Max RPM

[steph]

I have a 1984 60hp Johnson (model#J60TLCRE) on a 1984 14.5' Peterborough open bow. I bought a Tinytach to see my RPMs. On WOT my RPM is 6250 (which seems high to me I think) and 27MPH which I though would have went faster. Are the RPMs to high?

 

[iwombat]

Re: Max RPM

If you want more top speed, you're certainly in the range where you could consider going up a pitch or two.

 

[steph]

Re: Max RPM

By incresing the pitch want it be to hard on the engine? What is a good WOT RPM?

 

[iwombat]

Re: Max RPM

Not sure of the specs on your particular engine. I'm sure someone else will chime in here. But, I think 6k is at the top of the recommended range. 5800 would probably suit you pretty well, especially if more speed is what you want. You'll sacrifice hole-shot, but I'm guessing with 62k WOT you got plenty of hole shot to give up.

 

[rickdb1boat]

Re: Max RPM

5000-6000 is the recommended operating range at WOT. I would, as suggested, shoot for 5800-5900 RPMs. Going up 2" in pitch would put you close. You may see a gain in top speed..

 

[F_R]

Re: Max RPM

Agreed, 27mph out of 60 hp on a 14' boat, something is wrong. Put some prop on that thing.

 

[steph]

Re: Max RPM

Thanks again guys, I'll go shopping for a new prop and keep you informed. Is the TinyTach a reliable and accurate tach?