Jump to content

Pedal stripped crank arm threads


Ridge
 Share

Recommended Posts

@Ridge

The only logical fix is to replace the Crank Set. Helicoils could replace the threads but it would be an unreliable fix for the stress it would be under. Be sure and check the threads on the Pedal Axel and run a die down them or replace the pedals too. You can buy Sondors Parts and pay a premium or you'll find aftermarket parts in the 3 speed and 7 speed upgrade threads on this forum. Since you didn't specify what model Sondors you own it's impossible to direct you to the correct replacment. But this fits the Thin, Sondors X & Original Fat.

https://sondors.com/collections/parts-store/products/crank-right

image.jpeg.68fbf91a4d8f54be54116723cd51c0f3.jpeg

image.jpeg.b8bec3ed6d409c68a55f5c983611290d.jpeg

Reddy

Edited by Reddy Kilowatt
Link to comment
Share on other sites

This type of failure is almost impossible to happen when the pedals are installed properly. Usually it's because they were either over tightened, or under tightened and came loose. It's worth the money to buy a special pedal installing tool. 

 

After new pedals are installed, it's a good idea to check them for looseness after about a hundred miles.

Link to comment
Share on other sites

The Square taper cranksets are cheaper than the Park Tools or service to repair the inexpensive cranks used on our Sondors. That would make sense on my Lightspeed Ultimate with the 25th Anniversary Dura Ace Groupo where the crank replacment cost is several hundred dollars. The cost of the Park Taps are $22.79 and $29.29 in individual sets. The Park 15mm Pedal wrench is $15.00 alone (any 15mm narrow, open end wrench is what works on our Sondors) and there's no reason to look up the cost of the Bushings...you can buy the whole Park Tool/UNIOR PEDAL TAP AND BUSHING SET for $129 from JensonUSA      http://www.jensonusa.com/Unior-Pedal-Tap-and-Bushing-Set

Any bicycle online supply vendor can sell you a quality Crankset for next to nothing.

image.jpeg.b8bec3ed6d409c68a55f5c983611290d.jpeg

Reddy

Edited by Reddy Kilowatt
Link to comment
Share on other sites

  • 3 weeks later...

There are opinions out there that point to shallow threads on the Sondors crankarms.  This leads to some of the reported failures.  The fact that there are people 'building' bikes who have no experience doing so is also a problem as pedals apparently are a bit of a tough nut to crack for some people.  The fact that one pedal is 'rightie loosie' (reverse threaded) has caused more than a few freakouts documented online.

To install pedals properly, you first coat the threads in anti-seize (white lithium grease is a decent second-best).  Just blob a little on your fingertip and roll that fingertip over the pedal threads which will wipe the goop off your finger and into the threads.  Next, thread the pedals onto the crankarm with your hands.  NOT a wrench.  There is plenty of room to just hold the things on and get them threaded in.  If you keep trying and the thing does not thread on, try going the other direction (this will solve about half the problems with threading pedals on).

When the pedals begin threading on, switch to any 15mm wrench.  A thin Park pedal wrench is nice to have but not essential as any Craftsman or noname open-ended wrench will fit - just barely - and clear these big boxy pedals.  Use two fingers to turn the wrench.  Thanks to the grease almost no pressure should be needed to turn the wrench on the pedals.  If you need to apply pressure, STOP and very carefully look to ensure you are not doing the other thing that accounts for most mistakes: cross-threading.  After your gentle tightening bottoms the threads of the pedal against the crankarm, just give a slight skootch of pressure...  Just a nudge.... to seat the pedal to the crankarm.  DO NOT make it any tighter than this.  Pedals are threaded so they cannot come loose over time from the rotation of the cranks.

Do this and a) the pedals will stay on, b) they will not loosen and c) they will easily come off if you decide to upgrade your cranks, or pedals, some time in the future.

Edited by MattRobertson
Link to comment
Share on other sites

If a picture is worth a thousand words .....a video ....you do the math. 

PEDAL INSTALLATION AND REMOVAL

This article will discuss the correct procedure for installing and removing bike pedals.

Getting Started

What Tools do I need?

It is often necessary to remove pedals to pack a bike for shipment. It is also sometimes necessary to remove the pedals for replacement and to service the pedal bearings. It is important to remember that pedal threads are different from left side and right side. The right side pedal has a right-hand thread (removes counterclockwise, installs clockwise). The left side pedal has a left-hand thread (removes clockwise, installs counterclockwise). Many pedals are stamped “L” and “R” for left and right. Additionally, the thread will appear to slope up toward its tightening direction. Left hand threads slope up to the left, while right hand threads slope up to the right, as seen below.

Left: left-hand threads on a left pedal. Right: right-hand threads on a right pedal.

3

Begin by identifying the right and left pedals. Look for “L” and “R” marking on axle or wrench flats. If no “L” and “R” marking are seen, use pedal thread direction to identify pedals. Left threaded pedals (threads sloping upward to the left) go to left crank. Right threaded pedals (threads sloping upward to the right) go to right crank. See image at top if in doubt.

  1. Heavily grease threads of both pedals.
  2. Using fingers on wrench flats, thread right side pedal into right crank. Use wrench to snug pedal.
  3. Position wrench on flats for good mechanical advantage. Hold wrench with one hand while holding opposite crank with other. (Pedal the bike backward to install both left and right.)
  4. Using opposite arm as second lever, tighten pedal. Repeat process for left pedal, but threading pedal counter-clockwise to install. Typical torque for pedal thread is about 360 inch-pounds. With a foot long wrench, that is about 30 pounds of effort.

If pedal is difficult to thread into arm, or if the threads in the crank are damaged, there may be some repair possible by chasing them with a tap. For 9/16” x 20 tpi pedals, use tap set TAP-6. For 1/2” x 20 tpi pedals, use tap set TAP-3. Taps will align damaged threads, but will not restore metal that is simply removed. If no threads are left, have a professional mechanic install a pedal bushing kit.

4

Pedals bearing may be serviceable depending upon the manufacturer and model of pedal. Some pedals use adjustable cup type ball bearing system, and may be cleaned, greased, and adjusted. Service tools are proprietary to each brand. Some pedal models are not intended to be serviced, and are simply ridden until the pedal wears out. Pedal bearing service is typically best left to professional mechanics.

 

Pedal bodies often are made with small screws and bolts. These screws hold together the cage and mounting plates. Occasionally check that these fasteners and the cleats on your riding shoes are tight. Additionally, lubricate the pivot points on clipless type pedal systems.

image.jpeg.b8bec3ed6d409c68a55f5c983611290d.jpeg

Reddy


Edited by Reddy Kilowatt
Link to comment
Share on other sites

  • 6 months later...

Any suggestions for a Fold X crankset? The battery isn't even through 2 bars of the original charge and the right pedal stripped out and fell out of the crank. The bike was professionally assembled by very reputable bike shop to make sure it was done right. They used anti-seize on the threads. I put a torque wrench on the left pedal and it clearly seemed to be in spec.  I checked at 310 (about min torque per park tools). It didn't move. Didn't move at 350 but finally turned a tiny bit at 375. So the left was torqued somewhere between 350-375 in/lbs.

How does Sondors handle the warranty? Is it even worth contacting them? I clearly don't want the same sub-par part to replace it.  So my thought is to just bite the bullet now, replace it with something better and be done with it. It fell apart a few minutes into my first "real ride". I made a few quick runs around the house dialing in the seat, bars, etc. So this was my first real shake down cruise of any distance. I was never standing on the pedals or out of the saddle.

I have to say I really love a lot of things about the bike. I am big folding bike fan and still have about 6 other folders in the garage from a Bike Friday to a Brompton. I can really see the appeal of people who want to tweak this platform. I don't really need any more performance but a few add-ons would be nice. So once I get the crank sorted out it is time to accessorize away. 

Link to comment
Share on other sites

Hello you Devil,

Go to the Sondors.com web site during US West Coast business hours and use the messaging button to connect to a real live  human with your quandary and request, then follow up with an email. That insures your in the queue but messaging will get you more immediate attention. 

Of course you  sound like a very experienced cyclist and you’ve purchased a great ebike with lots of potential and I’m sure you have experience sourcing parts for bikes. I also installed an aftermarket crankset as many of our other members have to personalize our Sondors.  You can review other Fold upgrades and owners options by using the search function on every page.

image.jpeg.460181aebee7ca43d0f0c2b7c7188c24.jpeg

    Reddy

Link to comment
Share on other sites

Thanks Reddy  but I had already searched the forum and didn't see anything specific to the fold X specifically and see what others have used. I went about 3 pages deep in the search results. It looks to be a square taper crank. I'll get rid of the crappy wellgo folding pedals while I am at it and likely go with quick release pedals instead when I make the swap.

Link to comment
Share on other sites

TD, I don’t remember anyone changing Cranksets  on a Fold but Origin 8 components have been popular products for several of us upgrading. 

Not sure what the tooth count is on the Fold but take a look here:

http://www.origin8.bike/product-description/?prod_model_uid=1006

http://www.origin8.bike/product-description/?prod_model_uid=9459

http://www.origin8.bike/product-description/?prod_model_uid=6339

image.jpeg.460181aebee7ca43d0f0c2b7c7188c24.jpeg

     Reddy

Link to comment
Share on other sites

When my pedal stripped the crank I believe the issue was the washer that was supplied with the pedal prevented enough thread depth.  I watch the assembly video and it showed to use the washer in the pedal assemble.  On all the bikes I have assembled before that I never been asked to put a washer on the pedal.   Sondors took care of me  and when I got the new crank I put the pedal on without the supplied washers and have not had an issue.   Without the washer the thread depth of the pedal was much greater.

Hope this helps.

Reddy Edit: There are no washers supplied for Pedals with any model of Sondors nor with any replacement Sondors Pedals.

REDDY

Link to comment
Share on other sites

350 in lbs (about 29 ft lbs) is still too much pressure to put on those threads.  For crankarms that are forged and use top quality alloy, its not a problem.   As I posted above, use gentle hand pressure with a tightening tug at the end of the process to cinch to the crankarm.  Nothing more.  This works well for both high quality and base quality hardware.   Pedals will not come loose on their own if done this way, but crankarms ALWAYS will and need regular re-torqueing to  ~ 35 ft lbs.

These and similar 'entry-level' cast alloy arms are infamous for stripping pedals out.   A hub motor'd ebike does not need a robust drivetrain since primary power comes thru the axle and bypasses the drivetrain... so this is an area where oftentimes a production ebike gets parts that would never survive on an analog bike.

@Tasmanian Devil your problem is on a bike new enough - it sounds - that Sondors would likely warranty the failure.  Get on their web site and chat with them about it.  They'll probably replace them.  Frankly that would not be my first choice I  would take the time and minimal expense and replace the crankset with something that will accept a variety of chainrings so I could do some experimentation.

Link to comment
Share on other sites

Thanks for the feedback Matt. I plan to swap them out with something else ASAP and not even both with the warranty. 

To that point, anyone know the crank size on the Fold or Fold X? I am away from home on business for a week and forgot to measure it before I left. I'd like to get a better crank ordered and install when I get home later.

Link to comment
Share on other sites

Well, crank size is not going to be much of an issue... You can go either 165mm or 170mm.  You'll be buying just JIS/square taper crankarms and bolting them onto the bottom bracket spindle.  I have an inquiry over on the Facebook support group asking other Fold owners what they replaced with and hope for a link to some nice ones shortly.  The only real question I have is if you need something with a wide Q factor or not.  Its preferable on the full size fatties but not essential.  I think considering the tires are 4.0's on the Fold you should be good with whatever floats your boat... but likely 165 arms will be the best choice.

Link to comment
Share on other sites

Hah I got a quick answer.  

https://www.amazon.com/dp/B00C1C7PU8?ref=yo_pop_ma_swf&th=1&psc=1

These are known to fit Sondors Fold and Fold X.  However for a Fold X you are going to want to put on a chainring that works for 7-speed.  The one accompanying this set is for singlespeed so it'll be sticky.  Will be easy to do as they are 130 BCD so 44T+ rings will be easy to find.  And with the colors available you have a good shot at a color match.

EDIT:  These work great on my fattie but... I'm single-speed, so again you'll want a chainring for gears.  They are more expensive but workhorses.  Also nearly straight crankarms.   as narrow as you will get away with I am sure.  Mine are 175mm.  I doubt you want that length and 165 and 170mm arms are available.

http://a.co/24Oj9HG

Link to comment
Share on other sites

Thanks Matt. I was thinking about maybe going with something smaller, perhaps as small as a  160 or 155mm as well.  I don't need a lot of torque as I have very strong legs. So the smaller diameter would allow me to pedal faster a bit easier. A wider Q would be good for me in general. 

So the stock chain ring is a 44T?

Link to comment
Share on other sites

  • 1 year later...
On 9/24/2017 at 1:52 PM, Ridge said:

I just had my pedal strip the threads out of my right crank.  Has anyone else had this problem.  What is the recommended repair?  The threads are stripped and ruined in the cranks pedal 

 

On 9/24/2017 at 1:52 PM, Ridge said:

I just had my pedal strip the threads out of my right crank.  Has anyone else had this problem.  What is the recommended repair?  The threads are stripped and ruined in the cranks pedal threads.

The best thing for stripped pedals is pedal bushing inserts

Link to comment
Share on other sites

On 9/25/2017 at 6:43 AM, Reddy Kilowatt said:

@Ridge

The only logical fix is to replace the Crank Set. Helicoils could replace the threads but it would be an unreliable fix for the stress it would be under. Be sure and check the threads on the Pedal Axel and run a die down them or replace the pedals too. You can buy Sondors Parts and pay a premium or you'll find aftermarket parts in the 3 speed and 7 speed upgrade threads on this forum. Since you didn't specify what model Sondors you own it's impossible to direct you to the correct replacment. But this fits the Thin, Sondors X & Original Fat.

https://sondors.com/collections/parts-store/products/crank-right

image.jpeg.68fbf91a4d8f54be54116723cd51c0f3.jpeg

image.jpeg.b8bec3ed6d409c68a55f5c983611290d.jpeg

Reddy

Pedali per Bici 

When choosing bike pedals, first think about the type of riding youll be doing. Will you be road biking or mountain biking? Are you looking for the pedaling power and efficiency of clipless pedals (where cleats on the bottom of the shoes secure your feet to the pedals) or the ease and maneuverability you get with flat platform pedals? Perhaps you want the benefits of both.  

 

If you decide on clipless pedals, be sure your pedals, cleats, and shoes are made to work as a system. You can shop for either the shoes or pedals first, just keep shoe-pedal compatibility in mind as you decide. Cleats may be sold with the pedals or separately.

 

Why choose Sugelary pedals? Sugelary pedals provide a high level of control while riding fast or executing moves like hopping up onto curbs or over logs. Your feet wont bounce off the pedals as you apply power or while riding through the bumps. It can take some practice getting in and out of clipless pedals, but once you get the hang of it theyll feel like second nature.Pedali per Bici 

Link to comment
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.

Guest
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.

 Share

×
×
  • 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.