29Fever575sci

Any update on the gears? I found some good material to make them out of.

pqjack

if the ols xr gears were better,one could sort of copy them?...just curious...

Uncle Dave

Then you are unique.

Several guys have done back to back testing and all have lost speed- some a lot, others a little.

The guys running 100+ seem to lose a bunch, the guys under a little

Curious how the XR replacement gear experiment is going.


UD

ROTAX454

Smitty, Paradox in post 4 has a point. I will add: What about the upper case floor? And yes, I would be interested in an approvement over the now stock Merc upper gear set.

articfriends

iTrader: (1)

Strongest thing I have ever found for a upper (not talking about gears but everything else) is to have Max Machine worx put there full length tower in it, billet clutch shaft, thick billet cap w/7/16 studs, chrome moly spanner nut . If all this is done to a upper and you could get gears to live I think it would last along time. My drive I have on my boat is using the original upper case that came on it new in 2000, I had Max Machine worx do all their upgrades to it then assembled it with early xr gears, I had a soft pinion gear start to scallop way back in 2002 or so then broke the floor out of a xr gear that was modified for a bigger bearing. Since then I have logged 300 plus hours, closer to 350-370 on the same upper gears and case. This was behind 700hp then 750hp, then 950 hp, then 1050-1100 hp and when I had them out recently they still looked almost like new. Once a full length tower is installed you don't have to worry much about breaking the floor near the tower since the new tower is postively located in the upper from top to bottom and the tower has a nice flange that spreads the load around. A little tower insert or the xr factory tower are a bandaid compared to what Max worx does. I do take my upper apart every 20-40 hours and inspect it. I am also still using my original cone clutch that came new in my drive in 2000, I thibk the total hours on that are almost 500. it shows some slight wear but yet even with 1000+ ft lbs of tq I have never had a problem with it, Smitty

Tom A.

After running my SCX uppers for a whole season now, I couldn't be happier! I can't tell if I lost any top end speed because I changed the prop slightly for better mid range. The best the boat ever saw was 119 on a fluke 55 degree day in Florida with less than a 1/4 tank. The boat was good for 112-115 normally. I saw 109 this summer and I'll bet with the other props she would have hit 112-115.
The best part is they didn't give me a bit of trouble, and the boat accelerates like a demon from 50-100 and that is where most "weekend races" in v bottoms are won.