sand the bottom, sharpen the fins, adjust the hardware (fin angle, trim tabs, strut), move the cg around, sharpen and balance the stock prop. He could squeeze 6mph out of it easily, and now he's in the 40s.

Thanks. I'll tell him.

Sand the bottom??? I don't get it???

its called "trueing" the hull. Take a 3m sponge sanding block and sand the bottom of the hull near the rear. Usually the last 5" of the hull, which is in contact with the water the most. The idea is to remove the shiny clearcoat, but not to sand through to the bare fiberglass, which releases the surface tension and takes any imperfections (like a slightly raised edge at the transom) out of the hull that cause drag.

If you have the Revolt 30, they tell you about it in the manual. Always sand forward and backward, never side to side.

I wouldn't call scuffing the clear coat the same thing as trueing the hull... to me, trueing the hull is when you sand out any hooks/humps to make the bottom 100% flat.

You don't even need to remove the clearcoat, just scuff it so it isn't polished and shiny anymore.

+1 wp.
Trueing (blueprinting) the hull is a whole different thing from just scuffing the bottom to help aireate it.

I just purchased one of these and the first time I used it I lost speed after approx. 10 seconds of run time. I removed the prop shaft and reinstalled it to allow more room as it looked like it was binding. After a 5 second run the prop was binding again. It went from an approx. 6 mm gap to being tight during this 5 second run. Any thoughts on how to rectify this??

Thanks in advance

Originally Posted by Ritter1

I just purchased one of these and the first time I used it I lost speed after approx. 10 seconds of run time. I removed the prop shaft and reinstalled it to allow more room as it looked like it was binding. After a 5 second run the prop was binding again. It went from an approx. 6 mm gap to being tight during this 5 second run. Any thoughts on how to rectify this??

Thanks in advance

Buy a new flex shaft and collet from Offshore Electrics.

Did you grease the flex shaft before running? Grimracer speed grease is a must have for the stock flex shaft or any flex shaft for that matter.

Yep. Gotta grease the shaft before the 1st run and adjust the gap between the drivedog and strut bushing. You may have trashed the flexshaft during your 1st run. Have you inspected it yet?

I greased the flex shaft with a synthetic marine grease that I purchased from Advance Auto and set the gap at approx. 4 mm before the first run. The Grimmracer grease was out of stock when I ordered the boat. Did my choice of grease cause my problem?

I will buy a flex shaft and collet from Offshore Electrics to improve my boat.

What do I look for to know if the flex shaft is damaged? It looks ok to me.

Thanks for your quick responses.

No, the marine grease should work fine. If your flex shaft is broken, it will have snapped coils that are visible. Dont go buying a new one just yet. Just start eliminating things: can you spin the shaft in the stuffing tube? Pull the strut bushing and inspect it. Make sure the colet holding the shaft at the motor is very tight, and the set screw on the drivedog isnt loose, causing it to slide back into the bushing.

This thread needs some "visual aid" on a graphic empty page. Here's a video with a Revolt 30 (red & white) running in a P mono heat I shot a couple fo weeks ago.
Watch close around the 1:15 mark.

07 22 12 Heat 4 (2 min 11 sec)

LOL. the first boat took to the offshore bouy and everyone followed!

Your revolt is pretty loose, but it looked to be competitive speed wise with the rest of the field.

sometning amiss in this thread. First , when you set spacing at 6 mm which is 1/4" at strut and it absorbs the whole 6mm. This says your drive line is out of wack or else your using a small drive line is a small diameter wnd winds up inside strut. Replace entire drive line inside as parts BLEW-UP. Set dog-drive spacing at 3 /32" or 1/8". You'll understand once you delve into it. Your lucky you don't have our drought, no water.

Lets hear what you find out so all will know if it occurrs to them ok.