super light tunnel hull, 20"shaft set - up

[ricklem]

hello,
I am brand new to this forum stuff. Please forgive any protocol goof ups.

I recently ordered a 13 foot DUX boats PD-400 inflatable. Haven't even seen it yet. All of these boats appear to have been designed for a 150 lb, 40-50 hp, 15"shaft outboard, running a surface peircing prop (I barely know what that is).

It also appears that all of the new 2006 40-60 hp motors are 250 lb. 20" shaft models.

Does anyone have experience yet running these heavier longer outboards?
What differences and tradeoffs does a propeller make in speed, acceleration vs. water toy/skier towing applications. I realize books can be written about these topics. anyone know where to start??

[Fast Fred]

the hulls a dog, a 3 leged dog at that, start by gettin your self a REAL SLT MODA. the prop needs to be CUPPED, then drop it down a hole to tow.

[ZRX]

What are some of the BEST running hulls???

[Fast Fred]

the nicer hulls have a 70hp max, you can still get a Merc 15" 59cube 60hp 2 stroke, New, in the box. if by chance that 20" set up gets goin good it's just guna barrel roll when ya try to turn it.

In racing thay wont let ya off the trailer with a 20" shaft on a SLT, cuz it's just guna rollover in the turn.

any who, thares a ton, a TON, of SLT 15" power out thare, name your flavor

[ZRX]

FF, I was wondering what name brand of hulls are the best? How are the aquarius hulls?

[Fast Fred]

5 brands are at the top, some for Quality and some for Speed GEMINI, and MAKO/BALISTIC, them to are about the nicest made, a little heaver than the rest, AQUARUS is about the fastest, CEAZER and THUNDERCAT are well in thare
as well.

[ZRX]

Do you have any links where to purchase these ? What is a good price for a used one? Do they ever start to leak air? or are they extremly durable ? Are there any problems to look for on a used one?

[Fast Fred]

used is hard, if it's not Loved and raced to death, it's nuglected full of water
and sunburned. the BURG got some NEW ones, take your time drillen the stainless transome on that hull. a nice used one if ya can find one 2000 -2500
NEW thay start about 3500-up. mother nature Allways wins, all ways. thay all leak, all of them, some more than others.

[ricklem]

Thanks for the reply, Fast Fred. So I bought a DUX dog? A three legged dog? I hope it's not as bad as a 3 legged dog, in a wheelchair, going up hill. But then I'll be too busy barrell rolling out of the corners with the 20 inch shaft outboard to notice I'm in last place.

I hear you can get plenty of new overseas motors shipped in. For now, I think I'd prefer a 2006 emissions compliant four stroke or direct injection 2 stroke. Has anybody done any testing on these new, heavier, longer motors? What is this tendancy for a 20 " shaft outboard to "barrell roll on a turn, as Fast Fred warns. Is that a function of the extra weight or longer shaft, or both? What about mounting on a taller transom?

And what does "MODA", as in "a real SLT MODA", mean?

Thanks for the tip on raising or lowering the motor depending on use. that makes sense. Thanks.

[Fast Fred]

the TLDI 50hp short w/a manual bracket, works well. with a 20" shaft on a hull
designed for a 15" is a compramise at best or stiches or worse. good luck with it.

[charlie the wonder dog]

Heard of a Tohatsu dealer that fitted the TLDI powerhead to a regular 2 stroke short mid/lower for thundercat racing and were quite impressed.

[ricklem]

Thanks for the reply. I have heard all sorts of things about these slt boats and 20" vs 15" shaft motors. I have heard that Inflatable Marine Products (Sea Wolf) can get new Tohatsu 50 TLDI engines on a 15"shaft ith tillers,from the factory. I have heard that the apba is discussing rule changes to allow 20" shafts for the racers. Does anyone have any experience with a new (or old) 20' shaft outbaord on a slt??
Fast Fred says they cause a boat to "barrell roll" on a turn, Mr. Bob Barbieri, of Mad Dog Inflatables says they have tested them and they work just fine.

I have a boat on order. they look like a blast. Yet they have been around for a decade or more and they seem virtually non-existant in the US, while a review of zapcat-racing.com would make you think there are millions of them in England and South Africa. Thanks for the input

[berg969]

i was at the apba meeting and the 20" was discussed and it will never be allowed to race.

[ricklem]

Thanks berg969,

Could you please share why the 20"shaft engines will not be allowed. It seems self defeating for building US interest, since that is the only length of new engine you can buy with a warranty in the 50hp range. There may be very good reasons, I just am clueless as to what they are. I was really hoping to get something going in the state of Iowa with these boats and races. RickLem

[berg969]

firstly in racing there are no warranties and if you make a warranty claim on a raced engine that is wrong. the motors sit high enough off the transom as it is adding another 5 inches will put way too much stress on the transom the tiller will be way to high and your center of gravity will be messed up as hell. as for no 15" motors available i can get you whatever you want or need and it will be cheaper than the local dealer.

[ricklem]

Thanks again. I thought the extra 5" would all be below the waterline on the 20" engines. I can see where that adds a longer lever arm to twist on the transom. Is that really an issue? I've heard it so many ways. Since there are no organized races in central Iowa, US, I won't need to worry about violating the "no racing" warranty breaker. A warranty is important to me as my 1999 Yamaha 1200 XL PWC is on its 4th or 5th rebuild. I would like something very durable. I'd still like to beat all of my old PWC buddies tho. What would you recommend?

[berg969]

if you put that 5 inches below the waterline the boat will handle like crap if you can even get it on plane. as for the transom the older boats have wood between the stainless and the tubes which if you put more leverage on would cause it to start to rip out. the new generation of boats coming out of south africa now have full stainless transoms which 6" side pieces which give alot more grip and help keep the transoms stiffer. any stock Yamaha will live for years when taken care of on an inflatable but any modified motor is a different story. i have had motors that were bought new in 1990 and are still running on a boat today with only regular maintenance. the pwc motors on the other hand are tuned pushed to the limit from the factory. a jetski with 400 hours is old and beat a yamaha with 400 is just broken in.

hope this helps

Evan

[Fast Fred]

on the 20" shaft, run it deep the hulls a dog, a vary slow one, set at racin hight the hull rolls over at speed when ya turn it. these are the issues with this setup.
it's been tryed.:eek: issues with a 15" Moda, NONE:eek: :cool:
hey Burg whatsup:cool:

[ricklem]

Thanks fellas. It's making more sense now. Of course the more I'm learning the more I'm aware of vast areas of ignorance that I know nothing about. It would sure be nice to be able to see all of these boats, motor set-ups, etc. Maybe I'll be able to attend some races someday. Looks like Michigan is the closest to me.

It's good to hear the stock outboards are not as high strung or stretched to the limit like the PWC engines are. I could have bought a new boat for what I've thrown at fixing mine. I also have racked up almost 750 hrs since 1999. And thats with it sitting out late summer and fall a couple of years.

Thanks again for the advice guys.

[fountain35]

i think you will love your Dux, but do a short shaft.
i tried a bunch of chit and 5 in dont seem like much but on these boats 1/2 in makes a big diff.. and having it that high off the transome you would need a jack plate and who knows what to make it work,, instead
evan has some stock yam 50's i would look at,.
or get a tldi tohat 40. 50 not avail yet with tiller.
or merc 60 but seem awfull heavy././ ask re merc these guys will know.
yam 50 light fast snappy & put a power tech 17 pitch prop 3 blade semi cleaver and for all around romping around its great.
If u gonna race then its a diff ballgame. then u need a snorting hot rod motor with steering damper , bungee set up with hours and dollars in proping testing and getting it to run on the ragged edge and getting seat time to be comfortable running it, just like any racing it takes commitment time and $ to be competitive,
but do top o mich,
got a group from the west coast for the top o mich this yr,, we are going to go have fun and meet all the folks and learn,,, as hoping to get it going here,
we are bringing our 3 legged dogs with basic motors,, ; )
so far i have commits from 3 boats. i need to get it up to 6 as i know 1/2 will fall out,, people always do...
pick brains on set up etc as its amazing how touchy these little boats are..

jonas

[berg969]

speaking of motors i am at the miami boat show and i spoke to the tohatsu guys and starting july there will be 50hp 15" tldi epa approoved motors for sale.

[ricklem]

Hi guys,

Nice to hear a kind word on those 3 legged dogs. Glad to hear Tohatsu may have a 50hp 15" tiller for sale soon, also. I have checked the websites for Yamaha, Merc, Suzuki, Honda, Evinrude...did I miss anyone?? for 15 " shafts I have only found a Tohatsu and Merc 40 hp, for sale now. Where are these NEW Yamahas you are talking about?? I am not a mechanic and need something with a warranty and as idiot proof as possible. I'd like to have it EPA aproved also.

One of the very first videos I saw of these SLTs was off the Sea Wolf website and featured a race with these boats running Honda 45 hp engines. I'm guessing they were 20 inch shaft motors, maybe not.

Being in Iowa, Outboard motor dealers are few and far between. Plus all of the ones i've talked to cannot understand the appeal of this type of boat and are not real positive of their existence. ( I haven't ever actually seen one myself)

It's great to get these tips, because I have zero experience so far. Thank you.

[Fast Fred]

Yama 50hp short at the Dealers this season, the TLDI 50hp short manual braket
works nice. ThunderDuck got a Hotsu Screamer w/tiller 1500$$ thats a good deal :cool:

[ROLF]

Do any of these manufacturers offer 90Hp short shaft motors?
Rolf

[Fast Fred]

Yamaha, but i don't think thay offer it, but you can make one, The Burgs got one:eek: :cool:

[berg969]

here is a pic
http://img111.imageshack.us/img111/2060/2c794kx.jpg
http://img111.imageshack.us/img111/6870/c91e7ih.jpg
http://img51.imageshack.us/img51/3622/e9c65nv.jpg

[ROLF]

Berg sent you a pm. Rolf

[Liquid Force]

Berg,

Is that a normal 90hp with a chopped mid or a 90 powerhead on a 50 mid section? (looks like it used to have power trim and tilt) can you give me some idea on the recipe for that setup and how it performs, I have an old Gemini ZX1 sitting in the garage that I wouldn't mind sticking something stupid on... Tired of running stock 50hp yammy's want something thats got to run 70mph and maybe give 80 a nudge... Doesn't need to legal for any class only for scaring the $hit out of myself...

[Fast Fred]

all stock parts but for the drive shaft:cool:

[berg969]

like freddy said its just a combination of stock parts except the drive shaft. unless you have accses to a junkyard of old yamahas it will be a very expensive motor.

[Fast Fred]

at 80mph the hull becomes vary vary light ( no mater wich one) :eek: