Yamaha gears, need better ratio

[Raker25"]

I´m trying to figure out my alternatives here, please help me out..:confused:

I have a Vmax 150 -98 carb with the 14:28 gear ratio. Problem is the prop-selection.. Can´t run small-hubs because of prop-ride tendensies and high pitch isn´t that good for this either.. Been there, done that...
I´m overreving quite a lot with a Raker28" and really want to keep that one since it works very nice on my boat, running about 82mph with it and with nice handling.
Have an opportunity to buy a really nice lab finnished 26" Hydromotive cleaver which is told to work extremely well on my boat in rough seas. But as you can understand this just won´t do with my gears.:(

Therefor my question. The 14:26 ratio is "bolt on" as I understand, but what about the preferable 16:29 and 16:28 gears (3,3L)? I´m into that I just will switch the gears and keep my housing since it´s in good shape and has the Bobs nosecone with water intake. Will those 3,3L gears be an alternative or don´t they fit my lower at all?

With the 14:26 the Raker would do fine I think but the 26" Hydromotive would still be a bit small.
BTW is it a "doable job" to switch gears or is it hard to make it right?

Has anyone with knowledge had the energy to read this far of my mumbo jumbo, please enlight me with some good advise! Thanks!

[Dave S]

Ya sound like Ya doening good, good speed . But what boat? In my low oppion ya need to Cup it a bit more. And ya can do that on the Leading Edge.;) Most do on traileing edge.:confused: :D ;) I hope the Prop Gods Woun't strike me.:eek: If ya can't switch gears add omphff.;)

[Raker25"]

Thanks!
Boat is a 18 foot Kevlar hull, Hydrolift R18.
Don´t think modding prop will do, wants to to lower my rpms 5-600 with the 28"...

[Ray Neudecker]

There are several gear ratios available from a 1.73, 1.80 and 1.86 for the 2.6 liter engine. The 3.1 liter gears will not interchange.
Ratio changes are possible if done by a competent shop with the proper alignment tools.
What RPM's are you turning? That engine will turn 6400-6800 happily.

[Raker25"]

That engine will turn 6400-6800 happily.
It sure does.. Really nice to know, I also put 1% additional oil to the gas. Turning about 6500+ at maximum speed with the 28".
Just have to find me anouther bigger rough-sea prop then, seems a bit overkill to change the ratio.

THANKS!

[Dave S]

Nice boat.:) I think you shoul try some other props. Here you can use someones prop that don't work on his boat but will on yours. But I bet you don't have a lot of hot boats in sweden?:confused:

[Raker25"]

I´m afraid you´re right about it´s a limited playground over here, but have managed to test some steel though. Have tried 7 diffrent props so far both 3 and 4 blades, Mach Sterncleaver 26" gave best handling and good speed. Prop was far to small though and those aint made any longer so its hard to find'em.:( The Raker 28" and a Mazco 32" smal hub cleaver has been fastest but the Mazco gave me an evil prop-ride which turned the boat 90° and threw my passanger out... Could have ended real bad.. Won´t push that prop again, will be decoration instead.;)
Too bad the Hydrolift is rare in the states and your makes are rare over here, otherwise one could say boattype acts similar to someone you guys knew well.:(
Any nice suggestions for a fast rough-sea one which gives neutral lift or even preferable gives sternlift? 3 blades preferable, no small hubs.

Turning my thread into a propthread now, sorry guys..:D

[Ray Neudecker]

If you can borrow one, try the Yamaha Pro series 25M. It may suprise you with big end and RPM's.

[Raker25"]

Was in fact initially looking for a Pro-Series, they're said to run qiute like the Raker on mine. Bowlift, good speed and nice stable handling. Haven't tried one myself yet though. Are you sure about 25M, don´t you meen 27M?

[Ray Neudecker]

Either should work fine. I never found much difference in the performance in spite of the supposed pitch difference. The 25's are a lot easier to find here.