Searider 4.7m Engine choice

[69cmw]

I ended up with a Yam 75hp 2stroke oil injection.
A new 2 man console supplied and fitted by Whitham glass fibre with a 91 litre fuel tank fibre glassed in place.

The engine I offset 2 inches and lifted it up 2 holes, there is no chine walking and it does a GPS verified 44mph with stainless prop.

[Kat1nka]

Hi,

as a new member to the forum and an new owner of my first Searider which I am slowly sorting out I wonder about the engine offset. I guess it is to counteract the propeller rotation ? How do I calculate the offset ?
The previous owner has installed the engine in the dead middle and I get a fair amount of chinewalk at full throttle. Standard aluminum 21 inch gives 42 - 43 knots, SS 19 Ballistic 41 + knots but I think I need to raise the engine with the Ballistic ?
The boat is a 4.7 SR with a Yamaha 90 AETOL, and yes I know it is at the upper limit of approved power .

[peterwhite]

Very general rule of thumb is 1.5" per 100hp offset to starboard for rh prop. Depends on speed hull and prop etc. hope this helps

[Kat1nka]

Thanks !

[Downhilldai]

Originally Posted by Kat1nka

The boat is a 4.7 SR with a Yamaha 90 AETOL, and yes I know it is nearly 30% over the upper limit of approved power .

Fixed

[Rogue Wave]

did you beaf up the transom or support struts?

[Kat1nka]

No beefing up (yet). The 90 hp was already installed when I bought the boat. But I understand from other threads that it is the same transom as in the 5.4 which is rated for 90 hp. The weight is in the limits .

[Nos4r2]

Originally Posted by Kat1nka

The weight is in the limits .

The HP isn't though. Max 70hp... Your insurance might laugh if you have to claim.

[Rogue Wave]

Originally Posted by kat1nka

no beefing up (yet). The 90 hp was already installed when i bought the boat. But i understand from other threads that it is the same transom as in the 5.4 which is rated for 90 hp. The weight is in the limits .

okey dokey