2015 Prostar - Anyone Grinding the Rudder?

[skibug]

We are trying to set up a 2015 Prostar. The rudder does not have an adjustable tab; and for the record that is ridiculous. That decision by Mastercraft is just absurd. How is there any possible downside to having an adjustable rudder? But I digress; has anyone had to grind the opposite side (port side) of the rudder to get some of the torque out of it. Seems as though this would help our situation with how it drives. It seems to be very sluggish to respond to placement from the 1-3-5 side. The response is very asymmetrical. I would expect some; but, not as much as we are experiencing.

 

Any feedback would be much appreciated.

[RichardDoane]

my 2014 has been perfect w/o any grinding, but if you feel your 2015 needs a little tuning, don't be afraid, just work slowly a little at a time, and test drive after every session

[skibug]

@richarddoane thanks. I know Mastercraft has touted that they have perfected the rudder and there should be no need to hit it...but, this thing is not driving well at all. We need the boat to list to the port side significantly to get it to track without sliding too much or getting stuck on one side of the course. We have an additional 60 lbs to 70 lbs, above the drivers weight, on the port side; meaning if we have a 200 lb driver we have 270 lbs opposite. It makes it driveable; but a ways off from good.

[Razorskier1]

Are you using a 3 or 4 blade? I have found 3 blade generates less rudder load.

[kurt]

@skibug in the back lift up the access cover to the rudder and move the steering cable from the outside hole to the inside hole . This will make the steering much more responsive . You just need 2 end wrenches to do it . Also if you only have a ski rack on the drivers side and you stack all your gear as well on that side the weight does add up.

[skinonstop]

My 2015 is perfect and hasn't needed any grinding.

 

[skibug]

@Razorskier1 4 blade, came with the boat. Is a 3 blade tournament approved; and , is it what will be seen out there at the tournaments?

 

@kurt thanks for that heads up on the rudder cable hole, we will definitely try that prior to grinding. We don't keep any gear in the boat so the loading of the driver side is not an issue.

[Texas6]

My 2015 has some fairly assertive rudder load, but don't view it as a problem, just more than I am accustomed to. The boat definitely prefers to turn right, but my 197 was the same way. I would be curious to hear if the steering cable adjustment relaxes the load somewhat

[LLUSA]

@skibug the ProStar was approved with both 3&4 blade props, 3 blade if you have big time jumpers otherwise 4 blade, we have a 200 foot jumper on our lake and run 7&3 on the boat and it works

[Razorskier1]

@skibug - 3 blade is approved.

[LeonL]

Apparently it's not unusual to find a '14 or '15 with excessive torque load on the steering. Some are OK. I drove a '14 that just wore me out pulling 10-12'skiers. Arm was tired. Some just need that torque relaxed a bit. Weight shifting isn't the answer.

[Texas6]

@LeonL, by "relaxing the torque a bit" do you mean just letting it break in, changing the steering cable from outside hole to inside hole, or are you referring to grinding. I love the way my 15 drives, but I think the rudder load is a bit more excessive than it needs to be

[skibug]

@Texas6 @kurt ours does not have a set of holes on the rudder arm, it is a slot. Not quite sure how to adjust it. We loosened the lock nut and tried to slide it but it seems there is something forward of what we can see (under the floor towards the engine) that must be keeping the steering cable secured. Not sure how to adjust it.

[Roger]

It doesn't look like this???

 

[skibug]

@Roger, probably. Those big rubber washers cover up most of the second hole making it look like a slot. Thinking about it, that is pretty stupid on my part....a slot wouldn't work in this type of application. I will have to go look at it again tonight. Thanks.

[Chuck_Dickey]

If you zoom in on the picture, you can see the second hole in the tiller arm. You do not new to move the cable mount that's up under the floor.

 

The rudder torque is set by the casting and you shouldn't need grind it more especially if you're going to pull shortline skiers. Grinding on the opposite side will reduce the torque and the boat will wallow down the lake. The proper torque greatly helps true tracking in the slalom course.

[Andre]

Wasn't there a fix talked here before ? Like 2 teflon washers or something like that?

[skibug]

@Chuck_Dickey, Thanks for the feedback. I was not thinking about grinding the drivers side of the rudder, with the chamfer. I am contemplating grinding the opposite side. I do pull short line skiers everyday (38, 39, and 41 off skiers); but, this seems to be way more torque then I would prefer. I am going to move the the steering cable to the inside hole on the tiller arm and see if that helps.

[LeonL]

@Texas6, poor wording again on my part. I mean actually doing something. @Chuck_Dickey, your boat may not need grinding, and maybe none "should" but some of them definitely do. As I mentioned earlier, some of them will just wear your arm out. That's more than you need to pull short liners.

[RichardDoane]

remember to make sure "prop type" is properly set in the ZO settings, there's options for both 3 blade and 4 blade

[dbutcher]

Drive it for a while as is. You may get used to it. I had a 14 Prostar that I thought had too much torque when I first got it. In less than a month I liked it. I tried the inside hole on the tiller and didn't like that. If memory serves me, the inside hole reduced the steering wheel travel needed to move the rudder, but it required more effort - especially going against the torque.

[slow]

For $80000 can't these boat manufactures individually tune you're boat to perfection on their test lake. Is that to much to demand.

[TFIN]

The ProStar rudder is actually hand-tuned at the factory and water-tested as you mentioned. Some drivers prefer more pull, however, I have never found the need to additionally grind the rudder on any of my boats.

[LeonL]

Moving the connection to the shorter hole will NOT reduce effort, just increase it.

[skibug]

I am not so worried about effort (although it does play into it); I want more exact response in a short distance. Right now, out of 1-3-5, I am having to rotate the wheel way more than I want to and it is very slow to respond.

 

I have never driven a boat like this where you had to be so far ahead of the skier to keep in rhythm; and then, if you do get a little out of sync and lose that margin of being ahead, there is little hope of recovering.

[Texas6]

I'm definitely not having that problem; bummer

[skibug]

@Texas6 @kurt moving the steering cable to the inside hole made a ton of difference. Much more responsive with much less input into the wheel. That seems to have done the trick. Although we still need about a 60 lbs offset of whatever the drivers weight is; meaning the boat has to tip to the port side to get it to track and feel balanced when on plane. Thanks, to everyone who responded, for all the help.

[Texas6]

@skibug, fantastic news, thx for the reply. I use a port side ballast in mine which hopefully will help the weight offset. I now have a project for tomorrow! Super helpful, will reply back after I'm done

[kurt]

@skibug , Great glad it worked

[skibug]

@kurt @Texas6 another question. Are you guys running with the front cover off? Air dam inserted? etc. Have you experimented with this at all?

[kurt]

@skibug my front cover has only been off once for a family trip. I don't believe I have driven any of the '14 , '15 or '16 prostars in the course with the cover off.

also I looked at my counter weight and I have 160 lbs I put tight to the gunnel if there is only 2 of us skiing , I take it out when we have 3

[Texas6]

My front cover has never been off. Really don't think that impacts rudder load however, but a good thought

[6balls]

Wouldn't it have been far easier to have an adjustable rudder? No grinding necessary...adjust to your preference. Not a new idea for sure it's on my 15 yr old SN 196.

[skibug]

@Texas6 I was just wondering about weighting the boat. I noticed that the tracking fins on the prostar are much further back than other boats. The fins start under the pylon and stack up toward the stern. That means, depending on the balance of the boat, too much weight up front may have diminishing results on how it tracks and responds to wheel input. Just some thoughts and questions as I try to improve the way it drives. The other issue is wake symmetry. I still need a 60 to 70 Lb offset to the passenger side to get the wake curls (rooster tails) to be symmetrical.

[LeonL]

@skibug are you saying that you need 60-70 lbs over and above the drivers weight on the passenger side to get symmetrical wakes? Is the boat visually off level without the weight? That seems kinda bad to me. Does any of you other guys who have MCs need this much extra weight on the passenger side to balance wakes?

[6balls]

@leonl only 60 lbs...not over and above driver weight added to passenger side if only a driver in boat.

[LeonL]

All boats need some weight if there is only the driver. Even SN which has opposite prop rotation needs weight if only the driver is in the boat. Normal. Thanks for clarification @6balls.

[markchilcutt]

@skibug when you say 60 - 70lbs offset are you talking with or without a passenger in the boat?

[skibug]

I mean the boat has to tip towards the passenger side with 60-70 lbs above the whatever the driver's weight is. I have been talking to some very experienced tournament drivers who have confirmed that some boats need this offset.

[6balls]

@skibug I weigh 190 are you telling me they are putting 250 lbs on the passenger side if no observer??? That seems bizarre.

I think @razorskier1 has a 50 lb bag of shot that he has for passenger side of his Prostar to level out as he and @razorross3 are often skiing without observer.

[skibug]

@6balls, yes.

[RazorRoss3]

We have 100lbs of shot that we move around. If no observer it's all the way to the passenger side. If there is an observer it's mostly centered a little to one side or the other depending on who is driving and who is spotting. Has never been horrible though.

[Razorskier1]

I use 100lbs, as noted above. That is plenty and I'm 190lb driver.

[LeonL]

@6balls that what I interpreted @skibug meant in the beginning. To that I say, there appears to be a significant problem. I do know that due to prop rotation direction in a MC more counter balance is required than in a SN.

[skibug]

I was told this was the last 2015 made. I would think, if the rumor is true, that the mold would have been gone by the time this one was made. If there was too much rudder torque; wouldn't it be pushing the boat with "yaw" down the course. Meaning you could be going straight but the boat would not necessarily be in line with the axis of the course. Then, this would cause one of the wake curls, in this case the port side wake curl, to be out of symmetry?

[LeonL]

Off topic just a tiny bit. Off brand is more like it. I once saw a Carbon Pro running down the course like described, kinda dog walking as we say here in the country. Front not in line with the back.

[skibug]

Took the leap of faith today and really glad I did. Ground the left side of the rudder; MUCH BETTER!!! It didn't take much either; just a couple light passes with the flapper wheel from the top of the rudder to about half way down. I would highly recommend for those experiencing what they feel is too much rudder torque.

[LeonL]

@skibug, I knew by your first post that it needed rudder grinding. There are some guys on here that apparently got boats that didn't need it. I've driven 2 '14s and one '15 and all three had too much rudder torque. However this does not solve your problem with the boat not running level without adding a significant amount of ballast to the passenger side, but improvement is improvement!

[swc5150]

@skibug

So glad I found this thread. I did all the other tweaks to dial in my steering, just lastly looking to remove some of the heavy rudder torque. Any special grit you'd recommend for the flapper?

[skibug]

I think I used 80 or 100...just take a skim pass at a time. Don't hog it out.