Articfriends (Smitty) had dialed in a process to significantly improve the life of the XR gears in high HP/Torque motor applications back in 2007. He was also looking into a CNC gear set of a higher grade steel in 2008 and then everything went silent. When I blew my gears this spring I PM'd him asking about availability of a set of his improved XR gears and no response. MrGadgets was aware of his work per his posts on Articfriends thread on this subject. Does anyone know why this all went silent? Did Merc buy out his work to maintain the status quo?

Never happen. Ever. But hilarious none the less!!!

As most find, it takes a huge stack of money to build a gear. Lots have looked into it, but few have proceeded past the check..
I am doing the same cryo, polish treatment that Smitty uses. It seems senseless to do the upper gears as fast as they fail. But we have seen some improvements in the lower gears. The lower pinion gear is much softer than the driven gear. Seeing a failure at 7hrs use, the pinion gear was pitted and the driven gear looked like new (like they should).

I was not thinking that anyone could afford to develope a new drive gear especially for such a relatively small market. I was interested in the cryo treated gears.

I know from Smitty's thread that he was having accelerated lower Bravo drive gear wearout issues and not accelerated upper gear wear out issues.

I am not clear what you are saying. Are you saying that the upper XR gears wear out faster than the lower drive gears or the lower drive gears wear out faster than the upper XR drive gears?

Are you saying that Smitty and/or you tried the cryo/polish treatment on the upper XR gears and it provided no improvement in gear life?

No.. his upper gears are older than 5yrs, so are mine. We both froze and polished the uppers and it seemed to help, right up till the teeth start to break off a the root. Since then it seems pointless to band aid a bad gear. It takes a lot of work to get the bearings out and get them treated, just to have the gear fail and then some one says, well did the cryo hurt it?
So I have shyed away from doing the upper gears, actually I have been encouraging people to go with the SCX and not worry about the XR upper gears. Or go with the X gears and friends have had good luck with that.
I still thing the cryo is agood thing, just need a good gear to start with..

Dick

Thanks Dick. I want to make sure that I understand what you are saying.

So you and Smitty tried the cyro and polish on the upper XR gears that were a vintage older than 5 years and it seemed to improve the gear life but instead of their normal wearing out they started to crack at the tooth root and had to be replaced for that reason. Is that correct?

Then you and / or Smitty also tried the cyro and polish on the upper XR gears of current vintage and there was no improvement in gear life versus upper XR gears of current vintage. Is that corrrect?

Or did you and / or Smitty not try the cyro and polish on the upper XR gears of current vintage because they are so bad to start with? Is that correct?

Mr Gadjets, the reason for all my questions about the cryo is to be fully informed and ready with the proper decision the next time my gears go south. My Bravo X1 is a 2004. It's history is as follows: 90hr @425hp, 26p B1 stock, and OEM lube, 80hrs@490hp, 40hr@ 540hp, 162hrs@625, for a 382hr lifetime total. Other than the first 90 hours all the rest was with a labbed B28 and Redline Shock Proof Heavy Gear Lube. Hull is 3700# and drive shower is from Nordic and is marginal (re upper drive oil temps reach 270F+ and still climbing during extended WOT runs). I have always been carefull to use only 50% throttle on plane out with the X1 gears. Most hours are cruising at 2500 rpm or wake boarding at the same with lots of starts and stops. Hard running is usually only for AFR testing one cylinder at a time when I change something. I knocked off two upper gear teeth this spring(lousy timing) while WOT testing a 26P5X and was not being quite as dilligent about the 50% throttle max on plane out. I had just changed the lube. The lower gears were found to be pitted as well. I have always found fine iron dust on the drive magnets at end of season lube change but nothing larger. Drive was rebuilt with XR gears so now I am in the same boat as you guys. I thought I was putting a better gear in for my power. After XR gear breakin done to the letter I checked the upper magnet and zero iron dust found but the lube seemed darker than normal especially for such low hours. Maybe from the lubes used in rebuild assembly.

I had 2 new XR upper gearsets cryo treated
about 3 years ago. ( and yes, getting the bearings out
of them is real fun)

One set started chunking out in less than a year,
the other set is still ok ( knock on wood)

What was your experience with non cryo'd XR gears?

Pitting, cracking, breaking teeth off...broken cases.
....all the normal stuff