Speedometer accuracy

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Immigrant · Tue Aug 02, 2005 10:46 am

I am wondering how accurate the speedos are on bikes...i had heard/read that they are not very accurate, in fact , they are horribly inaccuarate...doesnt make sense, but...just wondering if there is any truth to it...

Forsaken · #2 Unread post by **Forsaken** » Tue Aug 02, 2005 10:54 am

We've got speed limit signs with radar guns under them and a big diplay that tells you how fast you are going. They pop up various places, I assume when enough people in an area complain about speeders. Last time I went past one of those my speedo was reading 3mph faster.

mydlyfkryzis · Tue Aug 02, 2005 11:02 am

I have a Etrex Legend GPS. My speedo is about 10% off. At an actual 55 MPH it reads 60 mph. At an actual 30 MPH, it reads about 33-34 MPH.

I don't mind as if I am doing the Speed limit as indicated on the speedo, I am safe from Speeding tickets. However, I am always about 10% over the limit (as shown on speedo) so I am usually just doing the real limit.

Forsaken · #4 Unread post by **Forsaken** » Tue Aug 02, 2005 1:25 pm

Doing the limit on the speedo doesn't excuse you from tickets. (At least here in PA) That's why you're allowed 6 miles over, for "equipment differences."

Aggroton · #5 Unread post by **Aggroton** » Tue Aug 02, 2005 1:30 pm

Forsaken wrote:Doing the limit on the speedo doesn't excuse you from tickets. (At least here in PA) That's why you're allowed 6 miles over, for "equipment differences."

yeah they usually give you around 11 mph wiggle room unless your from out of state....

#6 Unread post by **Sev** » Tue Aug 02, 2005 2:12 pm

Aggroton wrote:
Forsaken wrote:Doing the limit on the speedo doesn't excuse you from tickets. (At least here in PA) That's why you're allowed 6 miles over, for "equipment differences."

yeah they usually give you around 11 mph wiggle room unless your from out of state....

Tickets are payable now... in cash.

Loonette · #7 Unread post by **Loonette** » Tue Aug 02, 2005 3:09 pm

I've never actually checked the accuracy of my speedo, but I have heard that they typically can be 10% off in either direction. I don't worry too much. I usually go 10 over the limit in most areas. If I'm out in the country, I'll go 15 over.

A friend of mine is on our local police force - I think I'll ask him to radar me some day just to find out what type of reading he would get. He yearns to own a bike anyway, so maybe he'll be inspired when he sees me on my Meanie.

Cheers,
Loonette

#8 Unread post by **ZooTech** » Tue Aug 02, 2005 3:15 pm

Loonette wrote:maybe he'll be inspired when he sees me on my Meanie.

What guy wouldn't be inspired by a chick on a Meanie?!

Pogu · #9 Unread post by **Pogu** » Tue Aug 02, 2005 6:32 pm

Usualy about 10% off, or not off depending on the bike. If your realy worried about it, go to your local bike shop and pick up a Sigma Sport BC600 bicycle speedo or any model with a higher number. They are about the most accurate way to measure your speed, so long as you figure out your wheel diameter (it may be circumfrence, I forget.) correctly. I have a Cateye unit that starts again at 0 after 54mph, the Sigma Sport units are reputed to read wll of 100mph, at wich point you really shouldn't be looking at the guages.

Immigrant · Wed Aug 03, 2005 7:27 am

I see...i thought that there would be a some discrepency but didnt think it was horribly off...even cars are off a little...guess nothing to worry about...thanks!