[Hypnos]

If you have a different diameter tire then stock, or you have aftermarket gears, you will need one of these units to make your speedometer accurate again. You could also use one of these units to raise your limiter (if you have one), by throwing your speedometer a little off. Be aware that it will affect your handeling if you have a speed sensitive steering rack (a rack with wires going to it).

Abbot ERA - $140
http://www.abbott-tach.com/era.htm
Known to work.

Yellow Box - ?
http://www.blackrobotics.com/
No one has tried this one yet.

 

[JoeKD]

here's the yellow box pricing

Prices
1 Yellow Box = $100 USD + $10 airmail, total $110 USD
2 Yellow Boxes = 2x $96 USD (ea) + $10 airmail, total $202 USD
3 Yellow Boxes = 3x $92 USD (ea) + $15 airmail, total $291 USD

 

[Avenger]

OK, so who wants to buy yellow boxes besides me?

Speedo is reading 14% high