheel
  1. Put a towel/mat down to put the upside down bike on. (Don't mar the frame/handlebars/buttons)
  2. Unplug the motor plug that runs along the bottom of the rear frame.
  3. Take off both protective boots.
  4. Photograph BEFORE nut/washer/tensioner/frame/spacer/wheel pictures on both sides of the rear wheel. (It's a good habit, when doing projects)
  5. Using an allen wrench, release the tension of the rear brake wire.
  6. Using the 10mm wrench, release the chain tensioner bolt connector to the washer that runs to the back of the frame. 
  7. Using the 18mm wrench, remove the axle nuts and washers and chain tensioner on both sides.
  8. Take another picture of the orientation of the inner notched washer on both sides. (Trust me it's easier this way)
  9. Un-hook the chain and let hang on the frame, using a towel or cloth to prevent the chain from messing up the frame.
  10. Remove the rear wheel and place carefully with cable side UP.
  11. Using a hammer and awl, remove the old bike chain.
  12. Using a hammer and awl, tap the retaining ring for the single speed freewheel CLOCKWISE.
  13. Once the retaining ring is loose, remove the ring by hand, and then lift up the freewheel, catching the loose ball bearings with a magnet.
  14. Remove all the other rings, teeth, and then using a pipe wrench and hammer, tap the freewheel mount COUNTER-CLOCKWISE to loosen.
  15. Once the freewheel mount is spinning, remove it by hand.
  16. Put the 3-speed freewheel on by hand, and hand tighten (no need to crank it down, peddling will do this)
  17. Put both the extra 12mm washers onto the axle next to the new 3-speed flywheel.
  18. Put on both notched washers the same way as you took the pictures before.
  19. Put the wheel back on the bike.
  20. Using your fingers, put on the non-chainside nut/washer/tensioner and leave loose.
  • Mount the derailleur and adjust
  1. Put the derailleur onto the axle, adjusting the notched nut to be on the inside of the frame.
  2. Using the Phillips head screwdriver, tighten the screw holding the notched nut on the derailleur.
  3. Using your fingers, put on the nut/washer (LEAVE OFF THE TENSIONER!) on to the axle.
  4. Using the Phillips head screwdriver, adjust the H screw of the derailleur, so it sort of is in line with the smallest/outer gear. (we will fine tune later)
  5. Run the new bike chain through the derailleur, around the freewheel, and back over the crank, and clip in the master link. (or if you have a chain breaker use this to re attach the chain)
  6. Using the 18mm wrench and the 10mm wrench, tighten the bolts holding the wheel in place, and re-connect the rear brake. (You should be able to turn the crank and the wheel should turn. Now it's time to make the shifting work!)
  7. Take the shifter and using the 10mm wrench, un-do the nut on the cable end connector and remove the bracket.
  8. Pull about 16-18 inches of the inner cable wire through to the shifter handle section, take off the little black nub on the end of the cable sheath, and trim about 6 inches off the cable sheath with the metal saw.
  9. Put the black nub back on the end of the cable sheath and thread the inner cable wire back through the cable sheath.
  10. Run the shifter cable along the frame and down to the derailleur, don't zip tie it yet.
  11. Thread the wire end of the shifter cable through the derailleur cable mount, threading the holes and guides to the bracket.
  12. Make sure your shifter is turned to 1 (the lowest gear)
  13. Using the 10mm wrench, loosen the bracket nut, thread the shifter wire through the gap, making sure the shifter wire is tight and all the cable sheaths are mounted well, and then tighten the bracket nut.
  14. Turn the crank and shift through the gears, making sure that 1 is the small gear and 3 is the biggest gear. (If not then adjust in next step)
  15. Using the Phillips head screwdriver, adjust the derailleur so it doesn't jump the chain off the gears and shifts smoothly.
  16. Zip tie down the shifter cable against the frame and use the Diagonal pliers, snips, or dikes to cleanly trim the zip-ties.


  • Take it for a test spin!
  1. Using the Phillips head screwdriver, more finely tune the derailleur. (if needed)

You're done!

Enjoy your new hill climbing ability!


PS> Other tweaks that I've done to my bike...

  1. InterLock hidden inside the seat post bicycle lock - $50.99
  2. 25 Amp controller upgrade - $59.98 with free 15-25 day shipping (from China)
  3. LCD Control panel - $48.98 with free 15-25 day shipping (from China)
  4. 20W LED headlight - $39.99 with free 15-25 day shipping (from China)
Edited by Scott C. Kennedy
Spelling/ Grammar errors
  • Like 9

Share this post

Link to post
Share on other sites
5 hours ago, Tabletteer said:

Wonderful job on the conversion and documentation...superb. I can hardly wait for further ride results and especially how well the shifter works with the cogs.

With the new gearing I can climb a 20-25% grade for at least 150 ft before I have to stand up and pedal really hard.

Share this post

Link to post
Share on other sites

Thanks for the update. I can tell from your profile picture that vertical is very prominent in your environs. 

Our frames are too small for me. I was 6'1" in my younger years but probably 5'11" now. My torso is slightly longer than normal for my leg length so I've always ridden 56-57cm bikes with long Stems. Of all my rides, the Sondors is the most uncomfortable to pedal standing. It has the longest 3T CF 110mm stem I could find and 3T CF riser bars with very little sweep. I figger Storm sized this geometry for himself. <]:~) Got my 3-Cog today. I just replaced the chain that had stretched to limits but since it's pretty flat here, lower gearing is not my first priority. In stock configuration, spinning past limits has my legs moving like a Kitchen Aid Stand mixer at 25.5 mph. I might be able to maintain that for a hundred feet but I usually give up as I reach that escape velocity. On the pedals, I feel like I'm way over the bar. I looked for a 3T CF set back seat post but I couldn't find one at Aliexpress at all and none in the US for a reasonable price. I'm thinking a 52 chainring will give me a slightly lower and two higher. I'll wait for more ride results from board members before deciding. Again, thanks for your excellent info. I've created a PDF of your post and saved it to Evernotes. 

Share this post

Link to post
Share on other sites

I found another sprocket with 14-17-20 teeth (On eBay) but it is made for a 1/2 - 3/32 chain. I like the gearing better. Would I need to change the chain and or front sprocket too? Or could I use a 1/2 - 1/8 chain? TIA

Share this post

Link to post
Share on other sites

Like this one? http://www.ebay.com/itm/Mountain-Bike-Bicycle-Thread-On-Screw-Thread-Freewheel-14-17-20T-3-speeds-N2-/252135242006

Well, the chain size (1/2 x 1/8) or (1/2 x 3/32) means the links are 1/2 long and 1/8 or 3/32 wide, depending on the gears you have. So, it should work.

So in theory, you could use a freewheel like it, providing it has the right threading to fit the stock Sondors threads. vs. a splined wheel.

There are several different thread standards, so be careful!

Edited by Scott C. Kennedy

Share this post

Link to post
Share on other sites


Thanks for taking the time to share your upgrade knowledge here with us.

The three speed conversion is something I'd like to tackle after I get my bike

Your bike looks great!

Share this post

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Similar Content

    • By Roy Temper
      Motor Wires and Derailleur Protection
      Protect your motor wires going through the rear axel and if you have a derailleur with a derailleur guard. One of the best I have found is available at REI and is highly effective and provides a great deal more protection than the cheep thin guards sold online. Certainly worth the $20 i paid and if you have an REI near you it's available in most stores or at: REI.com

    • By Brandnew
      Just Ordered Fold X, LCD Screen question?
      I am Gary from Lagrange Ga. I just ordered a Fold X for myself and one for my wife, both with the 7 speed option. The info on the site shows the LCD screen and states 5 gears and 5 levels of assist.  Referring to the LCD screen it states "this option supplies Fold “X” with five gears and five levels of electric pedal assist plus added torque for increased hill-climbing power, even greater range, and improved towing capacity."  I understand the levels of assist but what would the 5 gears be that would be controlled from the LCD display? Does the LCD screen show miles or speed on the original bikes?
    • By 3D-vice
      Know your Gear - Freewheel vs Cassette
      Hey all,
      on my quest to gain more knowledge about bike parts, I stumbled over this nice video:
      Freewheel vs Cassette - What Are They? Can I Convert?
      As a noob, I found this especially helpful, since I'm about to exchange my original rear wheel with a new one. If those with professional knowledge out there have things to add, please feel free to do so.
    • By CrazySondorsRider
      Hello everyone. I've been a lurker here for a while and learned a lot from this forum. Well here's the situation, I got into a small accident last week and ended up bending one of the crank arms. It ran fine just up until tonight when I was riding home from the beach. My bike will no longer freewheel.  For a while if I pedaled enough the bike wouldn't freewheel but after about 2 minutes it would start to freewheel again. I'm at a loss at what I should do, my roommate fixes bikes for a living on the weekends at a local flea market and he says he doesn't have the tools to remove the cog that is on the bike. I have the fat tire Sondors bike from indigogo.
    • By MisterFixIt1952
      I have been working on a  3-Speed Conversion with alienmeatsack, biknut and steve-condie . I have 2 yellow bikes purchased on the third day of the first indigogo campaign, one for myself and one for my lady. I have purchased most of the needed parts. Three speed freewheel cog set, the derailleur and a new 52t sprocket crankset. The only part missing, besides a chain and some misc. hardware, is a shifter. Due to the odd pitch (pitch is the measurement between cogs) of the 3 speed cogset (6.2mm vrs. 5mm-5.5mm found on most 6-10 speed bike cassettes) I am unable to find a suitable index shifter that will work with a shimano derailleur. Apparently, no one makes an index shifter for a 3 speed, only a friction shifter or a twist grip shifter. I would really like to use an index shifter with a gear indicator. Not so much for myself, but to simplify shifting for my ladies bike. She likes things obvious and simple. Myself, I would use whatever I could cludge together, if I had too. With only three speeds it just strikes me that you should just be able to thumb the shift lever and shift up or down with the indicator showing 1, 2 or 3. Yeah, right!! We all know what should be and what is are often miles apart. No one makes a 3 speed rear derailleur shifter, they only make 3 speed front derailleur shifters and the two are entirely different animals with different pull lengths (the length of cable pull required to move the chain to the next cog).
      To solve my problem I have decided to investigate building an electronic derailleur controlled by an up-down shift switch. Now this might seem like a complicated solution to the shifter problem but being a mechanical engineer (in a former life) I decided to investigate the possibility. Shimano and Sram both make electronic shifters but at a cost of close to $2,000 for the set, I decided to see what good old DIY ingenuity could accomplish. Never dismiss the capabilities of a broke man with an expensive dream. Necessity truely is the mother of invention. Besides, it sounded like a fun project and being retired, I'm supposed to have time for fun projects, right?
      So, I did what any modern inventor would do, I went to Google for information regarding electronic derailleurs. To my delight, I found quite a bit of information on the subject. It seems that when shimano came out with their $2000 electronic shifter/derailleur setup, for road bikes, it set off a storm of shifter envy among the poor but inventive DIY community. The best website, devoted to the subject of servo shifted derailleurs, was DIYshift.com by Preston Fall (a fellow Oregonian). This site is referred to in almost all of the web articles that I came across. Unfortunately, the site is no longer available having been replaced by what ap[pears to be an Asian porno site. What makes this so unfortunate is the fact that most of the newer articles used DIYshift.com as a model for their designs and they refer to that site for pictures and details leaving little, useful, detailed information, just vague descriptions of the actual mechanism. Also, there are half a dozen uTube videos about DIY shifter projects. As is usual with uTube videos, there is a noticeable lack of hard information about how to build one with builders showing very little detail and few closeups, preferring to tease you with their cleverness and leaving you to fend for yourself figuring out the details.
      The good news is I found the contents of DIyshift.com on Github https://github.com/Diyshift (thank you Google)
      Here is a list of all of the uTube videos devoted to electronic shifters. https://www.youtube.com/results?search_query=DIY+electronic+derailleur This is worth checking out so you can see what the possabilities are.
      I also found an instructable detailing how to build an electronic derailleur. http://www.instructables.com/id/DIY-Electronic-Derailleur/
      This project is totally awesome. Not only does it solve the shifter problem but it can easily be upgraded to a larger cassette by changing the programming. Also, I have some ideas to turn this into an auto shift by putting a strain gauge on the crank chain that will automatically upshift or down shift depending on how much force I am putting into peddling. Much better than the cadence system built into the controller. It would be easy to also put together a shifter that would also shift a front derailleur by using a 2 channel servo controller. Do to the cheap cost of servo controller boards, DC-DC converters and arduino processor boards, this project could be put together for about $50 plus the cost of the derailleur. The whole system could be powered by the bike battery or a separate 7.4v Li-On battery, like the kind used in RC models. According to what I've read, a 7.4v battery is good for about 40,000 shifts (a conservative estimate).
       I plan on putting some real effort into this project, including designing a circuit board, shift switch with an led readout showing the gear selected and the servo mount. The software has already been written but I will check it out and make sure that it works with my version and is easy to use. I have an idea that will allow me to program the controller wirelessly using my tablet or a smart phone making it easy to tune the system. I think I will see about putting together a complete shift kit with everything but the servo and the derailleur. I have quite a bit of work to do on this but I will post more information as it comes. I am shopping up parts right now and still waiting for my shimano 105 derailleur to arrive. I'll know more when it gets here.
      Let me know if anyone out there that has any experience with one of these electronic shifters or if there is anyone else interested in this project.
  • Popular Now

  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use and Privacy Policy.