DC 4127 sprag from AliExpress (2019)

This is the company I purchased from

https://tinyurl.com/y5ng97ps
Glen, the company you linked above no longer has the DC4127 (C3) sprag clutch in stock. Searching Ali Express, 2 other companies stock a sprag clutch by that part number [$22 -$28 US]. However, their sprags, as shown in photos, have 20 rollers [aka dogs], rather than 18. Perhaps this is a further design upgrade? What are the dimensions of the item you purchased?
 
It is an 18 roller/ tooth sprag.
I did measure it before installing to verify that it would go in. Unfortunately I did not make a permanent record of the dimensions.

Glen
 
It is an 18 roller/ tooth sprag.
I did measure it before installing to verify that it would go in. Unfortunately I did not make a permanent record of the dimensions.

Glen
Glen, was it the same size as the older 14 roller unit? I ask, because my Mk III project has the older 14 roller unit. It's still good, but I'd like to have a spare on hand, at a reasonable price.
 
Glen, the company you linked above no longer has the DC4127 (C3) sprag clutch in stock. Searching Ali Express, 2 other companies stock a sprag clutch by that part number [$22 -$28 US]. However, their sprags, as shown in photos, have 20 rollers [aka dogs], rather than 18. Perhaps this is a further design upgrade? What are the dimensions of the item you purchased?
OK, I just ordered 2 of the inexpensive sprag clutches. Turns out the photo is simply a generic photo. Price was $22 each, with free shipping. Buying more than one gave a 10% discount. Plus, when I logged in, I received a $3 coupon, good on any purchase till the end of this month on any order over $5. That reduced the total to $36.60. With the discounts I'm only paying $1.30 each more than you did in 2019. Hopefully, no issues ordering 2 with the free shipping. This vendor had the fastest shipping time of the three [20 -40 days] Time is not an issue here. I figure, if I'm lucky, I'll have the bike done by the end of the year. My original 14 dog bone sprag is still in good shape. Thank you for taking the time to post this info to the forum.

DC4127(C3) Sprag on AliExpress
 
The sprags are probably to size.
The original norton parts are what I found to be slightly inaccurate for this standard industrial item specifications. The correct inner and outer component dimensions are avaliable.
AN and STS have probably improved over the original OEM noton item tolerances.
I too, have never had a sprag problem with the 14 dogbone OEM items. I have a 2 new 18's on hand just in case. I personally believe the thin inner spring is an extremely important item to its engagement properties. If a few independent dog bones skid around they will damage an individual spring finger item . However I can't prove it...
 
The sprags are probably to size.
The original norton parts are what I found to be slightly inaccurate for this standard industrial item specifications. The correct inner and outer component dimensions are avaliable.
AN and STS have probably improved over the original OEM noton item tolerances.
I too, have never had a sprag problem with the 14 dogbone OEM items. I have a 2 new 18's on hand just in case. I personally believe the thin inner spring is an extremely important item to its engagement properties. If a few independent dog bones skid around they will damage an individual spring finger item . However I can't prove it...
I ordered in 3 cheap 18 roller sprags from Ali Express.
Then I blew the bank and ordered in the CNW upgrade.
It's a 14 roller with a stronger cage , with super hardened sprockets.
Have not tried it all assembled , yet , due to -10 Celcious tonight with a - 20 C. wind factor , so be it.
 
I ordered in 3 cheap 18 roller sprags from Ali Express.
Then I blew the bank and ordered in the CNW upgrade.
It's a 14 roller with a stronger cage , with super hardened sprockets.
Have not tried it all assembled , yet , due to -10 Celcious tonight with a - 20 C. wind factor , so be it.
Aww, quit yer cryin’. Set up your little tent, get your knee pads and get to work! Lol!
 
I ordered in 3 cheap 18 roller sprags from Ali Express.
Then I blew the bank and ordered in the CNW upgrade.
It's a 14 roller with a stronger cage , with super hardened sprockets.
Have not tried it all assembled , yet , due to -10 Celcious tonight with a - 20 C. wind factor , so be it.
Just get an old ice fishing shed...
 
6th one down
real DC 4127 sprag data

All these should be interchangeable.
If yours fails and you complain about the sprag, then NAME the manufacturer not the seller. Include the real condition of the inner and outer races or your complaint is meaningless.
 
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If you need on in a hurry: https://www.vxb.com/DC4127-Steel-Sprag-One-Way-41-275x57-935x13-5-p/kit18278.htm

The price has gone up since the last one I bought, installed with all new mating parts from AN and hasn't missed a beat since.
Having read Daves comments, I inspected the items I just received with a magnifying glass. I just visited the VXB link above. Using the large photo of VXBs sprag clutch, I note two similarities to the Chinese units I purchased. Neither has any markings indicating part number or manufacturer. Both show small inperfections in the contact surfaces of the individual "sprags". The seller on AliExpress mentions that a common use for this sprag clutch bearing is in automotive torque converters.
 
Correct, this is a "nothing special" industrial one way clutch though categorized with bearings. The ID and OD running surfaces are as important as the sprag. Very few folks have the myopic vision, as I unfortunately do, to examine the norton mating surfaces. I can see them "up close" LOL 1-2" from my nose and they are often not very good. but on their 3rd sprag.....?:eek:
 
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