The speed sneaks up

[Tom K.]

Originally Posted by Duckw

Checked speedo with GPS. Result substantially as using revs: off just over 2 mph at 60, 3 mph at 70. Indicated 80 is about 76.5.

Seems typical of recent BMW's - speedos usually read 2~5% high, although the instantaneous OBC speed is usually pretty accurate. Some have speculated that some European markets legally require that the speedo not read low, so there is a small fudge factor.
Tom

[esses]

http://ticketassassin.com/


Mandatory reading for CA 1 drivers. :thumbup:

[TunedM2C]

So were the car rags really doing 0-58 times? I'm sure they all had their own gear to accurately record data.

[confusion]

Originally Posted by Duckw

Checked speedo with GPS. Result substantially as using revs: off just over 2 mph at 60, 3 mph at 70. Indicated 80 is about 76.5.

That's almost identical to my results. I've tested my gps against 3 cars now and it's consistently read slower than my speedos have indicated. The gaps (as mentioned above) seem to be pretty consistent. Makes me wonder if it's my gps that's a hair off...

[robert.payne]

My '03 330i speedo reads 3mph higher than indicated on my gps while my '03 Z4 is dead on with the gps. Go figure.

[Duckw]

With my Porsche 996, the needle was about 5% optimistic, but the digital speedo, the one easier to see, was bang on. I'll have to try using the instantaneous reading on the OBC. Maybe we should use that instead of the needle?

[Duckw]

Whoa! The OBC readout for speed is only the average speed. It would be hard to use that to check the speedometer. Are there OBCs on other BMWs that show current speed? Or is there some way to trick the 135's OBC to read current speed?

[raisemyrent]

Originally Posted by robert

There is a built in speed warning feature, which chimes you to death, but it works.

is there really? that's neat... I may not have to go to court that often anymore...

[mikeo]

Our '07 Cooper S has a great digital speed readout that is realtime. I prefer it over the giant analog speedo in the center of the dash. Wish the 1'ner had that.

[bski]

Whats up with the bmw speedos. My 325 as well as my new 128 are both off by 2 mph. Confirmed by my GPS and overhead road speed monitors.
Speedo shows Im going 2 mph faster than acutal.
Maybe they do it for leasees. 2 mph over =200 miles extra on odometer for every 10k miles, thats probably 400-600 miles on the total lease period...pretty substancial I think. 500 extra miles on lease x an extra .10 = only $50 but x 5000 vehicles =$250,000 in extra revenue for BMW. Hummm
Cant believe BMW is unaware of this issue.

[IDBMW]

Cruse control is your friend, use it if traffic permits. It will save you tickets. Also, get a radar detector. My radar detector will go off and I will do a speed check to make sure I am not over the speed limit. It has saved me several times.
:w00t:

[BMW Dreamer]

Originally Posted by thesmokingone

SNEAKY

Mr Deeds. COOL :w00t:

[BMW Dreamer]

Originally Posted by IDBMW

Cruse control is your friend, use it if traffic permits. It will save you tickets. Also, get a radar detector. My radar detector will go off and I will do a speed check to make sure I am not over the speed limit. It has saved me several times.
:w00t:

DITTO. I use cruise control all the time. From 35mph and up. I WISH the 135i had the cruise control buttons on the steering wheel like the last 6 vehicles I have owned. The cruise control is like OLD SKOOL GM.

[BMW Dreamer]

Originally Posted by mikeo

Our '07 Cooper S has a great digital speed readout that is realtime. I prefer it over the giant analog speedo in the center of the dash. Wish the 1'ner had that.

My Civic Si also has a digital speedo thats high up and so easy to see. Its awesome.

[Tom K.]

Originally Posted by Duckw

Whoa! The OBC readout for speed is only the average speed. It would be hard to use that to check the speedometer. Are there OBCs on other BMWs that show current speed? Or is there some way to trick the 135's OBC to read current speed?

When the OBC is reset, it will read out the instantaneous speed at that time - so it's no great trick to quickly compare that to the speedo reading. After that, the readout is an average until the next reset.

Jeff, I've had BMW's with the cruise on the wheel and on a stalk. After becoming familiar with both, the stalk actually became more intuitive. What's more important to me is a visual dash icon indicating the CC status: off, on or engaged.
Tom

[IDBMW]

Originally Posted by mikeo

Our '07 Cooper S has a great digital speed readout that is realtime. I prefer it over the giant analog speedo in the center of the dash. Wish the 1'ner had that.

On the Z4 there is a way to get the speed readout where the odometer is. You do it by holding down the trip meter and/or clock adjustment buttons, it then goes into some mode where you can select the speed readout. You have to know exactly what you are doing or you will change some other settings since it is not user friendly. I Wonder if the 1 series has this function. On the Z4 it was not in the manual, I read it on the Z4 message forum.
:iono:

[Duckw]

[QUOTE=Tom K.;121706]When the OBC is reset, it will read out the instantaneous speed at that time - so it's no great trick to quickly compare that to the speedo reading. After that, the readout is an average until the next reset.

Thanks, Tom K. Having doped out just this same discovery on a trip this morning, I was about to post this solution. That readout is so close to the speedo. though, that I suspect they may both be using the same data. And there seems to be an absolute correspondence as well between the speedo reading and the number that comes up when you first select the Cruise Control or change its speed. I suspect that the GPS and rev methods that expose a slight optimism in speedometer readings are a more reliable index. It's of course also possible to clock mile posts with the cruise control set at exactly 60, that being the easiest to calculate. Any speed would do, though, with a good chronograph and create a pretext to use the tachymetric scale, a furbelow on chronos that most wearers never use. No end of options for the compulsive, I guess.

[Tom K.]

[quote=Duckw;122004 No end of options for the compulsive, I guess.[/quote]
Exactly. A few years back, I read of at least one BMW dealer who offered to physically bend the speedo needle so his pampered customer wouldn't have to read a gauge with a 5% error.

The worst speedo I ever encountered was on a '76 BMW motorcycle. I ran it up to it's honest top speed of 102 (checked by the tach) and the speedometer read 125!
Tom

[Dan203]

Originally Posted by bski

Speedo shows Im going 2 mph faster than acutal.
Maybe they do it for leasees. 2 mph over =200 miles extra on odometer for every 10k miles, thats probably 400-600 miles on the total lease period...pretty substancial I think. 500 extra miles on lease x an extra .10 = only $50 but x 5000 vehicles =$250,000 in extra revenue for BMW. Hummm
Cant believe BMW is unaware of this issue.

I don't believe the odometer and speedometer are linked like that. In fact I'm pretty sure there are strict laws to help protect consumers from odometer fraud. So if something like this were going on BMW would be in a whole lot of trouble with the US government as well as looking at a major class action suit from owners.

Actually I think the speedo being a little slow is a good thing. It'll make it so if I set the cruise control to 80mph I'll show up on radar at 78 in which case I'm a lot less likely to get pulled over. (there are a few 70MPH highways around here) And if I'm going 90 then I'll show up as only going 88, in which case the ticket will be a little cheaper.

Dan

[mistermojorizin]

Originally Posted by Jeff1962

My Civic Si also has a digital speedo thats high up and so easy to see. Its awesome.

my 01 vette had a head up display that reflected off the windshield like a little hologram. amazing, never had to take your eyes off the road. the 1 could desperately use that option, the way i have my seat and wheel adjusted, i can't read the speed and rpms off the gages. oh well, that was 7 years ago and that was gm, i'm sure bmw will eventually catch up (yea i know its an option on some cars, still, bs that its not an option on the 1er).

[mistermojorizin]

this weekend i was following a friend in a late model civic and my speedo was saying about 55mph. I asked her later, how fast she was driving and she said exactly 50 b/c that was the speedlimit. I know, totally unscientific and her speedo could read low, but if its true, 10% is a significant difference.

[bimmer98]

when you turn on the cruise, the dash shows the speed set. mine pretty much conforms with the GPS testers. below 50, it seems spot on. at 60, it's a few off, at 80, about 3.