$txt['youtube'] = 'YouTube'; $txt['youtube_invalid'] = '#Invalid YouTube Link#'; Experimental 2.0 Stomp-grate

Author Topic: Experimental 2.0 Stomp-grate  (Read 1263 times)

0 Members and 1 Guest are viewing this topic.

Offline bizler

  • Mokai Addict Member
  • *****
  • Posts: 596
  • Age: 77
  • Location: Vancouver, WA
  • Cool Points: 50
  • Engine: EX21 W/EX17 Head
  • Model Year: 2010
Re: Experimental 2.0 Stomp-grate
« Reply #15 on: July 08, 2020, 12:50:20 PM »
Wow, Bill.  That is just beautiful.  You and Troy are a great team

Thanks, Hillbilly.  This project has been a Godsend in these times of isolation.  I enjoy making chips in my shop as much, or possibly more, than my Mokai itself.   ;)   Bill

Offline Duff

  • Jr. Member
  • **
  • Posts: 81
  • Age: 71
  • Location: SE PA
  • Cool Points: 10
  • Engine: Tom's EX21 Upgrade
  • Model Year: 2002
Re: Experimental 2.0 Stomp-grate
« Reply #16 on: July 08, 2020, 09:49:35 PM »
Is there a stomp grate available for my Old 1.0 2002 ?

Offline Painlesstom

  • Painless Tom
  • Administrator
  • Mokai Maniac Member
  • *******
  • Posts: 6250
  • Age: 45
  • Location: Georgia
  • Cool Points: 65
  • Making Your Mokai... A Better Mokai!
    • Painless Products
  • Engine: 2 EX21/17 / 1 KX21
  • Model Year: 2003 / 2011 / 2015
Re: Experimental 2.0 Stomp-grate
« Reply #17 on: July 08, 2020, 09:57:31 PM »
I've made stomp grates for the one piece models, it's been a few years since I've made one though. My grate has wider openings and lets more stuff pass through, so using it in rocky bottom rivers isn't a good idea. Best suited for the leaves, sticks, softer type of debris. I can still make them though, email if interested. painlesstom@improvingyourmokai.com
Tom

  >:D    

_________________________

www.PainlessClutch.com

Offline msfitoyfactory

  • Newbie
  • *
  • Posts: 18
  • Age: 61
  • Location: north carolina
  • Cool Points: 2
  • Engine: 9.5 hp
  • Model Year: 2020
Re: Experimental 2.0 Stomp-grate
« Reply #18 on: September 15, 2020, 02:30:28 PM »
Pardon my ignorance but what is a stump grate?

Offline Mr. Murphy's Law

  • Jr. Member
  • **
  • Posts: 23
  • Location: South Carolina
  • Cool Points: 4
  • If I have to explain the UN, you'd not understand
Re: Experimental 2.0 Stomp-grate
« Reply #19 on: September 15, 2020, 04:42:26 PM »
I have been working on a stomp grate unit for the Mokai 2.0.  I have what I think is a workable accessory that I would like to provide to another owner for testing since I do not have a 2.0.  This accessory replaces the original equipment grate with an articulated one that is controlled via a cable and lever assembly in the cockpit, either under the gunwale or on top of it.  mokaidreamin, Troy, has installed one of these units on his Mokai and his initial feedback with the installation is positive. He hasn't yet, to my knowledge, tested it in typical conditions with leaves and debris.  If you are interested please get in touch via IM or email.  I do not intend on mass producing these units but I will attempt to build a few and/or share my design if there is interest. Machining for me is a hobby, not a business.

bizler, love the pic of the "transition" drive in pic #2 !!!....I've been curious as to how they achieved the transverse engine in the 2.0

I'd guess at that size its a 1:1 ratio ?  be neat to know and then machine/fab one at 1:2 or 3 just to see how it would perform 
I hide in the shadows, I hide in the Light ...and just when you think everything is going fine...I LEAP out and strike !!!

Offline Mr. Murphy's Law

  • Jr. Member
  • **
  • Posts: 23
  • Location: South Carolina
  • Cool Points: 4
  • If I have to explain the UN, you'd not understand
Re: Experimental 2.0 Stomp-grate
« Reply #20 on: September 15, 2020, 04:46:08 PM »
Pardon my ignorance but what is a stump grate?

"Stomp" cause if I'm not mistaken Tom made one that was foot operated ....but its a mod to the intake gate on the pump(jet) to clear leaves, sticks etc without getting out of the boat...the intake on these little boats are tiny to begin with so any obstruction will drastically affect performance
I hide in the shadows, I hide in the Light ...and just when you think everything is going fine...I LEAP out and strike !!!

Offline Mokai Dreamin'

  • Mokai Hero Member
  • ****
  • Posts: 325
  • Age: 59
  • Location: Alaska
  • Cool Points: 29
  • Engine: Kohler
  • Model Year: 2019 ES-Kape 2.0
Re: Experimental 2.0 Stomp-grate
« Reply #21 on: September 15, 2020, 05:52:07 PM »
bizler, love the pic of the "transition" drive in pic #2 !!!....I've been curious as to how they achieved the transverse engine in the 2.0

I'd guess at that size its a 1:1 ratio ?  be neat to know and then machine/fab one at 1:2 or 3 just to see how it would perform
Those are actually my photographs. This is the overdrive that Mokai developed for the 2.0. Originally they started out with a 3.1" diameter pulley on the engine that went to a 2.6" diameter pulley on the overdrive, but engine did not have enough torque and horsepower for that ratio. They've since gone with a 2.9 inch to a 2.8 inch, so there's a little bit of a ratio there, but not much.

In use, it takes about a quarter-mile to actually gain the extra speed or otherwise take advantage of the overdrive.  I explained this to other people as imagining your car being in third gear to start. It puts a whole lot of strain on the engine initially, but assuming you're on flat ground and don't encounter too much resistance, the engine will eventually come up to speed, and things will become a whole lot easier as the engine breathes a sigh of relief. You'll also gain some extra speed.

That's essentially what's going on here. There is however no transmission to switch gears. So, with that said if you're less than say 200 pounds and on fairly flat water you will really see the advantage of the overdrive, and this boat can really fly. I've had it up to 21 miles an hour, and I'm in the low 200's for weight. People in the 150 range can get this thing up to 24+ mph.

Now, go the other direction, and say your 215 pounds and running against some currents or upstream. You may not get more than 7 miles an hour, so that's the range.
Best,
Troy

Offline Painlesstom

  • Painless Tom
  • Administrator
  • Mokai Maniac Member
  • *******
  • Posts: 6250
  • Age: 45
  • Location: Georgia
  • Cool Points: 65
  • Making Your Mokai... A Better Mokai!
    • Painless Products
  • Engine: 2 EX21/17 / 1 KX21
  • Model Year: 2003 / 2011 / 2015
Re: Experimental 2.0 Stomp-grate
« Reply #22 on: September 15, 2020, 09:35:50 PM »
Very well explained Troy, thanks for helping everyone understand that.  \./8
Tom

  >:D    

_________________________

www.PainlessClutch.com

Offline msfitoyfactory

  • Newbie
  • *
  • Posts: 18
  • Age: 61
  • Location: north carolina
  • Cool Points: 2
  • Engine: 9.5 hp
  • Model Year: 2020
Re: Experimental 2.0 Stomp-grate
« Reply #23 on: September 15, 2020, 09:51:08 PM »
"Stomp" cause if I'm not mistaken Tom made one that was foot operated ....but its a mod to the intake gate on the pump(jet) to clear leaves, sticks etc without getting out of the boat...the intake on these little boats are tiny to begin with so any obstruction will drastically affect performance
Oh I get it now...thanks!

Offline Painlesstom

  • Painless Tom
  • Administrator
  • Mokai Maniac Member
  • *******
  • Posts: 6250
  • Age: 45
  • Location: Georgia
  • Cool Points: 65
  • Making Your Mokai... A Better Mokai!
    • Painless Products
  • Engine: 2 EX21/17 / 1 KX21
  • Model Year: 2003 / 2011 / 2015
Re: Experimental 2.0 Stomp-grate
« Reply #24 on: September 15, 2020, 11:17:11 PM »
The term "stomp grate" goes back long before anything I've done, and nothing I've made has been foot actuated anyhow. It's just a generic terminology for the articulating grate because that's how they originally operated on real jet boats. Spring loaded grate had lever that came up the back of the transom onto the swim deck area that one could throw a leg over and stomp on the lever/grate.
 ;)
Tom

  >:D    

_________________________

www.PainlessClutch.com

Offline msfitoyfactory

  • Newbie
  • *
  • Posts: 18
  • Age: 61
  • Location: north carolina
  • Cool Points: 2
  • Engine: 9.5 hp
  • Model Year: 2020
Re: Experimental 2.0 Stomp-grate
« Reply #25 on: September 16, 2020, 09:02:02 AM »
The term "stomp grate" goes back long before anything I've done, and nothing I've made has been foot actuated anyhow. It's just a generic terminology for the articulating grate because that's how they originally operated on real jet boats. Spring loaded grate had lever that came up the back of the transom onto the swim deck area that one could throw a leg over and stomp on the lever/grate.
 ;)
Cool...looking forward to a 2.0 version  ;)

Offline bizler

  • Mokai Addict Member
  • *****
  • Posts: 596
  • Age: 77
  • Location: Vancouver, WA
  • Cool Points: 50
  • Engine: EX21 W/EX17 Head
  • Model Year: 2010
Re: Experimental 2.0 Stomp-grate
« Reply #26 on: September 16, 2020, 11:35:10 AM »
Misfittoyfactory, If you start at the beginning of this thread you will learn that I have fabricated two versions for the 2.0 and provided them to Troy in Alaska. His response was mixed. While they fit and operated satisfactorily, it was uncertain that they might be a cause for the varied performance he experienced with his Mokai. Last I heard from him was that he was going to remove the actuating cable sleeve and nut from the intake tunnel, plug the hole wit a carriage bolt and use the stock (modified) grate to see if it had a positive affect.  I modified his stock grate by radiusing the intake side all around.

Apparently, these last actions did not show any distinct improvement. His latest comments indicate that he is still experiencing mixed results depending on weight and water conditions and odd Tuesdays  ;) .

It was not my intention to go into production with the 2.0 grates as I am just a hobby machinist.  I do not have a 2.0 so I am unable to verify the functionality on my own. I can, and am willing, to build them by request.   Bill

Offline Painlesstom

  • Painless Tom
  • Administrator
  • Mokai Maniac Member
  • *******
  • Posts: 6250
  • Age: 45
  • Location: Georgia
  • Cool Points: 65
  • Making Your Mokai... A Better Mokai!
    • Painless Products
  • Engine: 2 EX21/17 / 1 KX21
  • Model Year: 2003 / 2011 / 2015
Re: Experimental 2.0 Stomp-grate
« Reply #27 on: September 16, 2020, 04:51:23 PM »
Cool...looking forward to a 2.0 version  ;)

Bizler is the man to talk to there, I don't have any plans to get too involved with the 2.0. If I ever do it will be years down the road when they are being sold used for cheap. I'm patient.  :D
Tom

  >:D    

_________________________

www.PainlessClutch.com

Offline Mokai Dreamin'

  • Mokai Hero Member
  • ****
  • Posts: 325
  • Age: 59
  • Location: Alaska
  • Cool Points: 29
  • Engine: Kohler
  • Model Year: 2019 ES-Kape 2.0
Re: Experimental 2.0 Stomp-grate
« Reply #28 on: September 19, 2020, 09:55:44 PM »
I just wanted to do a short update as my latest conversation with Bill via personal emails seem to suggest he thought his latest design was not a success.

So I'm here to say that is not the case! Bill's latest iteration of the design is a success, and will work well for the larger debris, grasses, and if any pebbles get lodged in between the tines. Best I can tell it does not effect speed or if it does, it's very minor.

Unfortunately it can't do anything to prevent things like small sticks getting into the impeller, but that is certainly not a flaw of his design. The large number of blades on the impeller seem to cause a lot more things to get stuck in it versus something like a jet ski impeller design.

I also want to mention that I'm one of the few people who has a clutch for the 2.0, and while it's not absolutely essential for the stomp grate to work, it certainly is much more convenient. Anyone else would have to shut off the engine, operate the stomp grate, and then restart.

I can also say a lot of times just going to neutral and allowing water to flow over the grate (rocking helps) can do wonders to get rid of debris.  If you can combine current with the stomp grate, so much the better!

And on this particular version of the stomp grate it opens towards the rear of the boat so encourages things to slide off much more easily. In that sense I think it superior to earlier versions, and it also offers better protection against hitting something if you happen to accidentally leave it down.

I think the only thing that could make this better would be material selection. Something made out of stainless steel versus aluminum would certainly be more durable, but Bill does not have the capability to do welding. I can also say that if things are not smooth you can really create extra cavitation too, so the aluminum may actually be better in that regard.

Round tines vs square ones also allow for better water flow, and Bill took the time to round over some of the edges. The only thing that I'm going to change is reducing the thickness of the lock nut that secures the cable to the hull, and then round some of the edges to further reduce cavitation and improve water flow.

Overall Bill's work is top-notch, and such a treat to have somebody so talented contributing to making these boats better. So thanks once again Bill for all your efforts! You did a beautiful job, and I am certainly most appreciative!
Best,
Troy