How far is speedo off.

[crazycam]

Hi, I just bought my busa 2 weeks ago. I have noticed that the speed seems to be off. when I was doing 80mph by my friends bike he was doing about 73/ 74 mph.

[crazycam]

Is eveyones like this or is it just mine ?

[ATC'er]

Sounds right (if your friends is showing true speed).  Mine was off by 8%, so 80 mph - 8% = 74 mph.

[crazycam]

Is there anyway to fix this ?

[ATC'er]

I purchased a product called "Speedohealer" from one of the site sponsors (STREETn TRACK IMPORT ACCESSORIES; they have a link in the PRO SHOPS section of this forum).  It plugs into the speedometer cable and sends a "corrected" signal to the dash speedometer.  It's quick and easy to install and works great.  There's also a top-speed recall button that will display the fastest you've gone.  When you hit the button, the speedometer needle swings to the max speed you hit, stays there for several seconds, then returns to zero (or current speed if you're not stopped).

[TrickTom1]

mine was off 8% too with stock gearing

[jrp0629]

Any idea where I can get a spedohealer and how much they are. I just started to notice the same thing, doing "80" and getting passed by everyone on the highway.

[newbusaguy]

Any idea where I can get a spedohealer and how much they are. I just started to notice the same thing, doing "80" and getting passed by everyone on the highway.

Street And Track Imports sells them!
Here is the link! It is about 1/2 way down the page!
http://www.netmemberservices.com/members/streetntrack/cart/inv.php?catid=6&start=20

[BATTMAN]

You can also use a yellowbox

[PetriK]

With stock rear tire we tested in dyno that when speedo was @ 300km/h (186mph) the bike was running around 264 (164mph)on the roller. That counts arond 12% so error seems to be progressive, there should have not been much slip on that run. Usually seen around 7% at around 100km/h (62mph) when compared to GPS measurements.

Speedohealer is quite good in correcting the error using the calculator they have wirtten. The biggest factor is rear tyre as first of all the diameter reduces when it gets wearn out and secondly as in high speeds different tyres seem to expand somewhat different amounts.

[piratediverjefff]

About 8% here also.

[BATTMAN]

What percentage would the speedo be off with 16/42 gearing?

[piratediverjefff]

What percentage would the speedo be off with 16/42 gearing?

Can't say myself since i've never run it,but when i was at 17/43 my speedo would read 80 mph and everybody on the freeway would still fly by me(probably 15% off or better).Switched to 18/43 now and like it a lot better for the road.

[BrutalBusa]

I use to run 15/40 gearing on my bike, that made the gearing (and the speedo) about 15 percent off stock. If you add the 7-8 percent the speedo is off from the factory you end up almost 25 percent off. The way i corrected mine was to remove the 4 metal shoulders on the pickup for the speedo sensor. I then made 3 new pins that are arranged in equal thirds around the pickup. That effectively reduces the speedo by about 30 percent. It's not a perfect fix, you are still about 3-4 percent off but it is very close...........100 mph on the speedo is about 95 mph in real speed. I checked it with my GPS and it worked out like the math said it should. It's a cheap and easy fix that doesn't require any additional space or wiires to run.

[woodykc]

Buy a GPS all bike speedo's are off.

[dkirk]

mine is off 5mph at low speeds, and upto 15mph at high speeds. Which is better a yellowbox, or speedohealer?