Diamond Dave

I had a dream where I had two Ford 9" spooled drop outs that would fit in my outdrives (one in the top and one in the bottom) and they never blew up no matter how bad I thrashed them.... seemed legit lol

BUP

iTrader: (9)

Have alot to write here as the trip was a full education that was well worth the time. If you think you know alot about gears and gear manufacturing, I have about a 100 of the world experts that will say sorry to you as there is alot more to it than what you think and you have alot to learn. Also size of the gears does matter but not really either depending on what and how it is made along with materials.

The jist

Near net forged gears are NOT the best for high loads and shock loads,

next - what stock was used to manu the gears ?

What is the true quality of the gears ?

Was the right materials and manu process used for the application and its conditions ?

What are internal temps and do they vary alot thru out running conditions ?

What heat treating process was used and was it done correctly ?

What is the support structure for the internal components ?

Are the gears shot peened ?

Was the installation and all tolerances correct and maintained correctly ?

Is the tolerances all uniform from gears after they are manu ?

And a bunch more questions need to be answered

Anyways I left the gears with a USA manu to X-ray, dissect and examine them fully as they will stripe layer by layer to see what and the quality is to begin with.

I have other areas of this who want new gears and failed gears sent so they can examine them as well..

Also I received 3 names who I should contact and of course a consultant fee will be charged to see what can be done even going down the road with new design & gear manufacturing components.

More info to come when I get the Metal Science report back. Yes they like to call it that also.

mike tkach

iTrader: (3)

i believe the size of the gear is a big part of the problem with the bravo style gears.it is a ring&pinion gear so compare it to a ford 9 inch and and it starts to make sense.the upper gears in a b max or imco scx are quite a bit larger than the merc bravo gears.imo,no gear oil can fix a poorly designed gear set.i also believe that their is a lot of flexing with the gear case and that does not help either.

buck35

Is it that poor of a design, there are tens of thousands of them running trouble free, now if you run more power through it than it was designed for and it breaks, damn that sucks. The biggest problem seems to be that the upgrade to reliability costs as much as many boats.

articfriends

iTrader: (1)

Me and bob madera sent lowers out and had them disected for stock hardness, case harness thickness, base material, tried dlc coating, addtl hardening, cryo iso rem and different oils. In the end it was going to be 5000$ for 1 test set of lower gears that may or may not have been better than stock and it got too expensive for ROI so we settled on cryo iso rem with amsoil with additive pkg which doubled life of lower gesrs behind 1000+hp, call me at 989 two one three 7434 when you have time and i will share all the info we garnered and im sure bob would pass on what he found on his end, smitty
The upper gears were so complex we never got anywhere with them as far as having them built but the other "smitty" has been working on it, smitty

thirdchildhood

iTrader: (6)

They are not trouble free in high performance or offshore conditions. I thought the lower gears were pretty much bulletproof but now I hear that I was lucky to get 200 hours out of them. How often does a car or truck rear (or front) ring and pinion gear set fail? Almost never. It is definitely not a maintenance item on a high performance car or truck. Even the gear oil seems to last forever. Yes, the high end drives are $30,000+ and the jury is still out as to whether the gear sets will last any longer than Mercury gears. Very small gears doing an awful lot of work. It'll be interesting to see what the engineers come up with for BUP.

buck35

I agree with what you are saying, but then again I don't jump my car or truck... Well at least not on purpose. Also believe merc could charge half and still have a tidy profit

donzi matt

iTrader: (1)

Wheel hop a 500 horsepower car at the track and see how long the rear end lasts. Hell we broke a Winters quick change rear end last year at about 480 horsepower racing on ice.

BUP

iTrader: (9)

No matter who I talked to - there is 2 guys names that came up for anytime there is a problem or how to address anything with gears no matter of the app.

I looked at the one guys client list as many were from Aerospace to NASCAR to NASA to F1 to anything and everything that deals with gears. His list starts from 1976 to current. But here is the kicker - ONLY ONE MARINE manu ever used his his services way back in years and that was OMC. Anyways another company said all it takes is money and each gear would be an estimate cost of around 1500 bucks and then redesign the support structure. That would cost alot but there is someothers willing to work with me and I did make some new contacts that will help.

How far do I want to go with this ? I do not know as of yet but I would go on for a long time if the money was there. No easy to do by myself. I might look into an investor or a investor group to help with something plus hopefully use a trump card if a company will give out alot free time. Also I do not want to throw out every comment up here either as to some of the stuff that was talked about. just saying. Many questions still needing answers. Its a start.

I will say this, many years ago bravo's had less problems than they do today. Yes hp increases are more into the mix but keep mind so is modern technology and the way to study / examine just about anything currently to come up with better solutions.

Also did you know the standard Bravo is only rated up to 400 hp the Bravo X only up to 450 hp and the XR up to 600 hp... granted I do not see much over 700 hp but I do know this many and I mean many hp 525 end users really are not getting more than 300 hrs out there Bravo's XR's and some only 250 hour mark. And it is NOT because lack of maintenance nor running them extremely hard. I have pulled many of the hours and running rpm times from the PCM / ECM just to see and looked for any over speeds faults as well. .

Also I actually have the same company who is looking at the gears that wants a brand new Bravo drive and of course a used one to completely examine them, I can provide / donate a complete used Bravo drive but sure in hell can NOT donate a brand new one. Anyone ? see where I am going with this - it all reverts back to money like everything.

So far this has been a fun project and i learned a whole lot plus worth my time along with the new contacts that were made. We will see what takes place.

BUP

iTrader: (9)

With throw this out as some of the indepth they talked to me about was F1 tech and oils being used and gear manu using NANO technology..

There really is nothing big inside an F1 tranny - actually alot smaller than you think and they have to last for 6 races. Maybe a cool vid for some plus they bring up the NANO tech as well.

https://www.youtube.com/watch?v=rUCapV3p2J4