You can find the installer without a JRE here https://bamboo.igniterealtime.org/browse/SPARK-NIGHTLY-1451/artifact/shared/Install4j-generated-media/
Build number is higher, but this is just because new build is automatically produced each day. There are no changes in this build.
Btw, which version of Java are you using? 8 or newer? Do you run into any problems with that? Also, which vendor? Oracle or maybe Redhat or AdoptOpenJDK?
Ok, now I am a little confused. I don’t have Java installed on any of my Windows 10 machines here. I have always downloaded the EXE without JRE.
I can guarantee that Spark won’t run without Java. 
There’s probably something installed by default on your system.
Windows 10 must have something. I will have to look into this.
I installed all new Windows 10 PCs last year and did not install any Java, and I used the spark 2.8.3.exe.
The size IS bigger than the 2.9.0 ones, though.
I just bought a fresh machine last week as a spare. It’s bare except for Windows 10 (volume license copy so no bloatware) and I will go install the Spark without JRE and see if it works.
That installer of 2.8.3 you have is with JRE. Without it it would be around 40-50 MB. Spark is not installing Java to the system. It has it in its installation folder (C:\Program Files (x86)\Spark\jre). It is not visible to other apps and is only used by Spark. So, if you don’t install Java on your systems, you need the one with JRE included.
My mistake. I didn’t realize the one that didn’t say JRE actually does have it. That would explain why it works!
Before 2.9.0 build setup was different and version with JRE was just spark_2_8_3. The one without JRE was spark_2_8_3_online. Now it is somewhat inverted.
Ahh! Gotcha. That explains it.
So…I used the non-JRE 2.9.0 and 2.9.1 just recently. So I guess my JRE is using what was leftover from 2.8.3. Should I be installing the JRE one for future reference in case there are changes to the JRE?
Spark installer (or rather install4j, which is used as installer) leaves current jre folder during upgrade, if it doesn’t have newer one. 2.8.3 had 1.8.1_121. 2.9.0/2.9.1 comes with 1.8.1_202, which i think was released in January (last one with freeware license from Oracle). I don’t think there is anything major. I think there was one issue with incorrect time in some countries and 202 fixed that (daylight changes). So, i guess it is better to use newer one, if possible.
2.9.2 is now released.