It's a 95 Sidekick 2 wheel drive, I bought it with 215x75 15 on it, to get power band back to close range I put 205x65 15 on it. It calls for 195x75 15. With my GPS to check the speedometer at low speed 0-55 the speedo is 3- 5mph fast, as I go up it increases to 7mph fast at 65mph. I thought by getting closer to factory tire it would bring it inline where it should be, alas I never checked it with the 215's on it.

My 95 Tracker speedo checked with a GPS was dead on running 235x75 15.

X2 what Red said for my 89' Auto trans 2 door

Wild

OK then there must be something wrong with mine. I thought getting back close to factory size wouldn't give me any problems. I wonder if the original owner changed the cable gears at the trans?

Mine read fast with stock tires, 2-3 MPH, 235s were perfect

My speedometer reads fast, but the odometer reads slow.  There is a bad spring in the cluster, one of these days I'll get a new one.

With the 215's on the power band was a joke,had trouble at lower speeds and on inclines it was horrible. With the 205's both of those problems are gone. Odometer is running in sync with the speedo,using the gps it's 11 miles farther the gps is showing.

It's a 95 Sidekick 2 wheel drive, I bought it with 215x75 15 on it, to get power band back to close range I put 205x65 15 on it. It calls for 195x75 15. With my GPS to check the speedometer at low speed 0-55 the speedo is 3- 5mph fast, as I go up it increases to 7mph fast at 65mph. I thought by getting closer to factory tire it would bring it inline where it should be, alas I never checked it with the 215's on it.

You actually went shorter than the stock tire height, when you put the 205s on.

Stock Tire - 195/75R15
Tire 1 - 215/75R15       
Tire 2 - 205/65R15

Overall Diameter of stock tire=26.51 in
Overall Diameter of tire 1=27.69 in
Overall Diameter of tire 2=25.49 in

Actual Speed w/stock tire=60 mph
Speedometer w/tire 1=57.4 mph
Speedometer w/tire 2=62.4 mph
 
So, according to what is above, it sounds like your speedo is reading right where it is supposed to be, since you have shorter than stock tires on it now.
Your readings may not be exactly what is listed above, because your tire heights may not be exactly as what is listed above.  But I don't see a problem with your speedo, or the speedo gears.