canyon 306 top speed

[mb1]

i have 2011 canyon 306 with twin 350 Yamaha's my top speed with painted bottom is 46 mile but the Grady white in there performance web sight saying its 59 mile
may be the bottom paint is a factor, but it should not be that much.. the difference is almost 13 mile :hmm .. is there owners with same problems, and i would like to know there top speed.

*** my top speed with trimming the engines and same factory blades

Thanks

 

[ElyseM]

something sounds off. the performance numbers published by gw and yamaha are pretty close to achievable in real world; in my experience.

my 330 will turn 45 mph with 4 blade props, and it's a lot heavier than you.

you do need to measure in calm seas; no significant current, wind or chop. good luck, ron

 

[magicalbill]

Is there a chance your speedo on the Yams might be plugged up, giving you a slower reading? Mine gets a piece of seaweed or whatever in it often.

If your using your GPS on your chartplotter, then your back to square-1.

What are your rev's at top speed?

 

[stevblutu15]

Something simple... Are you comparing knots to mph? 46kts is roughly 59mph

 

[mb1]

my RPM is 5700 and the GPS is in mile not knots and the sea was perfect

 

[ElyseM]

rpm not too bad, i find it hard to hit exactly what they turn in testing. but the speed is pretty far off. are you sure the bottom is clean?

just thought of something; you are running 89 octane?

 

[mb1]

actually i am running in 98 octane

 

[ElyseM]

actually i am running in 98 octane

are you running avgas?

best we would get is about 93 octane with e10.

i'm no tech, but could the high octane be causing the engines to reduce performance? they clearly state that you will not get the same performance if you use less than 89 octane; maybe the 98 octane is having an impact on the top end. what does your tech tell you about the difference in perf #'s?

also, assume the props are fine with no damage.

 

[NOTHING ELSE MATTERS]

I think your GPS is set wrong. I had a 306 with 250's and i was getting more speed than you. Your RPMs are also OK. Check your GPS again, statue mph is knots.

 

[mb1]

actually i am running in 98 octane

are you running avgas?

best we would get is about 93 octane with e10.

i'm no tech, but could the high octane be causing the engines to reduce performance? they clearly state that you will not get the same performance if you use less than 89 octane; maybe the 98 octane is having an impact on the top end. what does your tech tell you about the difference in perf #'s?

also, assume the props are fine with no damage.

I am using the Grady in Kuwait we have here a 98 octain

 

[wrxhoon]

Guys,

You will find in USA octane rating differs from the rest of the world, 98 octane in Kuwait is the same as 93 in USA.
In USA you use AKI rating
RON Octane Rating x 0.95 = AKI Octane Rating )
98 RON Octane x 0.95 = 93.1 AKI Octane (US measure)
100 RON Octane x 0.95 = 95 AKI Octane (US measure)


mb1,
One mile = 0.868976 nautical mile so 46 knts is about 53 mph.

 

[family affair]

Im not running a boat like yours, but this could be related. My top end numbers are good, but compared to the factory test my midrange numbers were poor vs rpm. I had my factory prop cupped and picked-up 5 MPH at 3800 rpm. It also appears my engine is mounted 1 hole too low.

 

[mb1]

Im not running a boat like yours, but this could be related. My top end numbers are good, but compared to the factory test my midrange numbers were poor vs rpm. I had my factory prop cupped and picked-up 5 MPH at 3800 rpm. It also appears my engine is mounted 1 hole too low.

I tried deferent props, but the only thing i did not try bringing the motor one hole up..but does it help?

 

[ElyseM]

Im not running a boat like yours, but this could be related. My top end numbers are good, but compared to the factory test my midrange numbers were poor vs rpm. I had my factory prop cupped and picked-up 5 MPH at 3800 rpm. It also appears my engine is mounted 1 hole too low.

I tried deferent props, but the only thing i did not try bringing the motor one hole up..but does it help?

the mounting position per yamaha was hole #2.
http://www.yamahaoutboards.com/sites/de ... 350txr.pdf

if the motor is lower there will be more drag.

considering your location, what is the gps accuracy? i'm pretty sure waas is not global and i would have to guess that civilian accuracy in the me would be degraded currently (if selectively possible). can you hook up a temporary xducer with a speedo wheel to check it out?

 

[family affair]

Moving the engine one hole won't give 13 MPH, but if the height is wrong the change will help. If the engine is mounted correctly, don't make a change for the sake of changing. I have another thread on this site regarding engine height and prop cupping. That thread should help you determine if your engine height is wrong.

 

[Tuna Man]

I own a 2006 Marlin (also 30 feet long) with F250 engines turning four blade props. I can acheive 46mph on a regular basis with a light load and my bottom is painted. I would assume that with a total of 200 extra horsepower and a lighter boat, you should be able to run at least ten miles per hour faster than me.

 

[rus dunbar]

I have twin 350"s on my 30 ft freedom. Try triming all the way up so your rpm comes up to 6,000. No tabs. I get 57 mph. When my rpm are under 6,000 speed falls off.