Speedo adjusting?

[sunhuntin]

I hope you told him to jam it up his bum.

i wanted to, but i was a bit beyond speechless. lol. i dont do well in such situations. i think he was in a foul mood before i got there though. he couldnt get me on having been drinking [one rule i imposed and always follow], so accused me of speeding when he had no cameras or lasers to back up his claims.
how many of us remember what speed we are meant to be doing once we are past the sign? he asked what speed the sign said, but i couldnt remember as i had adjusted my speed to what was asked and then forgotten what id read as the info was no longer needed.

[dogsnbikes]

ive been wondering about the accuracy of my speedo for a while, so tested it against a "your speed is" sign. i went past with my needle exactly on 50. the sign told me speed was 45! is it possible to have the speedo adjusted so its accurate? i tried upping my speed by 5, but it was impossible to keep it steady and watch the road at the same time.

cheers!!

call in sometime or PM me and we can compare your speedo with the bold'ors speedo as that has just been calibrated by robinson's instruments in STH Auckland.....
but 5kph at 50kph I wouldn't worry about spending a couple of hundy on as most of the time you will be going with the flow of the traffic in a 50k zone

lets see how much Variation there is at 100kph,then you can decide what you want too do with your speedo

[ready4whatever]

how accurate are those speed sensors? my ute does the same thing, although i have replaced the gearbox, never know what these mechanics do

[Cajun]

Note that bikes of European origin often have a deliberate 7% error built in. This is because in Europe manufacturers aren't allowed to make a speedo that tells you you are going faster than you actually are. So to fix this problem, they make them deliberately say you are going 7% faster than you really are.

Very noticable in BMW cars as well ... If you have a GPS then it is really obvious.

Hmmm i think you a bit incorrect

I have a speedohealer on my gsx-r, which i have measured with a gps, at 100km/h its with in 0.5kms,


I have then in turn compared my bike with our Italian RSV-R, and what you know at 50km/h same speed, and at 100km/h both read the same also. Which shows its is not out. The rsvr goes off rear wheel revolotions, so changing sprockets, tire sizes etc does not throw it out, since its taken off the bolts that hold the rear brake disc to the rim, unlike japanese bikes which take it from the front sprocket



I did this due to fact i have changed the sprockets which throws out speedo, and suzukis on average are 8% out (before i correct it)

[Goblin]

There's a permanent electronic warning sign just south of Pirongia on SH39, on the way to Otorohanga. It's set up just before an interesting set of S bends...so far I have never gone through it without it saying "SLOW DOWN". But I have never managed to get it to say "YOU FOOL!!!!!" yet...

Maybe cos you're not breaking the "two second rule".

[slofox]

Maybe cos you're not breaking the "two second rule".

Ahhh..mmmm could be!!! Din't think of that!

[Disco Dan]

ive been wondering about the accuracy of my speedo for a while, so tested it against a "your speed is" sign. i went past with my needle exactly on 50. the sign told me speed was 45! is it possible to have the speedo adjusted so its accurate? i tried upping my speed by 5, but it was impossible to keep it steady and watch the road at the same time.

cheers!!

Your speedo should have a number printed on the face (more likely the older it is). Usually 3 digits long and gives the drive gear - revolutions per mile/kilometer. If this is wrong which could be the case with different front tire size, wheel size etc then it would be possible to change the gear drive from the front wheel to read more accurately. This number will most likely be printed behind the speedo face on more modern speedos.

[Swoop]

I like to speed up so it tells me to "SLOW DOWN!"

The devices we have up here tell me I ride like a nana. It always says "NOW SLOW".

[CookMySock]

i wanted to, but i was a bit beyond speechless. lol. i dont do well in such situations.

What you need is practice, my dear. Try wandering around all day approaching family and perfect strangers alike - "Hey you! Jam it up your bum!"

In a week, you will be an expert, hehe.. Everyone will be wondering what the HELL has got into you.

Steve

[Max Preload]

I haven't had that experience with vehicles not from Europe.

For example, my Holden Commodore says exactly the same speed as my GPS reports.
I'm sure Ford XR6 and XR8's will be the same.

My 'coon is spot on at 100km/h according to my GPS.

[sunhuntin]

What you need is practice, my dear. Try wandering around all day approaching family and perfect strangers alike - "Hey you! Jam it up your bum!"

In a week, you will be an expert, hehe.. Everyone will be wondering what the HELL has got into you.

Steve

hell, i do that already. i nearly belted a guy at work cos they used my hose without asking and returned it with tape wrapped around it claiming it had a hole. didnt have a bloody hole last time i used it, the cock suckers. they wont be getting into my cupboard anymore cos my keys are coming home with me from now on.
would have told the cop to shove it, but i was shocked at being accused of speeding in the first place. plus i didnt want a ticket just cos i was giving back what he was dishing out.

dogs... cheers for that! will pm you for your addy when i know ive got some time spare. dont get very much of it anymore, lol.

disco... only numbers on my speedo are the speed ones [50, 100 etc] shes a 98, so im picking the number you mean is hidden. never thought about front wheel size making a difference, even though ive read about it on here. cheers for that.

[Disco Dan]

This will also help:

[TimeOut]

if its possible (i havent figured out how to do this without breaking shit) take off the speedo glass etc, and just replace the numbered backing with an accurate one. Record the major speeds with gps, and mark on glass/original backing to aid in calibrating the new one.

I got a corrected face plate from the States (in metric), looks exactly the same as the old one but the numbers are in the right place (have checked it with the GPS)

[Disco Dan]

I got a corrected face plate from the States (in metric), looks exactly the same as the old one but the numbers are in the right place (have checked it with the GPS)

Good thinking, however that method is flawed.

A gear spinning either at the wheel or sprocket spins the speedo gauge - now if that gear is wrong for the size of the wheels etc etc and is giving an incorrect reading then the inaccuracy would be progressive. Ie at 20k would say 21k at 50k would say 53k at 100k would say 112k etc etc

This would mean your gauge would have numbers not equally spaced in order to give accurate reading throughout the range.

Quite often an inaccurate gauge reading can be rectified simply by changing tire profile or in the case of a stock standard setup - a light oiling of cable and speedo assembly. More drastic measures (as I already stated) require a tooth count of the sender gear and replacement with correct tooth count of gear to give rev per k correctly to speedo.

[CookMySock]

Bah, just ride along at exactly 100km/hr on the GPS, and carefully pull the needle off the speedo and put it back on at the correct position. Easy!

Steve