Home › Forums › Bass Cat Boats › Sabre and Humminbird 797cSI, Sonar issues at higher speeds
fish4everAL.
I have a Bass Cat Sabre being built as I type this email. Recently, during my research on the Humminbird site I have read that at higher speeds (not exclusive to Bass Cats) if the transducer is not mounted in right location the possibility of cavitation bubbles (air pockets) on the bottom of the boat could cause the 2D sonar not to display accurate depth readings as you run over 50mph down the lake. Would I be better served to have my dealer contact Bass Cat to install the XPTH 9 HDSI 180 T Plastic Thru-Hull Transducer for Humminbird 797cSi? I think its early enough to have Bass Cat add this to my Sabre that is in the build process right now. Would a through hull transducer fix any potential issue regarding accurate sonar readings relating to faster speeds on my boat? I want to be sure I have no surprises once I get my boat on the water. My dealer, Scott at Brechs Marine in Selma has been very helpful and patient with me about get things just how I like them so I can have a great purchase experience with him and Bass Cat. Please let me know what you all think about the through hull transducer for 797cSI. Is it needed? I do not plan to run over 55mph in my boat. I just want to feel safe running that fast and know how deep I am running down the lake. A side note. Bass Cat should be very proud to have Brechs Marine in Selma, AL to carry their line of Boats. Everyone has been helpful and has made me feel like family with my Bass Cat purchase. Thanks in advance. Tom Moore Birmngham, AL
This link is a post in the FAQ section. Maybe that will help some. Others will be along to help more. KENT http://basscatowners.yuku.com/topic/2107Kent Charles 2002 Pantera Classic & 200 Yamaha VMax
Thanks for directing me to the BC answer site but it does not answer my question regarding a fix to high speeds and sonar readings totally. Hopefully, someone can answer if a through hull tanssducer will be the fix this situation. Also, at what speeds will a Sabre start loosing its 2D sonar readings with a 150 HP motor? Thanks again!
Tom, You ask a hard question to answer. There is no black and white answer. I have a 2007 Sabre FTD, Lowrance 520 in console transducer mounted inside at factory. Any where above 50mph(gps) I lose bottom signal depending on trim angle. At around 55to 60 if you trim down to allow signal you will feel like boat is plowing through water verse sitting on pad and obtaining most efficient operation. This boat runs very high out of the water and rides and handles excellent at any speed. Bottom line if you feel the need for speed know the water you are on or slow down. I dont have any experience with transducer mounted outside. Im on Logan Martin if you would like to look at my set up and or take a ride. Mackey
Mackey, thanks for the response. I understand the sonar speed anomaly is consistent with many boats. I like you feel that trimming your boat to plow through the water is not a fix. Thats why I was hopping a through hull design might be the answer. I hope someone can shed some light on this. Its unfortunate that boats at these prices cannot have the ability to give you a consistent reading with 2D sonar readings at higher speeds. Hopefully, Bass Cat folks can shed some light on this subject. I am willing to pay extra for the the through hull transducers to fix this issue if it works. Buy that I dont mean should work but works consistently at 55mph on plane. If not to be continued.
It depends on a bunch of things. How much air is forced under the hull at speed. Where the transducer is located with respect to this air. etc. My current boat will read the bottom just fine at 75 or so. But if it gets a bit choppy to get more air underneath, the bottom signal starts to fade in and out a bit… The higher you raise the bow, the worse this gets. For pure depth readings when running at speed, I cant imagine a good system wont give accurate depth at 60+. A flasher is better, IMHO, because the computer in the LCD graphs get confused on non-return conditions. Missing one of every two pulses confused them, where a flasher will just show a narrower bottom band bar and keep on working… Note on my boat I use a flasher when running at speed, and the LCD when cruising looking for structure/channels/etc.2008 Pantera Classic2014 Mercury Pro XS 200
I have a 797cSI on my Sabre FTD , it has 2 transducers with a switch to change from thru the hull to the one mounted on the transom . I have not lost bottom contact going 60MPH+ when using the thru hull transducer – I use the the outside transducer only for SI reading (10 MPH and slower) Hope that helps
CNCBass, Are you saying that your through hull transducer will not work with SI imaging for the 797cSI? That is a lot of money just to have effective 2D sonar readings at higher speeds. I might be assuming some things here but to me I would think that XPTH 9 HDSI 180 T Plastic Thru-Hull Transducer for Humminbird 797cSi should cover both criteria for 2D sonar and SI. Although, I am glad to read your accurate sonar readings with the through hull transducer at higher speeds. Just stumped that it doesnt work with SI imaging. Was the XPTH 9 HDSI 180 T Plastic Thru-Hull Transducer for Humminbird 797cSi not out when you installed the through hull transducer? Everyone, thanks for your posts. Its helping me be more informed from you experience. Thanks, misr12
I like oldtimer use the flasher for running at higher speeds. I have never had a graph that could respond at higher speeds consistenly on any boat I have had. I use the LCD flasher built into my lowrance 332c. I guess because it is just a simple ping to show depth that it works better at higher speeds.Jason Desertdweller.com Get Your Bass in the Boat!
I am no expert, but I believe the Side Imaging system is designed for low speed. Using your menu to select 100 MHz transducer only may solve the bottom lock problem. I dont have a 797, but a 787 but it intermittently breaks lock on my P II at about 50 MPH. I have a flasher which provides accurate reading at speeds greater. As I read these posts it occurred to me that using the single beam may preclude losing bottom lock at speed. I hope to go fishing tomorrow and try the single beam and will let you all know.
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