Unusual RIB - Opinions

[Limecc]

Sorry Guy you'll have to dumb it down for me. Nearer the surface you get still less grip - At 8 knots the prop's already spinning just 700rpm short of max rpm.

If it wasn't I get it. Similar reason why Turning Point introduce exhaust gas over the blades to induce slip and get the engine up to higher rpm's earlier at low (displacement) speed.

We don't know the pitch but the gearing's the same (top gear = 1.4:1).

[GuyC]

I found the spec for a ZF 300 two speed transmission and the low gear ratio is 1:1.483 and the high gear is 1:1.161. It's the 1:1.161 ratio that the boat is missing.

If you were to swap the ratio for a 1:1.161 gear, I guess it would simply bog down.

Maybe speak to the seller and ask if they would fund or partially fund a new two speed gearbox.

[Limecc]

Makes sense.

But if it's fixed in first gear then why so slow to plane?

[GuyC]

I guess they aren't meant to operate when entirely submerged or at low speeds and it requires judicious use of the throttle and trim tabs to get it out of the hole.

[beamishken]

Theres a choice of ratios of the 2 speed boxes, whos to say the current box is the same ratio as either 1st or 2nd?
Simple answer is its got the wrong box, you can theorise & prop calc all you want but without the 2 speed box behind that old school mechanical engine its never going to perform properly.



Sent from my SM-G950F using RIB Net mobile app

[Pete7]

Originally Posted by GuyC

I guess they aren't meant to operate when entirely submerged or at low speeds and it requires judicious use of the throttle and trim tabs to get it out of the hole.

That surface drive is for race boats and will be a dog on a leisure rib. Time to walk away or fund its replacement with a duo prop stern drive but that is big bucks.

[Limecc]

Originally Posted by Pete7

That surface drive is for race boats and will be a dog on a leisure rib. Time to walk away or fund its replacement with a duo prop stern drive but that is big bucks.

Imagine and then the ECU goes. Bummer

[beamishken]

Originally Posted by Limecc

Imagine and then the ECU goes. Bummer

There isnt an ecu on a tamd 63 its a mechanical pump engine

And no one built a sterndrive to run behind a 63p full repower or refit the correct 2 speed gearbox

Sent from my SM-G950F using RIB Net mobile app

[Dry Run]

This boat was Dry Stacked with my yard for about 5 years (with current owner). The guy is a diver and works away from home a lot (hence the low useage). He always seemed genuine enough, but I don't think he's that experienced with that boat. If the OP is still interested or wants any mor info about it's history, then PM me. Regards

Steve

[ShadowDiver]

Have you considered the question of compliance? 2006 and no HIN Number, alarm bells straight away. The boat should be CE marked, have a European Declaration of Conformity and a HIN number to be legal to use as a leisure boat.

If not, and you have an accident, will your insurance company pay out. Will you even be able to insure it without a HIN number? Sounds like the boat needs Post Construction Assessment from an Approved Body so you must factor in another £2500 plus VAT.

[Limecc]

Scare post alert.

Good job we left the EU. Too many self-serving bureaucrats interfering needlessly. Too bad all those self-builds can't get insurance. Maybe they would if fitted with a CE (China Export) sticker.

[69cmw]

Getting a number made up isn’t an issue if you know where to look [emoji848]

[Pikey Dave]

Originally Posted by 69cmw

Getting a number made up isn’t an issue if you know where to look [emoji848]

Yup! and plenty of RIBs out there that were made before HIN numbers/RCD/CE marks were introduced.

[beerbelly]

Originally Posted by Pikey Dave

Yup! and plenty of RIBs out there that were made before HIN numbers/RCD/CE marks were introduced.

plenty of ribs out there made after HIN marks were introduced with no HIN