searafting.no

We are having big problems with our Xr drives and they seems to last 100-150 hours before the top gears brake a tooth, as we run a charter bussines and need the boat to be operativ most of the time we are now in the search for stronger drives. We run 2 x Yanmar 315 hp diesel engines true bravo one XR I.T.S drives 1,5 ratio.

We are considering to buy B-max drives, but they only come in 1,3 ratio and we then have to go down in pitch to compensate, we are now running a Bravo one 28 lab prop and the engine rpm is 3950 and the top speed is 55 mph

I have been told that if we need to go down i pitch to compensate for lower ratio we will losse speed because of more prop drag.

If some one have some experience on the subject and maybe some idea on how many mph i would losse i would love to hear from you all.

We are willing to losse some top speed for better reability as we need the boat running and making money.

Regards frustrated rib charter bussines in Norway.

GOODT

the xr should handle the 315 diesel with no problems normally only one or two broken teeth indicate impact damage or launch

searafting.no

Thanks for answare, the boat that the Xr drives are mounted on is 36 feet rigid Inflatable boat that carry 18 people out in big waves and jumping around and yes the props are often out of the water.

There are 3 boats of the same brand and with the same set up, the 3 boats have now broken 9 xr top gears and its always the upper gear (nearest the top cap) that is the problem. we are searching for stronger drives and the B-max is as you know the only direct replacement for the bravo drive.

We are also looking at Arneson ASD 6, but we are concerned about the acceleration with Surface drives, and how it will work driving in big waves (5-8 feet or more) in speeds down to 18-25 mph the boat is still in plane at 15 mph

GOODT

if they are comming out of the water like that the only thing that will even come close to holding up would be surface drives, that a hell of a shock when they come back in and unless you have a throttle man that knows what he is doing your going to be breaking anything you put on there

Rik

There will be no acceleration problems with the Arneson Surface Drives.

In fact, it will have better acceleration than you alternatives.

Rik

Payton

Plus you'd have a way cool roostertail to show off with.

Iggy

www.konradmarine.com

If our Navy, Marines, and Coast Guard can't break them, I bet you can't either.

Rik

Our Navy and the Navy's around the World use Arneson Surface Drives more so.

Of course Mercury has the largest presence in the Military market with the outboards but we are happy to be second to them in the number of military applications.

customryder

asd 6 with light throttle