Big difference in down and GPS speed?

[rbradley]

had my probe setup for the first time this past weekend. I noticed a bigger than expected difference in GPS vs. down speed. is this normal? I had a gps speed of 3.1 and down of 2.3-2.1 depending on trolling direction. I understand currents and did troll in all directions.

in general what are you targeting for down speed?

[pbrktrt]

Fast enough to keep the lake trout off. Seriously, 2.5-2.8 for salmon and 3.0 and up for steelhead.

[Fowlpursuit]

I alway vary 2.3-2.7 mph but have heard the fish are preferring a little faster troll this year.. 3-3.5. That being said when I was in my preferred location I trolled at 3.3-3.5 while in "search" mode. Once I located fish I slowed it down to 2.5 and started grinding on them.

[Capt. Brian]

I've found that down speeds also vary between brand of probes I know fish hawk and the sub Troll are about 4 tenths different I am not quite sure where the depth raider is in the mix. what I have found is when I hit a fish I look at the down speed and try to keep that the same no matter which direction we are going. That will allow you to adjust your boat speed and compensate for which ever way the current is flowing.

[Fowlpursuit]

Also I should add I pay a lot of attention to my dipsy rods arc.. This is also a great indicator for speed. I often cross reference between gps,down speed and dipsy rod bend..sounds a lil confusing but over time you'll get a natural feel for it.

[LongLine]

GPS speed is not all that accurate as some guys believe, especially at the low end. If it was, it wouldn't hold steady when there's a little chop on the water.