Also I didn't know about the integrated server. I have always been using the installed Dedicated. Where do I find the integrated server and what are it's benefits?
The integrated Server (i guess that is the one that you use already) is the one that can be found in the Folder
...\rFactor 2\Bin64
The other Option is the Steam Command dedicated Server.
I always would recommend to use the integrated Dedi, as long as you want to use it only for yourself.
The Benefit is, that you don't have to frickle around with Steam Command and you also don't have to install all Content, that you want to use on your Server, 2 times.
To your Problem:
As first, before you start the dedicated Server, set the Values
"Downstream Rated KBPS"
and
"Upstream Rated KBPS"
both to 5000, in the Multiplayer.JSON File, from the Player Profile that you use for the dedicated Server, which normally is your default Player Profile.
Check if that helps to get rid of the Lags.
If that doen't help, try to join the Server by a direct Connection Link.
Create a Shortcut of the "Launch rFactor.exe", that can be found in the Folder
..\rFactor 2\Launcher
then move that Shortcut to your Desktop for Example, rightclick on it and select Properties.
You will find something like the following Line in the Field "Target"
"G:\Steam\steamapps\common\rFactor 2\Launcher\Launch rFactor.exe"
where the Path to rFactor 2 probably will be different on your Machine.
Edit that Line with the Addition (
bold)
"G:\Steam\steamapps\common\rFactor 2\Launcher\Launch rFactor.exe"
+multiplayer +connect="127.0.0.1:64297"
HINT: between " and +multiplayer and between multiplayer and +connect has to be a white Space.
and if you use another Port than the default 64297, you have to adapt that.
Then save the Changes and doubleclick on that Shortcut when you want to join the Server.
Does that help?