Attak Speedo Accuracy

[nate007]

If you are goint to remove teeth on your speedo sensor, make sure if you do more than one, you remove one of them 180 degrees from the other. One tooth on each side of the gear, or you will not read accurately, but I've heard 2 teeth makes it dead on at high speeds. I don't have a radar gun, but I do have a Garmin 496, but it's too pricey to take sledding, I only use that in the airplane.
Nate

 

[ZR800EFI]

If you are goint to remove teeth on your speedo sensor, make sure if you do more than one, you remove one of them 180 degrees from the other. One tooth on each side of the gear, or you will not read accurately, but I've heard 2 teeth makes it dead on at high speeds. I don't have a radar gun, but I do have a Garmin 496, but it's too pricey to take sledding, I only use that in the airplane.
Nate

I only took off one tooth and at trails speeds it's pretty much bang on, which I prefer over top speed. At 100MPH GPS I'm now 107 speedo where before I was about 111 speedo.

Only reason you'd take two teeth off is to have top speed accurate.

 

[ROCKERDAN]

Guys...I rode an entire weekend with GPS mounted to pad....As ive said last season,2 teeth is EXACT.

Its EXACT at EVERY SPEED....I tested it all weekend,trails,lakes....i specifically tested it with my GPS at 10,20,30,40,50,60,70,80,90,100 MPH....and ALL were within .1mph....you cannot get it any closer then that....

I have also radared my sled at 120 in which the speedo with two teeth removed(opposite sides) read 120.

1 tooth is NOT accurate and IMO is like doing half the job....I really am not sure why anyone would take the time to remove gear,grind off one tooth,and not do the entire job.

this statement is False from ZR800EFI"Only reason you'd take two teeth off is to have top speed accurate"


2 teeth works.
Dan

 

[SledFreak]

Dan, what did you use to grind the teeth off?

 

[ROCKERDAN]

Dan, what did you use to grind the teeth off?

Dremel with small grind wheel....didnt take more then a few minutes each side...just put it into a vise and grind till tooth is flush to hub.

 

[ZR800EFI]

Dan, sorry. I haven't had my GPS mounted, but thought it was only more accurate at slower speeds with 1-tooth. Most posts are talking about top speed when grinding this gear, so I assumed that's what the second tooth was for. I'll take another tooth off then...not a big deal at all.

Sorry for the incorrect info...

 

[ROCKERDAN]

Dan, sorry. I haven't had my GPS mounted, but thought it was only more accurate at slower speeds with 1-tooth. Most posts are talking about top speed when grinding this gear, so I assumed that's what the second tooth was for. I'll take another tooth off then...not a big deal at all.

Sorry for the incorrect info...

LOL..no worries!...

I wanted to be sure I was correct,cause i had heard so many talk about 1 gear being correct at LOW speeds...so last weekend i mounted the GPS where i could read easily at all speeds to test thouroughly.

It is interesting how much closer 1 tooth makes it,while 2 teeth gets it perfect...kinda weird,I would think 1 tooth would be 7mph off still.

one thing I should add here,just so ALL ARE AWARE.....your ODO will now be LOW...many have said they are MORE concerned with ODO being accurate,so whatever you need more accurate be aware of that.

It is so interesting to KNOW that Yammie builds this into the sleds speedo...they must since ODO is correct and speedo is hi....they must just want to keep the 'watercooler' chatter to sound good for speeds.LOL.

Dan

 

[yamadoo]

Not to be bleeding blue but my polaris XCSP 8 reads very close to my APEX and my buddies older polaris's do also.

I think alot of our complaints come from the digital read out. I mean when it says 117 you are sure you saw that yet when my Poo is bouncing between 115 and 120 I am not so sure what I saw so I cut it more slack.

That being said, I wouldn't doubt that is was designed to be a little "happy" as they know perception is everything in marketing.

my two cents

Yamadoo

 

[ZR800EFI]

Dan, sorry. I haven't had my GPS mounted, but thought it was only more accurate at slower speeds with 1-tooth. Most posts are talking about top speed when grinding this gear, so I assumed that's what the second tooth was for. I'll take another tooth off then...not a big deal at all.

Sorry for the incorrect info...

LOL..no worries!...

I wanted to be sure I was correct,cause i had heard so many talk about 1 gear being correct at LOW speeds...so last weekend i mounted the GPS where i could read easily at all speeds to test thouroughly.

It is interesting how much closer 1 tooth makes it,while 2 teeth gets it perfect...kinda weird,I would think 1 tooth would be 7mph off still.

one thing I should add here,just so ALL ARE AWARE.....your ODO will now be LOW...many have said they are MORE concerned with ODO being accurate,so whatever you need more accurate be aware of that.

It is so interesting to KNOW that Yammie builds this into the sleds speedo...they must since ODO is correct and speedo is hi....they must just want to keep the 'watercooler' chatter to sound good for speeds.LOL.

Dan

Agreed on the ODO...only one tooth off and it's now pretty much identical to my GPS. My buddys RTX at 109 miles, my GPS and ODO read about 100 miles. Cutting teeth off really hurts the fuel mileage!!! :ORC Last year I went 150 miles without running out...doubt that can happen now!

 

[craze1cars]

My findings with stock speedo gear: 115 speedo = 100 gps...reconfirmed many times.

122 speedo = 105 gps (my highest speed to-date without really trying too hard)

Garmin Etrex Legend CX is my test GPS.

Never really checked the lower speeds, but mine is clearly reading about 15% higher than reality, and I believe that is all the way from zero to max. This would come pretty close to the 2 tooth trick,...as grinding 2 of the 15 teeth accounts for a 13.333% reduction in speedo pickup impulses.

I'll also note that my odometer reads about 2% higher than my GPS trip meter after a long day's ride, so it's pretty close.

 

[ZR800EFI]

After 152.7 miles yesterday on the GPS, my ODO said 152.1 with one tooth ground off. Just posting to see how others compare.

 

[Turk]

Local radar runs yesterday(1000') on a brutal track with no studs & 100% stock clutching. Speedo said 100 mph & gun said 83 mph. Buds 800 pt doo shortie with 1" track exact same speed. 05 mach Z with 1.4 track & geared down went 91 on the gun. F-7 sno pro hit 78.

 

[King44]

I think YAMAHA should be the first to use a GPS in their speedo.Forget about reading a spinning track.Imagine total accurate speed and odometer.

 

[King44]

I think YAMAHA should be the first to use a GPS in their speedo.Forget about reading a spinning track.Imagine total accurate speed and odometer.

 

[ROCKERDAN]

I think YAMAHA should be the first to use a GPS in their speedo.Forget about reading a spinning track.Imagine total accurate speed and odometer.

grind 2 teeth off...its as close as my GPS at every speed....sure spinning doesnt count but without spin and two teeth off its exact...Ive been running with GPS alot lately mounted to barpad...i compare the two all day long with my GEAR MOD..and they are exact.

dan