still plagued by annoying, crackling sounds produced by your Strida’s rear hinge?
It was a long and stony path, but I mean we are done now.
As Mark Sanders was so kind to help us massively, I felt free to order a considerable amount of TriLock nuts at an Austrian, professional CNC manufactory. The nuts were finished by another local plant which is specialised in anodizing, I’ve completed the kits with hardware from Germany and a bit 3D printed packaging.
With great pleasure, I’ll offer these kits from now on, starting at 17 € each, without shipping.
The nuts are in black or silver colour available, just mail me if someone is interested.
Dealer’s requests are of course also highly appreciated.
Required tools:
Allen key 2 mm
Allen key 4 mm
Ring key 22 mm
Kit content:
1 TriLock nut (anodized aluminium)
1 Allen set screw M 8 x 25 mm (stainless steel)
3 Allen set screws M 4 x 8 mm (stainless steel)
1 Cup spring (stainless steel)
1 Igus W300 thrust washer (plastic)
(Please open images in new tab to see them uncropped.)
When installing the TriLock, I tightened it with a torque of 23 Nm (according to my Strida EVO manual, the tightening torque for this point is 34 to 38 Nm), and the M8 set screw broke.
This was somewhat caused by me, prior to this tightening, I tightened the M4 set screw with a torque of 3 Nm, which crushed one of the screw heads and I had to remove that screw with an extractor.
As a result, the center M8 screw hole was slightly distorted and the M8 set screw was somewhat stuck when inserted into this hole.
Perhaps this is why the screw broke, but the guaranteed tightening torque for an M8 stainless steel screw from one Japanese screw manufacturer I checked is 7 to 12 Nm. (I am Japanese).
So it seems that TriLock’s M8 set screws must be tightened with much lower torque than the tightening torque listed in the Strida manual, but how much torque do yous use?
I have known about the existence of this forum since I purchased Strida, but due to the language barrier, I have not actively checked it, so I had no idea that the tightening torque listed in Strida’s manual was incorrect
(This was something I had never heard of in the small Japanese-speaking world. I would like to search this forum for your posts on torque to find out)
I am very shocked to learn that my Strida EVO was assembled overtorque from the time it was assembled at the bike store.
When I installed the TriLock, I had read the TriLock instructions, but I did not know how much to tighten the TriLock nut, and I was worried that it might loosen, so I referred to the tightening torque in the Strida manual.
Next time I would like to adjust by feel as you suggest.
Incidentally, u-84.hatenablog.com/entry/2022/05/11/192545
this is a blog post of one Japanese Strida user who describes how his TriLock M4 set screws started to loosen while driving. He applied Threadlock to the M4 set screws after this.
Because of this blog post, the tendency to apply more torque than necessary when installing TriLock has developed in me.
This is also troubling, because if a threadlocker is used, the next time the TriLock is removed, it must be warmed up with a heat gun before removal or it will break the screws.
I am very happy with your offer! but after purchasing a TriLock from Bikegang and breaking it, I hurriedly ordered two TriLocks already from Strida Canada West.
Well, It may take some time for those to arrive.
I do understand you very well; about ten years ago I attended the Hong Kong Strida forum. It is really hard if you have to translate each single post via Google; translating Asian languages will often show cryptical results, as you might know.
Back then, we were happy to have here at the forum „Amuro Lee“ (Hong Kong) and „GenuineS“ (Japan) - but since they left, the bridges to the Eastern communities are broken – I think this is a great loss for both parties – and I’m very sad about that.
Let me add this important details; maybe you could spread the word? The three worst mistakes in the recent Strida manual:
Torques too high, page 19
Method for belt tensioning wrong (without hook key doesn’t work), page 24
Amount of belt tension given wrong (not possible to reproduce, there is data missing), p 24
It is not the bikestore’s fault; they would (in best case!) check the bolts – but with wrong data from Ming cycle. I’ve unboxed several Strida bikes and I can tell – the rear hinge is already damaged when you take it out of the box for the very first time.
Please do a web search for the following: STRIDA manual-0617 revised.pdf
Perhaps you can find it still online somewhere…look at the torque page, compare to the actual manual, and be surprised.
You know, it is not possible to share attachments via our ancient forum mail.
Therefore, I suggest again to mail me in private (as below) and please let’s discuss the installation.
Regarding the torque at the TriLock I’ll try to explain the problem’s core:
The correct amount of tension at the cup spring is unknown; Ming cycle themselves doesn’t know and, so far, nobody was able to calculate the right amount.
But however, this unknown force works in the opposite direction than that of the applied torque at the nut – I hope that sounds logical.
So, if we do not know the upwards force – it is impossible to tell which force you need downward, right?
Many thanks for sharing this; it means a lot for me.
Yes we know; this happens if the TriLock nut was tightened too much!
I bet, in this case, the cup spring was totally flat (no more spring compression possible), that means that the friction (between frame/washer/cup spring/underside of nut) will increase massively. Friction will increase that much that each folding attempt loosens the nut.
This will happen with all systems, not only TriLock.
(And why does that not happen on the original joint?
Simply due to the sharp and thin edge of the original spring, instead of generating much friction it will cut into the tube surface )
The solution for the problem of your fellow countryman is; accept lower „damping“ and don’t overtighten the TriLock nut.
Well, first it should be mentioned that TriLock is intended to be used totally without threadlocker/lubricant. Mark Sanders choosed the IGUS thrust washers exactly for this reason, they don’t require grease, respectively they’re self-lubricating. https://www.igus.co.jp/search?q=WTM-1630-015%20
And regarding threadlocker in general; you did know that these products are colour-coded?
Please note that you’re talking above about the „RED“ quality – High strength.
You must not use „RED“ on Strida bikes!
Please use „BLUE“ – Middle strength – only.
(If you do. Anyway not for TriLock.)
I see. I am not spreading the word about Strida, but I would like to give it some thought.
I searched for that PDF and compared it to the original manual and am amazed.
I am tempted to replace the rear wheel axle.
I have seen pictures of a broken joint connecting the bottom tube to the front tube. Should I loosen this joint immediately as well?
And I found a terrible mistake between the English and Japanese versions of the Strida manual.
Well, according to you, the original figures are wrong. github.com/sumibi-yakitori/stri … ida-manual
Thanks for your fairly detailed explanation of TriLock. I studied a bit of mechanical engineering back in the day, so I was able to understand some of your explanation.
I will be careful not to over-tighten the cup spring.
I did not know that IGUS also had a Japanese branch.
According to the Strida manual, ritelok TL70 (3M TL71) is used. shandhigson.co.uk/3m-adhesi … -tl70.html
This is supposed to be Loctite’s “RED” equivalent.
Well, I have already lost a lot of faith in the Strida manual, but is the manual’s description of the threadlocker also wrong?
The fluid on the original M8 steel bolt is blue, so perhaps the manual is wrong.
I bought a TL71 and checked the color of its fluid it was red.
It is on me to say thank you very much for your interesting questions and your effort!
First; regarding your fellow countryman, can you get in touch with him?
Maybe we can help him together?
Are you in sorrow about the M8 thread?
The steel axle is 12 mm in diameter, as long as the thread was not ripped, it will be fine, I mean.
No!
Definitely not, because these broken “ears” (next to part 216) were caused by too loose 274 bolts!
This is a critical point at the Strida frame; both bolts have to be tight always and secured with (BLUE) threadlocker. And there is no need to fix them with with XXX Nm
(More on this below.)
Inattention of the finest…yeah, that is Ming…
Well…I wrote “given wrong”, to illustrate what I meant I’ll choose first a dumb example:
Imagine you would ask me for my weight, alright?
If I’d reply:“375000”
What would you think?
The unit is missing!
(I’ve used Carat.)
Similar with the belt’s tension, just to describe this, there are explicitly TWO units (or dimensions) required!
The applied weight (= dimension 1) will generate a certain deflection (= dimension 2) of the belt.
In other words - a mass of X kg (lbs, pound, carat, whatever) will bend the belt for Y cm (inch) downward.
That’s what I meant with “given wrong” - one half of the required information is missing.
And so, the info is as useful as that:
“This vehicle runs 400km/_ fast.”
That is very good, a bit mechanical knowledge will assist you perfectly to understand the following regarding Ming’s torque chart:
I mean we have clearly visible evidence that there’s something wrong at the rear hinge bolt!
It is an M8 bolt and on the head there is stamped “8.8” - this number is the strength class.
Now, if we look at torque charts, we can find a recommended maximum torque of 20 - 22 Nm.
Ming cycle wants this bolt to be tightened with 34 - 38 Nm.
Definitely no.
Regarding the two 274 bolts, left and right of 216, I have the suspect the situation is the same - but no evidence (there’s no stamping on these).
Hilarious, that made my day!
I have to confess that I never before checked this product, possibly it is not so common here.
But it is really “high strength” - which is anyway wrong.
Anecdote from today; I called my local folding bike dealer (actually an experienced engineer) and asked him about his use of RED quality threadlocker at his workstore.
Surprisingly he said “Yes, I do use RED”…and moved on:
“But at one single bolt (!!!) of the Brompton’s rear hinges exclusively - because it is strongly advised by the manufacturer.”
If his email address was publicly available on his blog, I would be able to contact him, but it is not.
The only way to contact him would probably be to send a mention to his Twitter account.
But I don’t have a Twitter account for private purposes.
If I can invite him to this thread (I think he knows about Strida Forum), I may be able to help in Japanese.
I see. I am relieved
Thanks. It is very helpful. I will take care about the loose bolts there.
Ahhh…
It really brought back a few memories of learning about belt tension in the past as well. I’ve forgotten most of those since I don’t do any work on mechanical engineering, but looking it up again, I see that it does indeed require a two-dimensional unit of measure.
When I broke the TriLock, I checked the bolt tightening torque table, and the torque table did indeed mention strength classifications.
I assumed that bolts of a higher strength grade (e.g., 12.9) would be required to withstand the tightening torques in the manual.
However, I was surprised to find that the bolts actually used were of strength grade 8.8.
In installing this TriLock, I bought a threadlocker for the first time. I think that even in our country normal people rarely use them.
I also have a heat gun, so even if it fails, I can manage. I don’t have a chance to use the high strength TL70 (TL71) anymore though
The Brompton example is interesting. Maybe they are using RED to avoid maintenance failures by average users.
First of all, I apologize to yakitori.
I am sorry for writing an article with wrong content.
I will respond with a corrective article in the near future.
After reading Blackstridaaustria’s posts so far, I found that I have not been able to install TriLock correctly.
However, so far my STRiDA rear hinge is comfortable with no loosening and no noise.
The Loctite used on the M4 bolt is the lowest strength purple, so I think it would come off if I wanted to.
Of course, I found out that that is the wrong way to install it, but since I am not in any particular trouble with the current situation, I would like to keep it that way for a while.
I think you may have translated it as “このブログ記事のせいで”, but “このブログ記事を見たことで” is the sentence I was thinking of in the original text.
I don’t think I failed because of you at all.
Rather, I am grateful to you for writing a blog post about your experience with TriLock.
I think my mistake was a good one because I realized that I was ignorant about the guaranteed torque for tightening screws.
And I am fortunate to have gotten to know Chris and u_84 because I broke the TriLock screw.
(I was going to write this message in Japanese, but I decided to write it in English because it would be annoying to Chris and others if I continued the conversation in Japanese)
Whatever the language, the information is much appreciated.
The content of the Strida Forum has helped me many times.
I also read with great interest the contents of this issue on TriLock.
Hello yakitori-san
So that’s what you meant.
That’s exactly what I had misunderstood.
Thank you for your kind words.
I am glad you read it too.
)
