Triumph 150CC with Yamaha 70TLR

[jack7265]

I bought my 2005 Triumph 150CC new, and it came with a Yamaha F50TLR. It's the perfect engine if you only go fishing by yourself. It's very fuel efficient (Approx. 7.5 MPG) and was fast enough for me (Approx. 32 - 33 MPH WOT by myself). The only problem is that when I had someone sitting in the helm seat along side of me, it wouldn't get you on plane. I would have to send that person toward the front of the boat until I got on plane, then they could come back and sit on the helm seat. This was not only embarrasing, but could be dangerous since I would lose plane at times when I had to slow down to make winding curves in the bayous.

I researched the different outboards offered by all the manufacturers, and determined that the Yamaha 70TLR (228 lbs.) was within the transom maximum weight of 250 pounds, and was, in fact, 9 pounds less than the Yamaha F50TLR. The 150CC is rated for a maximum 60 HP, so the 70TLR is 10 HP over the maximum Coast Guard HP rating of the 150CC. I did the math for determining the maximum HP allowed by the Coast Guard ((2 x W x L) - 90)) for a boat with a 20 inch transom and remote stearing, which gave me a maximum HP rating of 100 HP for a boat of that size. So, beings the state of Louisiana doesn't have a strict policy on enforcing the maximum HP for a boat, I decided that 10 HP over the maximum HP rating of 60 HP was within reason, and not pushing it to the limit. The maximum speed at WOT only increased by an average of 3 MPH, but now I can get on plane with a passenger sitting on the helm seat, although I may take a while with a larger passenger (230 pounds).

I don't know why Triumph rates the 150CC at a maximum 60 HP, which is 40% below the HP as determined by the Coast Guard formula, but can only imagine it may have something to do with the maxium weight of 250 pounds for the transom. In all cases that I found, except the Yamaha 70TLR, any motor that exceeds 60 HP, exceeds the maximum 250 pound rating of the transom.

I've been satisfied with the Triumph 150CC from the get go, and now with the addition of a new 2007 Yamaha 70TLR, I feel as though I've got the perfect match of boat and motor.

 

[Cape Codder]

Jack7265-i Also Have A 150cc With A 50 Hp Yamaha. In My Opinion A 70 Hp Engine On This Little Boat Is Way To Much Power And Weight. I Have My Passenger Either Sit Up Front Or Do What You Do And Have Him Move Forward Until On Plane. Im Not Embarassed Or Shy About Moving People Around On My Boat. Having The Coast Guard Circling My Sunken Boat With Passenger With Me, Now That Would Be Embarasing

 

[Jan from Humboldt]

Guys I have the 150 with a Yamaha 40 and it will run at 28-30 @ 5900 rpm (WOT) with me and fishing gear, there's also no problem getting up on a plane.
However I have added a Hydrofoil fin to the lower unit, I use the 300 series.

My prop size is 11 5/8 x 11 stock aluminum Yamaha prop and I get a bit over 8 mpg if I don't run it too hard.

http://www.basspro.com/webapp/wcs/s...01_1103_200002007_200000000_200002000_200-2-7

 

[jack7265]

Cape Codder, If you would have read what I had written a little more thoroughly, you wouldn't have made mention that the Yamaha 70TLR is too heavey, because I had stated that the Yamaha 70TLR (228 pounds) is 9 pounds lighter than the Yamaha F50TLR (237). Yes, you can move people forward to get on plane, then they can move back to the helm seat and your okay, but for instance just yesterday, I had to slow down while going up the Barataria Waterway, for a shrimpboat moving fast with a deep draft, and at the speed I had to slow down for the large wakes, I would have lost plane with the 50 HP, but was able to maintain plane with the 70 HP. If you lose plane, that could be dangerous with all the other boats that are running in the Barataria Waterway. Also, because of the gear ratio of the 70 HP (1:2.33) compared to the gear ratio of the 50 HP (1:1.85), I'm only running 3 mph faster (average 34.5 MPH) which is still within reason, but have the power to move my boat with a passenger, all the fishing gear, ice chest, etc. which puts my boat at a weight of near full rated capacity.

You are entitiled to your opinion, and I respect that, but in my opinion, I have put an engine on my boat that serves it well, and is just enough power. A bass boat with 200 HP to 250 HP, now maybe that's too much power.

Cape Codder, you have a nice boat and the 50 HP you have on it is still a nice setup, I should know. I'm sure you enjoy your boat as much as I enjoy mine, so in my opinion, you have the perfect boat for your needs.