Speed loss with B-Max drives
11-16-2004, 08:08 PM
#11
Platinum Member
Platinum Member
Re: Speed loss with B-Max drives
All I know is that everybody's experience says that 1.5's are faster than 1.3's
I picked up a mile an hour going from 1.5's (25 pitch) to 1.36's (23 pitch) myself. So my personal experience on my personal boat runs contrary to popular results.
I won't argue the hp difference to spin a Bmax, but all I know is that the gears and bearings in the uppers are MUCH LARGER. With gear oil and a 500hp torque load, physics tells me that there is more friction loss with larger gears and bearings. How much? No idea. But more.
And friend went from 1.36 XR's to 1.32 BMaxes and lost a touch. But not alot.
You don't buy BMaxes for extra speed. You buy them so you can KEEP going fast instead of getting the tow rope out.
I picked up a mile an hour going from 1.5's (25 pitch) to 1.36's (23 pitch) myself. So my personal experience on my personal boat runs contrary to popular results.
I won't argue the hp difference to spin a Bmax, but all I know is that the gears and bearings in the uppers are MUCH LARGER. With gear oil and a 500hp torque load, physics tells me that there is more friction loss with larger gears and bearings. How much? No idea. But more.
And friend went from 1.36 XR's to 1.32 BMaxes and lost a touch. But not alot.
You don't buy BMaxes for extra speed. You buy them so you can KEEP going fast instead of getting the tow rope out.
11-16-2004, 08:11 PM
#12
Re: Speed loss with B-Max drives
Originally Posted by mcollinstn
Some lose up to 2 mph.
If you are pushing hp's in the range to where an XR gearset is already smearing the gear faces under load, then the BravoXR is actually sucking more hp thru localized friction than the Bmax will. In that case there will be no speed loss with the Bmax.
I have a friend who is involved in a three boat trade-thru. The potential owner of his current boat is planning to do a power swap on it. This will leave a pair of 575SCi's and Bmax drives needing a home. Probably can be bought very reasonably. If you have interest in the motors or drives, PM. The complete construction of the deal is not complete, and buyers for those components can help to make it all work. Motors and drives are still in boat and running so you can see what you're getting.
If you are pushing hp's in the range to where an XR gearset is already smearing the gear faces under load, then the BravoXR is actually sucking more hp thru localized friction than the Bmax will. In that case there will be no speed loss with the Bmax.
I have a friend who is involved in a three boat trade-thru. The potential owner of his current boat is planning to do a power swap on it. This will leave a pair of 575SCi's and Bmax drives needing a home. Probably can be bought very reasonably. If you have interest in the motors or drives, PM. The complete construction of the deal is not complete, and buyers for those components can help to make it all work. Motors and drives are still in boat and running so you can see what you're getting.
