Z Flats Flyer hits the water!

A place to celebrate your first launch with video and/or photos

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hoodman
Posts: 2912
Joined: Thu Nov 10, 2011 8:48 am
Location: Lafayette, IN

Re: Z Flats Flyer hits the water!

Post by hoodman »

That hull shape should be capable of just about any reasonable speed. When you switched props, did your WOT rpm increase or just dropped top speed?
Matt

Building a Geronimo......!
viewtopic.php?f=2&t=25139

Alexile
Posts: 15
Joined: Sun Nov 17, 2019 4:15 pm

Re: Z Flats Flyer hits the water!

Post by Alexile »

After I changed the prop my WOT RPM went from 4000 to 5000. My top speed went down just a little. I'm still a bit suspicious that I'm not actually getting full throttle. There is a part called an "accelerator pump" that has an arm that attaches to carburator 4 which is like the master carb that the other three are set to. I am suspicious of this arm as it slightly restricts the butterfly valves in the carbs from opening absolutely completely. But also, other than manually pushing on them there seems to be no way the butterfly valves can be in a completely horizontal position, although I will say it very close, and with my limited experience I'm not sure of the differrence it can make.

Alexile
Posts: 15
Joined: Sun Nov 17, 2019 4:15 pm

Re: Z Flats Flyer hits the water!

Post by Alexile »

I made three adjustments: I re-cleaned and re-synced the carbs, left the gas cap a little loose, and re-routed the fuel line just after it enters the motor (it was taking a very sharp turn there and now it's not)
The results were phenomenal. I'm pretty sure the bend in the fuel line was the culprit of not reaching full rpm's at WOT.
I was getting 31 mph at 6000 rpm and could have gone a little more but didn't want to push it.
Because I have more headroom I think I will change back to the 16 prop (its a 13 now). That should get my WOT at full throttle around 6000 and give a few more MPH.
It seems like the bow is slightly tilting down when I'm on plane. Is this normal for the Flats Flyer? While on plane I tried adjusting the tilt and it didn't seem to make a difference. Just wondering what others are experiencing with this hull.
Thanks again!

hoodman
Posts: 2912
Joined: Thu Nov 10, 2011 8:48 am
Location: Lafayette, IN

Re: Z Flats Flyer hits the water!

Post by hoodman »

Sounds like your on the right track. Something was obviously not right. Once you get up on the planing surface there's not much you can really do to change the running attitude other than moving weight around.
Matt

Building a Geronimo......!
viewtopic.php?f=2&t=25139

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