Our twin has this issue as well. Definitely needs repair this season. Working on deciding to repair or sell as is and buy new.
I don't have much interest in walking my boat, beyond proving to myself that I can figure out how to do it - which I already have. My boat doesn't behave ideally without some weight up front due to the heavy engine on the back - so I don't spend much time with low fuel and no bow balast. I I just find it interesting to see these boats stand straight up in the air. It almost seems impossible until you see it happen. Greg - what is the "control box"? That must be something on the 20's that I'm not familiar with. Is that where the throttle is located? Why would it crack there?
I think they are talking about the notch where the control sits on the side rail. you can see it some what in the picture below. Daniel
I've found with a boat weighted right (I've tail walked hydrodyne and others) and a low pitched prop, it's all about working the throttle while in the air, I can never leave it in one place. At the end of the video I also turn the boat towards the camera at the end to show the name of our old sponsor, TINUS (marine). Let me know what you guys think... This is a '89 18' Rapid Craft, with a 1999 150 Opti, and a 17' Rav4, a 2x6 pressure treated, and a Whale Tail (hydrofoil) Mike http://www.youtube.com/watch?v=kSsK-HC0kjc I also have an 18' dyne question, what do you think would be an all around better tow boat, a 18' with a 250XS, or twin 115 Opti's??? I don't necessarily want the weight of two V6's on the back of an 18.... Just something I've been kicking around...
I'd like to ask a different question. Which would be the better tow boat, an 18 with the single 250xs or a 20? And, which would be the better tow boat with a single 175, the 18 or the 20? jim
Well, I can comment on twin 115s and how they compare to a big single, but this is on a 20' boat. The big single is quite a bit faster on top end, less drag, less weight. I know our drivers would take the twin 115s for holding swivel/star doubles speed any day of the week. The barefooters prefer the single but don't mind the twin 115s. My only concern on the twins on an 18 would be how much weight you would have to put up front, but it might not be a problem since many 18s have had twin 115s on them. The nice thing about the 115 optis is they have built in oil tanks so you don't have to put the oil tanks in the boat. Bob could shed light on how his 250Xs does, but I don't like the 1.75:1 ratio much for skiing(in single engine apps, with twins it doesn't much matter), but that is the only one the bigger optis are available with. The Evinrudes with 1.86 ratios are much better ski motors than the new 250HO with 1.71:1 in a single engine app. Not that I think the 250XS will be bad, but you could actually probably run a 13 pitch prop on it and still have 42 mph top speed. As to the 175, I think it depends what you want to do. I actually prefer the 20 to the 18 because there is more weight there which I think enables better control. I am guessing Merc smartcraft enables this, but Evinrudes new fly by wire system will have a button whereby you can increase/decrease throttle by 1% at a time. It may or may not be a cool thing.
A merc inline 6 115 is probably 80 to 100 pounds lighter that a modern 115. So that is not a good comparison weight wise. jim
I agree with the Inline 6 not being a good comparison, I don't have anything in the bow (Not even a gas tank) The motors weigh in at around 296lbs each. Daniel
Interesting. That would put you at about 592 lbs of motor on the back. I'm running the single 225 Optimax, which has a dry weight of 512 lbs. I have an 18 gallon tank in the bow and added 60 lbs of balast up there with a full 19 degrees of tuck on the transom (14 plus 5 degree wedge) and still feel a bit more weight up front would be ideal. I'm not sure what would account for the difference. I suppose the twin rig might add some stability and be less prone to porpoise. Mark