X17 Setup Help

[ThreeRiversRunner]

I have an 2004 Xpress X17 with a 2003 Yamaha 115 fourstroke, 6 inch manual jackplate set 4 1/2 below pad. I've tried from and 18p up to 21p prop and can't get more than 40-41 mph on GPS by myself and no tackle. There's not a dimes worth of speed between any of the props but the 18p gets out of the hole a lot better when the livewell is full. The 21p ran at about 5600 rpms and the 18p is at 6000rpms. I've seen that many of you get 50+ mph with the same setup. Any ideas why my rig is so slow? Thanks for any suggestions.

[1Holeshot]

Prop too low. Raise to 3 1/2" below pad and try again. After that raise in 1/4" increments until speed drops or rpms too high then lower 1/4". You will be much happier and there is no reason you should not run 50+ with your combo.

[fishingram24]

My last Xpress was 2012 X17 with F115 and hit 51-52 anytime. 6"jack plate with motor set at 3 3/4" PTP, turned the Power tech 19" prop to 6100 rpms. So same boat, motor but way more speed. Raise the motor but I don't think it helped mine as much as you are looking for, might have to big of a weld bead on the pad area at the bottom of your transom. Know for a fact that to much weld will slow it down a lot.

[ThreeRiversRunner]

Thanks, to both of you. I'll try raising to 3 1/2 below pad and adjust from there. I'm thinking I may just have a slow lemon(maybe weld bead). I've got a couple of buddies with Xpress boats and they perform great.

[Arkyarcher]

Make sure the bottom is flat back 3' to the transom, mine was pushed up right before it and made a hook that slowed me a lot.