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NORTHERN LIGHTS
04-20-2006, 04:45 PM
I just bought a new lift for my ps 197. The bunks on my trailer are 48' apart and the boat sits snug on the strakes. The another set of bunks start about halfway up the trailer to cradle the rest of the boat.
The bunks on the lift are 14' long. Should the bunks be placed at the 48" like the trailer or moved in on the flat part of the hull? If i move the bunks in it looks like much more of the bunks will be cradeling the bottom of the boat. Make sense? Any help would be great!!!

Evan Jones
04-20-2006, 04:59 PM
I think mine were about 38" apart in the back on the '97 205 trailer. I made the lift bunks the same. The trailer has 1 piece bunks all the way to the front. So I guess I'd move them in. I have mine so they are just outside one of the strakes so as I slide the boat on the bunks in kind of self-centers.

NORTHERN LIGHTS
04-20-2006, 05:01 PM
I think mine were about 38" apart in the back on the '97 205 trailer. I made the lift bunks the same. The trailer has 1 piece bunks all the way to the front. So I guess I'd move them in. I have mine so they are just outside one of the strakes so as I slide the boat on the bunks in kind of self-centers.
Looks like identical lift hewitt --high lift
how deep do you keep your lift in comparison to the bunks
I.e. 6-8 inches above the cross bar?

east tx skier
04-20-2006, 05:02 PM
I have an older boat/trailer, so my trailer only has two bunks. My bunks (and our lift) has a twist in it to conform to the hull. Our cradle/lift bunks are about 14' as well. I know the 197 trailer is different. But that sounds difficult to do on a lift. In the owners manual, there are some specifics about lifting and what surface area (250 sq inches IIRC). Also, bunks have to be continuous for a certain length IIRC. Check it out in the DL section.

The slightly twisted bunks work great for us. But there could be a reason they went to four on the newer boats of which I'm not aware.

NORTHERN LIGHTS
04-20-2006, 05:05 PM
it just seems to me that i will have to move the bunks in to the flat part of the hull to grab the most surface area I can. I'll check out my owners manual, I didn't know they had lifting specs in there. Thanks!

east tx skier
04-20-2006, 05:08 PM
it just seems to me that i will have to move the bunks in to the flat part of the hull to grab the most surface area I can. I'll check out my owners manual, I didn't know they had lifting specs in there. Thanks!

I'd always heard to keep the bunks under the stringers. But we just told the guy who designed the cradle to model it after the trailer.

NORTHERN LIGHTS
04-20-2006, 05:08 PM
I have an older boat/trailer, so my trailer only has two bunks. My bunks (and our lift) has a twist in it to conform to the hull. Our cradle/lift bunks are about 14' as well. I know the 197 trailer is different. But that sounds difficult to do on a lift. In the owners manual, there are some specifics about lifting and what surface area (250 sq inches IIRC). Also, bunks have to be continuous for a certain length IIRC. Check it out in the DL section.

The slightly twisted bunks work great for us. But there could be a reason they went to four on the newer boats of which I'm not aware.
that pic is the exact reason I bought a lift--- '93 and beautifully clean!!!

NORTHERN LIGHTS
04-20-2006, 05:11 PM
well thats what threw me off when i looked at the trailer. The dual bunks really hug the boat so i'm a little confused as to what to do with the lift. I also have heard to keep the bunks under the stringers, which would make me believe I should pull them in a little.

east tx skier
04-20-2006, 05:33 PM
Thanks! When it comes to following the trailer design versus putting them under the stringers, I'd say go with the trailer design based on the statements in the manual. I'm no expert to be sure, but MC designed these trailers to properly support the boat, so it would reason that they are perfect templates for lifts cradles.

If you see how the bunk supports are angled in the front and straight up and down in the back, that's also providing for some twist as well. The lift cradle has two bunks stacked for extra rigidity since there is no center bracket like the trailer has.

Granite_33
04-20-2006, 05:37 PM
Personally, I think the closer in, the better.

Though the hull is incredibly stiff, the wider out the bunks, the more inward stress there will be on the hull, IMO. I don't notice this on my X-9, but my old Maristar 210 I noticed that the windshield pinched in about .5" when the boat was on the lift.

I have my bunks just outside of the inside set of strakes. That way, when I lift the boat, I can center it at the same time because the strakes snug inside the bunks and can't move. Keeps the boat nice and centered on the lift.

Cheers.

88 PS190
04-20-2006, 06:32 PM
Put them under the stringers, Its exactly how they have them at Ski Bennetts, and i'd think they know how to treat a ski boat.

The demands placed on a hull when trailering are much greater than those exposed to a boat on a lift, one no bumps, two no turns, even a kid jumping on a boat on the lift is going to do precious little in comparison to the boat compared to what it must indure when a boat goes through on an average highway trip to the lake.

NORTHERN LIGHTS
04-21-2006, 07:29 AM
thanks to all---

jimmer2880
04-21-2006, 01:07 PM
Put them under the stringers, Its exactly how they have them at Ski Bennetts, and i'd think they know how to treat a ski boat.

The demands placed on a hull when trailering are much greater than those exposed to a boat on a lift, one no bumps, two no turns, even a kid jumping on a boat on the lift is going to do precious little in comparison to the boat compared to what it must indure when a boat goes through on an average highway trip to the lake.

That's exactly what I was going to say. :D

RobertT
04-21-2006, 01:30 PM
I have a Hewitt lift, and my bunks are not close to the same location as the trailer. Mine are about 36" apart, they cradle the hull about 6" in from the strakes (if I am saying it right). Another thing that I did was I chose not to use the aluminum bunks. That would have caused point loads, with wood it flexes and cradles the entire hull properly. Just my uneducated opinion, but what you are looking for is to spread out the forces over the largest area possible. Period. Point loads by using a stiff bunk that is not perfectly made for the hull would be worse. The trailers are made specifically for the hull, that would be tough with a lift.

I loosened the swivels up and put my boat on the lift, and lifted it up. This forced the bunks into a little twist, and made them follow the hull perfectly. I tightened them up, and they are locked in that way.

One other side note is that since my trailer bunks and my lift bunks are slightly different, I can easily wax 100% of the hull properly. I bought a suction cup thingy from West Marine that I use to hold myself onto the boat and I actually clean/wax the hull from under the boat lift once or twice a year.

MC may say different, and certainly mirroring the trailer support system is ideal, but that would be a lot of tedious work to do on a lift in my opinion.

Evan Jones
04-21-2006, 02:12 PM
[QUOTE=RobertT] Another thing that I did was I chose not to use the aluminum bunks. That would have caused point loads, with wood it flexes and cradles the entire hull properly. Just my uneducated opinion, but what you are looking for is to spread out the forces over the largest area possible. Period. Point loads by using a stiff bunk that is not perfectly made for the hull would be worse. The trailers are made specifically for the hull, that would be tough with a lift.[QUOTE]

With such a heavy boat, and long pieces of aluminum, you get quite a bit of hull-hugging flex from the stock bunks. I was surprised there was so much flex.

NORTHERN LIGHTS
04-21-2006, 02:27 PM
i ASKED THAT VERY QUESTION ABOUT THE ALUMINUM BUNKS AND THEY SAID THAT THE ALUMINUIM WILL FLEX. iT GOOD TO SEE A SIDE SHOT OF YOUR BOAT ON THE LIFT. THAT IS THE IDENTICAL LIFT i JUST BOUGHT. tHE REASON FOR THE ALUMINUM (ACCORDING TO THE MANUFACTURER) WAS THE ADDED WEIGHT LOAD IN THE MIDDLE BECAUSE OF THE ENGINE IN THE MIDDLE. i'VE BEEN CRAWLING UNDER THE BOAT ALL DAY MEASURING AND IT LOOKS LIKE +/- 38" IS WHERE THE BUNKS WILL BE PLACE.

NORTHERN LIGHTS
04-21-2006, 02:30 PM
[QUOTE=RobertT] Another thing that I did was I chose not to use the aluminum bunks. That would have caused point loads, with wood it flexes and cradles the entire hull properly. Just my uneducated opinion, but what you are looking for is to spread out the forces over the largest area possible. Period. Point loads by using a stiff bunk that is not perfectly made for the hull would be worse. The trailers are made specifically for the hull, that would be tough with a lift.[QUOTE]

With such a heavy boat, and long pieces of aluminum, you get quite a bit of hull-hugging flex from the stock bunks. I was surprised there was so much flex.
Now that I look at it real close you can see the flex of the bunk. Hewitt knows what there doing so if they it good to go then i'll go with their recomendation. My bunks are alum. and 14' long.
I don't want to be a pain in the *ss about this but this lift is gonna hold my pride and joy(with the exception of my son).
my wife came in a close 2nd!

jimmer2880
04-24-2006, 07:55 AM
[QUOTE=Evan Jones]
....I don't want to be a pain in the *ss about this but this lift is gonna hold my pride and joy(with the exception of my son).
my wife came in a close 2nd!

I hear you. My wife is jealous because she thinks I adore my boat & dock/lift more than her ;)