Rev Range for 5.2KC with 60hp Yammie High Thrusts.

[Lovey80]

Hello all you 5.2KC owners! As you may know I bought Dean1's 5.2KC a little while back. At this point it is fair to say that I am more than impressed. It is still hard to fathom how they get such a nice soft ride, economy, deck space and stability out of a 5.2m boat. Sunday headed out from Mooloolaba at around 530am. Swell was still around 2m with a bit of chop around from the SE. Heading to my mark into the swell saw me sitting on around 21kts no problem. The wind swung to the SW and immediately the swell and chop dropped off for a magic day on the water.

Around 12 we picked up and headed home in near glassy conditions with a following sea. Thought it would be perfect to test out the WOT figures. I played with the trim constantly to fine-tune performance. The average WOT running speed was a little over 25knots and around 5400rpm increasing to 27kts and 5700rpm coming down the face of larger swells. 3 people on board, live tank full, a small amount of ice and fish. Near full tanks (say 200l).

I am a little concerned that I may not be achieving a high enough RPM for the given load and may be putting a little too much work on the engines which may limit engine life.

Would like to hear your thoughts. Love the boat and looks like it may stay in the shed for many years to come. These engines need to do me until someone makes a 4st as light as these in 90HP so want to look after it.

Cheers

Chris

[warrior]

mate your 60 shoulld rev out to at least 5900 ,mine was on a heavy 4.5 and did 53 k top speed fully loaded ,it took a while to set it up correctly they are bullet proof and rev well under there blowing point i was told by the yammy boys .thats why they are all on the pro boats.i lifted the motor to get the proper revs it was one hole too low and only revved at 5700 ,good luck cheers AL

[Dean1]

Hey Chris glad your happy with her shes one special bit of gear hey. It must have been your old man i told but the next thing i was about to do to the boat was get the props shaved down about a 1/2 inch.. Ian ( Finding Time) on here got it done and reckons it mades a difference giving better out of the hole performance and about 200 300 more revs which really helped through the whole rev range.

Gavin at Victory Parts does it i think he quoted me $120 a prop from memory.

Solas does it as well.

If you wants Gavs number give me a yell.

Cheers..

[Lovey80]

Thanks Deano I will certainly consider that. Looking for as many opinions as possible.