XR drive uses 30 more HP?

[FASTERDAMITT]

Why are posts reading the XR drive uses 30 Hp more to operate than a Bravo1 or XZ. Is the lower unit larger in size? I have a XR upper abd a Bravo1 lower.

[Craig]

That seems like a lot of power loss compared to a standard Bravo. Anytime you have to turn more mass or a mass is harder to move by design, it'll take more power. That's why the B-Max will slow a boat down, but you gain the strength that the bigger gears provide. In F3, the boats that ran a No.6 would be slower then the same boat with a Bravo, but the 6 gave them the reliability the Bravos lacked in the rougher water when the boats were prone to flying.
Craig

[Havasu Hangin']

I heard the straight-cut gears cost 25HP...
http://www.planetsmilies.com/smilies/happy/happy25.gif

[Charley]

I wish I could have paid 25hp... my xr cost me like $6000

[Havasu Hangin']

Originally posted by Charley:
... my xr cost me like $6000
Is that with or without the evenly spaced zip-ties?
http://www.planetsmilies.com/smilies/happy/happy25.gif

[DMB]

I run the B-Max,it does run about 5 MPH slower and eats a little HP but the gears are significantly larger.So it is an acceptable loss for me,this unit has been very reliable so far.
Twice last year I went to the river,only to have my cockroach sit on the trailer the whole time due to the outdrive.
25-30 HP ? you won't even miss it,but you will still be enjoying the headspace that only a good day boating can bring.
Why would the straight cut gears take more HP to spin,are they larger?
Uneven zips included,evenly spaced extra. LMAO HH that was funny.

[Craig]

DMB, I think the gears are about the same physical size, but when you use an angled gear (wrong technical name I know, but it escapes me at this hour!!!helical??) such as the XZ you gain two things. 1, is it's an easier, smoother contact and 2, it's quieter. The down side is you lose an amount of material for the gear itself hence the reduced strength. If I recall the XR's might be forged differently as well.

[FastCats]

Hi Guys,
We buy a lot of both Xr and Xz drives and most come from Bob Teague. In his words the XZ is the fastest because of the bevel cut gear, The XR is slower because of the straight cut gear and the windage in the case from the straight cut gear. The XR is stronger, for sure. The BMAX is much stronger but much heavier as well. We use a XZ up to and including our 600hp engines and go to the XR for all others up 900, after that we go to the BMAX. Hope that this helps!
Scott

[hulshot]

so I shouldn't buy a Imco SC to handle 1000hp, but instead buy a heavier bulkier B-Max