High speed wiggle
 

What is this boat doing? I'm on it now. Finally running awesome. New prop with a bit of cupping added. Gets me at 4500 rpm. When it's planed out at about 62-65 mph. it does this wiggle. It's scary. What is that? I back off the throttle cause it's not predictable.

Chine walking it sounds like. Can be very dangerous.

Keep backing off or u will be upside down!!

It's very bizarre. I have years of runnin my drag cars. And know what to push through. I drive the boat to my comfort level. If I'm uncomfortable. Something isn't right. Didn't like that feeling. Is it a limitation of the hull? Or am I doing something wrong?

Are you turning the props in or out?

Could be a combo of both. Bajas aren't the fastest hills or most notorious for great handling at high speeds. Some extremely experienced guys have been able to drive through it on some hulls. However huge gamble. I believe the 22 donzi at the shootout was trying to drive through it and he has done it before.

I'm not sure what that means. It's a right hand mirage plus with a bit of added cupping.

I'm more interested in knowing if I'm doing something wrong. I'm not gonna put $$ into it to go faster. I will have a different boat by spring. I really like a 2000 formula 382 I looked at.

I'm wouldn't doubt it my lack of experience. Lol.

Does the boat have external steering?

Describe wiggle. chine walking is where the boat bounces from one side to the other and it can start out mild and get wild. If you have tabs does the problem go away if you put them down till they just touch the water. It also could be a loose steering linkage IF you don't have external hydraulic steering. The top pivot pin in the transom assembly gets worn badly on old boats. If it is badly worn and you tighten the two nuts at the top more than two turns you will likely break the gimbal ring.

Yes. That describes it. It's a side to side movement. It starts subtle. Then progressively became more pronounced. I would back off. Then accelerate until the "wiggle" started again. Like a trial error thing. Trying different things. Examples- steering with a lighter touch. Micro adjustments to the trim. Very small trim tab adjustments. When it got uncomfortable. I would back off and try again. It irritates me I couldn't figure it out. I got frustrated after an hour or so and gave up. I don't have external steering.

Try different props.

What prop are you running?

4 and 5 blade props don't paddle as much as 3 blades. Most Baja come with 3 blades. External steering and different props may be all you need. Trim tabs may help too.

Don't give up yet. Learn on the smaller boat before you go big.

Turning the prop in or out refers to a twin engine application and the rotation of the props.

From Powerboat Magazine:


Top speed for the H2X was 72.6 mph at 5,120 rpm. That number came courtesy
of a 425-hp MerCruiser 496 Mag HO engine with a Bravo One drive spinning a
Mercury Mirage Plus 14 5/8" x 23" three-blade stainless-steel propeller through a
1.5:1 reduction.
Time to plane was a respectable 4.3 seconds—a four-blade Bravo One prop might
improve it a tick—and in 20 seconds the 24-footer ran 67 mph. Consistently impressive
in midrange acceleration tests, the 4,000-pound sport boat ran from 30 to 50 mph
in 5.4 seconds and from 40 to 60 mph in 6.2 seconds.
Baja remains one of the few performance boatbuilders that doesn’t offer steppedbottom
models—and it doesn’t seem to matter. Riding on 21-degree conventional hull
with four strakes, slightly negative chines and a delta-pad keel, the H2X handled precisely.
It slashed slalom turn after slalom turn, responding instantly to steering input.


CENTERLINE 24'
BEAM 8'4"
WEIGHT 3,900 POUNDS
BASE PRICE $47,825
PRICE AS TESTED $68,041
ENGINE MERCURY 496 MAG HO
TOP SPEED AT RPM 72.6 @ 5,250
TIME TO PLANE 4.07 SECONDS
ACCELERATION ZERO TO 15 SECONDS 60 MPH
MIDRANGE ACCELERATION 40 TO 60 MPH 6.2 SECONDS
Baja Marine Corp., 1520 Isaac Beal Road, Bucyrus, OH 44820-9604 P O W E R B O A T M A G A Z I N E • J U L Y 2 0 0 1

Getting (and staying) on the pad takes some seat time from my experience. Don't push it. If you feel uncomfortable with the steering wheel, passengers with a grab handle are probably puckered to the seat.

Also, realize the testing numbers posted were most likely one/two people, 1/4 tank, and likely early morning when water was flat and temps and humidity were low.

The difference between full tank/80*/3-4 people to 1/4 tank/60*/1 person is about 4mph in my Progression (pad bottom, variable dead rise). I can run about 60 on any given day. When it's early, cool, I'm light on fuel, and I'm alone, I've seen 64... But it requires a very short and fast bump of the wheel to the left when it first starts to walk, and then the training wheels come up after the motor is laying out a tail spray about motor height (won't apply to your I/O, but it indicates a sweet spot). And all of this is after switching from a Mirage to a Tempest to a Mirage + to a Mazco HP4, and then back to the Tempest.

Use the trim tabs . Start with them all the way down with the drive trimmed to a medium position. Then ease the tabs up. If it persists you will need to counter steer. Counter steering is something only experienced outboard drivers are good at. The boat will cat walk back and fourth and carry the nose high, but will not chine walk. If you do not have experience counter steering , change the boat set up to a more usable set up . You should also contact previous owner if the boat us how you got it from them. Also check all the drive bushings and mountings to make sure there is Absolutly no play in the drive or steering

I'd start with checking for play in drive and steering components, if those are all good then I'd be thinking about adding hydraulic steering.

Just put the tabs down until it stops and then make note of the setting. From that point on always have the tabs no higher that that setting and you will be ok.

Agree about checking the drive and steering for excess play. Ideally, you shouldn't have any movement when you try to push the drive from side to side. I think hydraulic steering is nice but overkill on a single engine 60-70 mph boat.

Try using different tab settings, some boats will run better without the hinderance of tabs making the problem worse. Establish a speed where it feels unstable and play with tabs and wheel at that speed then move up a few mph and keep playing.

Never try to drive through the walking, pretty risky stuff. Learn to control it instead. Try sharp but very small movements on the wheel in both directions, it sort of makes the boat do what you're telling it to do rather than let it slap against the water and bounce from side to side. Wiggle the steering wheel.

If she starts to feel a bit loose, you can pull into a very gentle turn to push the hull against one side and stabilize it then slow down to a safe speed and start again.

Just because a boat chine walks doesn't mean it's a bad boat or the set up is wrong, many boats need practice to drive at speed. Learn slow, don't take crazy risks.

RR

One easy thing to check, don't always trust your trim tab gauges. With the boat on the trailer, set the tabs level with the bottom of the boat. Stand back and have a look or put a straight edge up against them. Then look at the gauges and see what they say.

This is your 'level' point, make a note on the gauges with tape or a marker if they aren't reading the same. If your tabs are adjusted differently, could throw a few things out of balance at speed.

RR

High speed wiggle? Dam, I thought this was about Fountain Skanks!

Padraig

that could make things worse quick, getting the rear of the boat higher could cause bow steer in the chine walk situation. and hook that boat around. Play with props and drive height, and check the bottom for hooks or rocker. Also having too much pitch prop and not running in the meat of the RPM range could cause handling problems

Plus 1 on checking the tabs. I was having some problems using my tabs. A buddy of mine suggested that I check them with a straight edge while on the trailer. Well they were off. Port side tab at 6 dots,starboard side tab 4 dots on the indicator. That puts them level with back end of the boat. I now run them at 5 and 3. All good. I have a 21ft superboat with a 509 efi. Full hydraulic steering. Its a drivers boat for sure. I was running a bravo 28p pitch. What my buddy noticed was the prop was actually lifting the back of the boat. I had the blades shortened from 15 1/2 to 14 7/5. Made a world of difference. Hope this helps.

If it's a wiggle and not a wobble you should be fine. :drink:

Thank you all. I had a smooth lake and was alone Monday. Spent a bit of time playing around with it. Tether on and life vest of course. I'm a little embarrassed to say this but..... I think it's mostly my inexperience. Here's why I think that. After a bit of experimenting with a little progress. I decided to eliminate things one at a time. All logical like. When the boat would start the "wiggle wobble" I took my hands off the wheel and the throttle. And it went away!!!! Apparently the boat can drive better than me!!!!
I'm thinking I'm prolly white knuckling the wheel when it starts. Damn I feel dumb.
I am going to check the things suggested. And try the additional tips tomorrow. I will get good at this at some point. I am really enjoying the boat and learning. I truly appreciate all your help.

Thank you
Mark

WORD of advise - Don't EVER take your hands off the wheel unless you are at no wake speed. OH and the same goes for the throttle. I had my boat do something real strange and if I had not had my hands on the throttle and wheel I would have been in the trees. I was running a river making a long sweeping RH turn and the boat suddenly turned R.
I chopped the throttle and turned L and drove out of it. I don't know what a hook feels like but the rear of the boat didn't slide out - the front just turned. I am learning how to drive this boat all over again. I was by myself and was driving aggressively but didn't think I was that out of shape.

Things happen with different passenger loads and previous experience. Back in 1957 I had a buddy that made multiple passes through a 'wiggly' channel by himself at full speed during daylight. So he loads the boat up with his beer drinking buddies (me included) and makes this pass at night. Guess what happened? The engine must have been at 15,000 RPMs when we were upside down crashing into the water missing the first curve. The motor stopped real quick when water entered the intake.