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View Full Version : Low Top Speed

Double Overhead
07-16-2005, 12:55 PM
Yesterday I took the S&S out with the family. I hardly ever run it hard because we are always wakeboarding at about 20mph. I opened it up and the fastest it would go was about 37 at around 3600 rpm. Its been so long since I have run it like this so I dont remember if it went any faster in the past. Does this seem slow? I had 3 adults and three children with me. I dont know much about my prop other than its a 3 blade. Boat runs great otherwise.
6ballsisall
07-16-2005, 12:57 PM
That might be a little slow but you are loaded down with people. Wouldn't hurt to look at those points if you still have them and check the cap and rotor for wear and corrosion. Your RPM's do seem weak though. Did you have any ballast in the boat as well?
ssippiriverrat
07-16-2005, 02:58 PM
I have a '79 too and I don't think that is that slow, try running it without people -- I usually wakeboard too so I don't open it up that much but mine never goes above 40 even without weight.

Just another note--I recently put a 4 fin prop on--wow--it holds 22 mph when you are wakeboarding so much better--with the 3 fin you need to consistantly adjust it.
ssippiriverrat
08-17-2005, 10:59 PM
Ok my bad, check that, I open her up last weekend with no weight and two people in the boat and she got about 45-50 depending on which gauge is working the best. She really can still move!

And she is older than I am--damn!
mcprostar197
08-17-2005, 11:07 PM
Is 44 a slow top speed in our 197 with just me in it?
ski_king
08-17-2005, 11:08 PM
YOu should be able to get around 45 mph at 4500 rpm with 3 in it, maybe down to 42 with the load. Mine will do 43 pulling a barefooter and 2 in the boat,
6ballsisall
08-17-2005, 11:11 PM
Is 44 a slow top speed in our 197 with just me in it?


I think thats about average on the newer boats like the 197
ski_king
08-17-2005, 11:12 PM
Is 44 a slow top speed in our 197 with just me in it?
Acording to Waterski Magazine (http://www.waterskimag.com/product.jsp?ID=68451&product=boat&clientID=17146) 43 is top speed for a 2005 197.
Leroy
08-17-2005, 11:13 PM
Double Overhead; your speed and RPM's seem correct. I'm not sure what to expect for WOT RPM's from a boat that old.


MCPS197; From what I hear mid 40's is pretty typical for most of the MC's. Calibration can play a big role in what you read, check with GPS.
mcprostar197
08-17-2005, 11:15 PM
Why are the older boats faster than the newer boats? That doesnt make much sense to me...
ski_king
08-17-2005, 11:17 PM
Why are the older boats faster than the newer boats? That doesnt make much sense to me...
up to about 86, the boat was smaller and weighed 2200 soaking wet.

But still, they only had 240 HP.
Leroy
08-17-2005, 11:25 PM
MCPS197; What data do you base this on?



Why are the older boats faster than the newer boats? That doesnt make much sense to me...
6ballsisall
08-17-2005, 11:26 PM
Why are the older boats faster than the newer boats? That doesnt make much sense to me...

Smaller boat, less wetted surface=less drag. They weighed quite a bit less too.

I'd still take the wake of my 86' over a new 197 until you get shortline. The spray is a bugger
PendO
08-17-2005, 11:35 PM
Just a hypothesis ... the older boats had less boat in the water ... for example, the new PS 197 might have more surface area that gets wet, spreading out the wake, making the wake smaller, but also creating more drag on the boat ...
PendO
08-17-2005, 11:37 PM
Smaller boat, less wetted surface=less drag. They weighed quite a bit less too.

I'd still take the wake of my 86' over a new 197 until you get shortline. The spray is a bugger

yeah yeah, what he said;)

wasy typing my response, to prev. post, posted and saw you had said the same thing (as I was typing) you win;)
6ballsisall
08-17-2005, 11:37 PM
Just a hypothesis ... the older boats had less boat in the water ... for example, the new PS 197 might have more surface area that gets wet, spreading out the wake, making the wake smaller, but also creating more drag on the boat ...

Good hypothesis and pretty much right on track. However, nothing tops the wake (or lack there of ) from a 83-86 hull MC Skier 19/S&S The spray, well..........thats a whole nother issue best suited for the 197
SKI*MC
08-18-2005, 12:10 AM
ok same thing happened with us, convert to electronic ignition, it will make a world of a difference.
mcprostar197
08-18-2005, 03:15 AM
MCPS197; What data do you base this on?

I base it on what sippiriverrat said on the first page about his boat, which is older.
PeteS
08-18-2005, 08:53 AM
Yesterday I took the S&S out with the family. I hardly ever run it hard because we are always wakeboarding at about 20mph. I opened it up and the fastest it would go was about 37 at around 3600 rpm. Its been so long since I have run it like this so I dont remember if it went any faster in the past. Does this seem slow? I had 3 adults and three children with me. I dont know much about my prop other than its a 3 blade. Boat runs great otherwise.
For DO, I experienced the similiar thing on my '88. I completed the following for different reasons, and my top speed jumped up 45 MPH:

1. New coil, wires, plugs, and electronic ignition.
2. Carb rebuild.
3. Replaced ALL fuel filters.
4. Replaced PCV valve.
5. Adjusted timing.

Like I said, all of the items needed completion, so I'm not sure which was the most effective in the top speed, but it runs great now. Hope that helps.