User Tag List

Results 1 to 6 of 6
  1. #1
    Join Date
    Nov 2003
    Location
    Portsmouth VA
    Posts
    1,587
    Thanks (Given)
    70
    Thanks (Received)
    94
    Likes (Given)
    450
    Likes (Received)
    435
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    Chopper on a ProMax 300

    Been considering trying a big blade chopper on my Rally Sport 21 300 ProMax. Standard small shaft unit. My concerns are will the 300 likely break a blade, possibly breaking the shaft? Anyone run a chopper on a 300?
    18 Talon/2.4 carb SOLD
    26 Deck Boat/250 Merc

  2. #2
    Join Date
    Feb 2021
    Location
    las vegas
    Posts
    10
    Thanks (Given)
    4
    Thanks (Received)
    1
    Likes (Given)
    2
    Likes (Received)
    0
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by 99fxst99 View Post
    Been considering trying a big blade chopper on my Rally Sport 21 300 ProMax. Standard small shaft unit. My concerns are will the 300 likely break a blade, possibly breaking the shaft? Anyone run a chopper on a 300?
    interesting question, Mercury recommends a cleaver for the 300 hp. Mazco says (web site , looking at a 3 and 4 blade chopper) "The blades are thinned for ultimate speed, but yet thick enough for durability and are able to withstand the torque of the highest horsepower outboards." Looks like Hill Marine has choppers under 300 hp and cleavers over 300 hp. Good luck. breaking a blade at 5000 plus rpms sounds scary.

  3. Thanks 99fxst99 thanked for this post
  4. #3
    Join Date
    Jul 2006
    Location
    Wisconsin
    Posts
    5,320
    Thanks (Given)
    1000
    Thanks (Received)
    763
    Likes (Given)
    9053
    Likes (Received)
    5969
    Mentioned
    2 Post(s)
    Tagged
    0 Thread(s)
    We threw some blades at WOT on the 300PM... 4 out of 5 grenaded the brand new sportmasters and sent everything to the bottom of the lake.

  5. Thanks 99fxst99 thanked for this post
  6. #4
    Join Date
    Nov 2003
    Location
    Portsmouth VA
    Posts
    1,587
    Thanks (Given)
    70
    Thanks (Received)
    94
    Likes (Given)
    450
    Likes (Received)
    435
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by David - WI View Post
    We threw some blades at WOT on the 300PM... 4 out of 5 grenaded the brand new sportmasters and sent everything to the bottom of the lake.
    That's all I need to hear. Pretty much what I thought. I guess it goes on the shelf for now.
    18 Talon/2.4 carb SOLD
    26 Deck Boat/250 Merc

  7. #5
    Join Date
    Sep 2010
    Location
    long island,ny
    Posts
    2,412
    Thanks (Given)
    12
    Thanks (Received)
    35
    Likes (Given)
    77
    Likes (Received)
    131
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Best prop would be a Hoss HPD in a 28,29 or 30. Strong and great blade shape for take off, lift and top end. One of my best props for my 22' activator and 21' superboat with 300 merc.

    Best to convert to fat shaft however for strength as pressure on standard shaft get too high when running blades high out of water at top end.
    Last edited by dnelson964; 08-08-2021 at 05:39 PM.
    1990 22' Activator Yami HPDI 300-sold-86.4
    1976 21' Challenger 2002 3.1 Yami 250 Vmax phase lll 89.7-sold
    1982 21' Superboat 300merc-87
    1990 22' Activator yami OX66 Vmax 250-84.2
    1982 30' Scarab-twin 200 Merc-sold
    1979 21' Challenger 300 Evenrude-sold
    1979 21' Superboat 200 Merc-sold-72

  8. Likes LakeFever liked this post
  9. #6
    Join Date
    Sep 2010
    Location
    long island,ny
    Posts
    2,412
    Thanks (Given)
    12
    Thanks (Received)
    35
    Likes (Given)
    77
    Likes (Received)
    131
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Another top prop I will say best to try in standard shaft is a Spinelli DR4 29 with a touch extra cup by Tim Hoss. Was my fastest and good weight carry at high engine heights.
    1990 22' Activator Yami HPDI 300-sold-86.4
    1976 21' Challenger 2002 3.1 Yami 250 Vmax phase lll 89.7-sold
    1982 21' Superboat 300merc-87
    1990 22' Activator yami OX66 Vmax 250-84.2
    1982 30' Scarab-twin 200 Merc-sold
    1979 21' Challenger 300 Evenrude-sold
    1979 21' Superboat 200 Merc-sold-72

Similar Threads

  1. Replies: 28
    Last Post: 03-31-2018, 12:19 PM
  2. Props for sale 28 chopper , 30 chopper , 26 4 blade
    By vt200rocket in forum Propellers
    Replies: 8
    Last Post: 08-16-2017, 11:28 PM
  3. Difference between a Chopper and Chopper II prop
    By satt in forum Props, Setup, and Rigging
    Replies: 16
    Last Post: 10-13-2006, 12:37 PM
  4. Stock Chopper Verses Cut Chopper Differences??
    By RULE-1 in forum Technical Discussion
    Replies: 8
    Last Post: 09-29-2001, 02:52 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Chris Carson's Marine