What are these markings for?
 

Fella's,
What are these little markings (red circled) for?

http://home.planet.nl/~ros00022/speed2.jpg


Thanks!

They show the maximum speeds for each gear so you know if it is safe to change down.

Thanks Mick, but I'm a little thick I guess. Can you explan a bit more?

Thanks

when you are travelling at a high speed, and you want to shift to a lower gear, you want to make sure you do so at a speed which would not have the engine above redline in the target lower gear.

for example, you are travelling at 120kph in 3rd or 4th gears, and you slow down for a corner, planning to downshift to 2nd gear. This means that you have to be below (about) 97kph to be able to safely downshift to 2nd gear (i.e., the "II" marking on your speedometer). Presumably, you will be braking for the turn, ready to downshift to 2nd, and you should wait until the car slows down to this speed before engaging 2nd gear.

for best results, you should be rev-matching, and if you can, heel-and-toe downshifting. This is for a manual transmission, of course.

I thought it was an up-shift point.

you could use them as guides for upshifting, but the tachometer is much easier to use.

for downshifting, however, it is much more difficult to use the tachometer - you need to know the relative ratios between gears to determine if a downshift now will exceed redline in the next gear, and you need to calculate this quickly ($$$!!!) ... The markings on the speedometer face make this much easier to figure out.

as an additional point, note that there is no marking for 4th or 5th gears (if the car has a 5th gear). This means that the car is drag-limited in these gears, and there is no way that you can (normally) exceed redline in them.

i have a 5spd 190e2.6, and there are markings only up to 3rd gear. This means that at any speed in 5th (even top speed), I know that I can safely downshift to 4th - just have to rev-match to be easy on the drivetrain and synchros. I have not driven the car this hard though ...

bobbyv,
Thanks for the explanation. It does puzzle me still, I mean, the revs are incredibly high when downshifting (& upshifting) at these marks. But I gues that's just my style of driving....

Thanks!