Has anyone had problems with the JITSIE chain tensioner spring (Parts reference JI820-13321N Chain guide spring Race TRS 16-25)

[Elmadriles]

The problem I've encountered is that the spring is not the same size as the original, it has longer pins and a different angle and it doesn't fit into the tensioner arm anchor. I've sent them an email with photos and they tell me they've never had that problem since it's a clone. ALSO THEY SAY IT'S STAINLESS STEEL AND IT'S NOT BECAUSE IT'S MAGNETIC AND STAINLESS STEEL IS NOT. (There are some stainless steel ones that have a slight amount of iron and are slightly magnetic but this isn't the case since iron is very attracted to iron.

(I have the emails sent and their responses, as well as a video showing the spring's magnetism that I can't upload.
Can you tell me how to upload videos?)

Email Jitsie muelle ingles.pdf

[Elmadriles]

Email Jitsie muelle ingles.pdf

[lemur]

Yep, I bought one of those too, it's not bent correctly, ended up sourcing a package of regular assorted coil springs from a hardware store and improvising something that works as good or better to the original.

[faussy]

All types of SS are predominantly iron. You argue it's not stainless because it's magnetic? I would expect a ss spring to be magnetic, because the very act of cold drawing and then tempering makes stainless magnetic...

Edited August 14 by faussy

[lemur]

If we want to get all scientific there a 4 types of stainless steel and it is the chromium content that largely alters the magnetic attraction of the steel and the possibility of nickel added which has a grain that does not make a good magnet, all steel contains iron.

The problem with the replacement spring in question is, they bent it in the wrong place.

[anachronism]

4 hours ago, lemur said:

If we want to get all scientific there a 4 types of stainless steel and it is the chromium content that largely alters the magnetic attraction of the steel and the possibility of nickel added which has a grain that does not make a good magnet, all steel contains iron.

The problem with the replacement spring in question is, they bent it in the wrong place.

What year is your bike? I purchased two of the Jitsie springs in 2020, they fit my 2018 perfect after snapping two of the useless stockers (03012TR100) in 75 & then 25 hours.

Looking at my 2025 right now, it looks like the TRS spring has an extra coil compared to the Jitsie. I assumed TRS was just purchasing the springs direct from Jitsie but looks like they are sourcing their own imitation. The 2025 is a second generation swing arm, maybe TRS monkeyed the hole/pin location for their new spring compared to first generation?

[lemur]

I have a 2021 and a 2023 the replacement spring was difficult to install and broke within a very short time, then I went for the extension type spring as a more reliable alternative and I can source them at a hardware store, so I figure why not just set it up for that type of spring.  If there is no spring the bike does not roll backwards and the tensioner arm binds up.

[Elmadriles]

I emailed Jitsie, and they responded that they hadn't had any problems with those springs. They asked me what year the bike was, and in the end, they brushed it aside, saying the spring wasn't suitable for my bike's year.
I'm an amateur mechanic, and what I really enjoy is engine tuning. Back in the 1980s, I'd already tuned Vespa engines for racing, Puch Minicross engines with adapted Derbi cylinders, Puch Cobras manufacturing 6-stroke transfer cylinders... I have books from mechanical engineers on 2-stroke engine tuning, and also some MS-2 software for calculating reed valves, transfer case openings, and RPM, as well as calculations to determine carburetor diameters and some exhaust pipes, among others. What I mean by this is that I consider myself to have a minimum of mechanical knowledge, and I believe I know how to calculate BHP or RPM of an engine using mathematical formulas. I think that when I get a spring that they say is a clone of the original and it turns out the measurements don't match, I think I know how to perform the analysis and measurements to determine if it's good or not. You just have to look at the photos where it's clearly evident that they are not the same.
I ordered the spring from a prestigious specialty store (they sponsor a private pilot in the World Championship), and they told me they didn't sell that spring because it didn't work. They sold the original. That's why I decided to order it directly from Jitsie.
What I mean by this is that I don't like being treated like an idiot, and that my intention at all times is to give them information about the product they're selling, and that it's not what they say it is.

[Elmadriles]

[Elmadriles]

Can't you put videos?