Racers! Water Pump Modifications?

[motosix]

For those racers out there (seemingly few?) that have rebuilt the bottom end of your 675s, I am curious if anyone has stumbled across any ideas to help with the parasitic loss from the water pump shaft seal?

The oil pump polishes up nicely and is quite free in motion, but the water pump seems to bind quite a bit. Since it is an oil/water boundary it can't be opened up too much, but I was surprised to find how stiff it was.

Any clues? (besides simply slowing down the pump with the KIT oil pump gear and chain)

[antirich]

Wayne at PowerTripp can best answer that question. He's done quite a bit of work in that area.

[motosix]

Originally Posted by antirich

Wayne at PowerTripp can best answer that question. He's done quite a bit of work in that area.

Is that information he may freely share? Tuners often are tight lipped about their secrets (and, rightfully so).

[motosix]

Wayne is beyond helpful and extremely knowledgable on these 675s!

His email is wayne@power-tripp DOT com

Phone: 205.663.4304
Fax: 205.663.4149
103 8th Ave. NW
Alabaster, AL, USA
35007
www.power-tripp.com



(Thanks Wayne!)

[Dave73]

Any insight you'd like to share?

[motosix]

Not a whole lot a normal racer could do without making a mess of the pump assembly. "lots of hours" to replace the seal with something that spins more freely...

I have a damaged one that I will experiment with this next off season, but since the seal is a pressurized oil/water barrier (at different pressure levels too), it is a risky proposition.

Another big issue in there is the bad impeller design which is prone to cavitation, but I don't have much insight on how to go about solving that problem. Wayne would I bet.

[samwise_i]

Originally Posted by motosix

Another big issue in there is the bad impeller design which is prone to cavitation, but I don't have much insight on how to go about solving that problem. Wayne would I bet.

The newest pump has a different impeller design. The oil pump is also different.