The VW Golf GtI MK 2 cluster inside the car says on the bottem KM/H. But if I drive 100 km per hour the cluster says 60. So it is MPH inside the car cluster. Not the display of the in game screen.
And the Golf MK2 GTI did not have a top speed of 260 KM/H on the gage/cluster.
indeed , hope the next patch this week will solve the problem
I ve just check in forza horizon 5 : the same car has not the problem.
the cluster Gauge displays normally in kmh
I had the same issue. The issue was solved after I upgraded to:
Race exhaust
Race airfilter
Race intake
I upgraded the car with race exhaust , race airfilter and race intake , but the issue persists for me 
I m sorry…… i forgot to mention the race ignition, sport oil cooling.
Also 205 mm tire on the front and rear,
rims “KÖNIG AFTERBURNER”.
I don’t know wich part is the solution.
I hope it worked for you to.
oki , thank you very much for information , I ll try to add thess improvements tonight ;)^
edit : arf , in fact I tested immediately : so I add race ignition , sport oil cooling , 205 mm tire (front and rear) , rims “KÖNIG AFTERBURNER”
and unfortunately same problem , gauge is in mph instead of kmh on this car
It’s also overheating, has a backlit dash cluster when it should be front lit, and the model is as old as the hills. 
I own 4 Mk2s, always saddened me they did it such a disservice.
still bug despite update
hope it will be solved in mext patch
still not fixed despite update
Also came across this bug a couple days ago, have a screenshot of it
Cluster reads “100 km/h” while the HUD displays 100 mph
Hoping it gets fixed soon as well 
indeed , but this problem happens since the release and unfortunately , still not fixed.
All cars with speedometer bug (or rpm gauge bug like Golf 8R) still not fixed
This is what happens when a FM1 model is reused.
arf I m really afraid they ll never fix this kind of bug
In FM7 , they never fixed some bugs like that.
But I dont understand , I think it s really easy to fix and unfortunately they don’t patch the game often.
They could release a small patch every weeks to fix minor bug.
Hi, I’m currently racing against the 1997 McLaren GT, when it brakes the front indicators come on as brake lights. Then the Pagani Huayra has a gray haze/pixel under the steering wheel when you look through the clasp. Then finally fix the unclean graphics in the game. And please finally take the sounds from Horizon in Motorsport - what else I noticed, I wanted to paint the original rims of the 2016 Porsche 911 GT3 RS black matt, the paint becomes dark gray almost original color. Please fix it!!!
Still bud despite update 4.0 
I ve just seen the changelog : they solve livery issue on some cars but not a speedometer issue
still bug despite update 5.0
still bug despite update 6.0 , so disapointed
@StarfoxManiac @DutchRacer1968 Do the two of you have the same system?
doesn’t know about the system of DutchRace1968 , I have a PC (win 11 , RTX 3080 , 5800x , 32 Gb etc… )
I tried to upgrade Race exhaust , Race airfilter and Race intake but still issue for me
