I bought an '04 Skeeter SX170 last year which came with an '04 Yamaha 115 2 Stroke outfitted with a 13.5x21K stainless prop. The boat runs great in my opinion with the exception of holeshot. I don't expect this boat to jump up on plane like an aluminum Xpress or anything but seemed a little sluggish but manageable. The top end with just me and a light load is right 50mph. I'm getting really good gas mileage as well and I guess that is attributed to my RPMs being around 4700-4900 RPM. I did some research and I believe this outboard is supposed to be running upper 5000's which is obviously concerning.
I borrowed a 19K prop a couple of weeks back and the holeshot didn't really seem to improve much if at all. The RPMs went up just about 5000-5100 and I lost about 4mph on the top end. What gives? I would think that this outboard should be able to turn that 21K and 19K prop faster (recommended RPM Range). I checked my outboard mount height and the cavitation plate is level with bottom of the hull when trimmed half-way to 3/4 up.
Could my tachometer be off or set incorrectly? Do you think I really need to drop down to a 17K or 15K prop? Again I'm happy with the boat's performance as is, but worried about undue stress on the outboard if I'm not running at the recommended RPM range. Please help.
I borrowed a 19K prop a couple of weeks back and the holeshot didn't really seem to improve much if at all. The RPMs went up just about 5000-5100 and I lost about 4mph on the top end. What gives? I would think that this outboard should be able to turn that 21K and 19K prop faster (recommended RPM Range). I checked my outboard mount height and the cavitation plate is level with bottom of the hull when trimmed half-way to 3/4 up.
Could my tachometer be off or set incorrectly? Do you think I really need to drop down to a 17K or 15K prop? Again I'm happy with the boat's performance as is, but worried about undue stress on the outboard if I'm not running at the recommended RPM range. Please help.
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