440 fan cooled Suzuki motor

**chuckitt** · 07-31-2009, 07:17 AM

Hey Sandman, what is the HP of the 440 engine? I will reccomend some props when i know the HP.
Thanks, Chuck

**Sandman** · 07-31-2009, 07:38 AM

looking into it... I think it's 65 but it might be as low as 50.
I'll let you know

**Flathead** · 08-07-2009, 10:08 PM

Sandman,

I like your thinking Sandman.

Using a Snowmobile primary/secondary clutch drive train should give you 'neutral',(idle) 'first' gear (at the engine rpm's where the clutch engages until the point where the clutch no longer 'closes' and drivetrain ratio becomes fixed) and then second gear (where the engine rpm and the prop reduction would be fixed and the engine rpm is governed by the prop size and pitch.) I think such a setup would give you a great acceleration and great top end performance as well.

It also seems that such a setup would also work well with 4 stroke motors as well. I mean, we're talking about power transmission to the prop and not how the power is produced...

Just thinkin' out loud here. I've not tried it but it seems possible once you get all the details worked out....the devil is in the details.

**Sandman** · 08-08-2009, 12:02 AM

I'm a bit afraid of the idea... I'm worried about destroying an expensive prop.
I plan to do a mock up at some point to see what people think of it... I'll need to pick up some angle iron to make a good strong base to experiment from.
I have salvaged the mounting system from an old sled for the prop but I'll have to make the engine mount from scratch. It's not going to be pretty, but it's just a mock up to see if it'll work.
For now though.. my water heater died and put everything on hold for a bit.
I don't believe I'll use the chain case because it reduces the shaft speed and converts it to torque. I still need to go visit my friend about different possibilities with the clutching.

**Sandman** · 08-17-2009, 06:37 PM

Yes Flathead...
thats what I'm talkin bout!

I just worry that the drag will either burn up the belt or never engage the clutching past 1st gear...
either way.. it's just a toy to play with until I figure things out.

**Bogger2** · 08-25-2009, 10:41 PM

Hey Sandman I have A rotax 503 single carb dual ignition. I just did my maiden voyge.I have a variable pitch IVO 3 blade 62 inch prop. After cranking the pitch down on revolution I got my full 6800 rpm redline.I do have a 2.58 gear reduction on it. I got 35 mph out of my mini 11.6 boat. I will be posting some pictures of my test run later in the week under Bogger's Rotax rig. It humm's like a soeing machine.
Good luck with your 2 stroker. Mine was free from an X ultilght piolet," my IDIOT brother" after he felt he had recked enough times. It has been rebuilt since.
Bogger