I've gone down a tooth on my front sprocket, but now my speedo seems like it's miles off. I've not got a frame of reference, but I expected it to over-read by 2-3mph, it feels like it is off much more. E.g. what feels like 30mph reads 40 on the speedo, not had a chance to get my sat nav on there to test it.
-1 sprocket + speedo
- Thread starter greg
- Start date
Yup, that will happen. Check out the speedohealer site. I think they have a way to tell how far the speedo is off by entering the stock sprocket sizes and what yours now are. I think my Rear sprocket is +2, and my speedo is off by about 10%. The faster you go, the larger the MPH reading will be off.
-1 on the front sprocket calculates out to be a 11.1% speed difference. So if your speedo is reading 45, you are really doing about 40ish.
http://www.healtech-electronics.com/
Last edited:
outasight20
Junior Member
The speedo is about 6-7% over with the stock 16T sprocket. With a 15T sprocket, this error increases to 12-14%. So if your speedo says 80 you are only going 70. At 40 you're really going 35, etc. With a 17T sprocket your speedo will be within 1% at all speeds, but your odometer will be about 6-7% lower than actual distance. Likewise, the odometer is 6-7% higher than actual with a 15T sprocket.
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I have the speedo-healer and it works great. The actual mileage and speed on the spedo are pretty much 100% + or - accurate.
i would add that my bike feels a lot smoother and less lumpy with the -1 sprocket, though the new chain probably made a difference too
think i have a better idea of the speedo after riding home tonight and going past several speed cameras (carefully), and following some cars
think i have a better idea of the speedo after riding home tonight and going past several speed cameras (carefully), and following some cars
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You need a speedo healer. I bought the Heal Tech one. VERY good.
Marcelor73
Junior Member
Yep, +1 on the speedo healer. Love it
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+1 on the Speedohealer.
Mine is flat dead on per the GPS (within .3 MPH).
The newer ones also have a plug in button(iwth long wire) that lets you record your highest top speed and re-set it when you wish. Kinda neat to check..
With the Yamaha adapter, its a plug and play install (plus making the settings). Its easy enough to remove and put on yor next bike too..
