As stated, what is the safe maximum running rpm’s on a 225 Sho? Is 6200 to high or right at the top end?
As stated, what is the safe maximum running rpm’s on a 225 Sho? Is 6200 to high or right at the top end?
Full throttle rpm range stops at 6000 so I'd try and bring it down alittle
Red line RPM is 6000.
It is always possible for the red line RPM to be exceeded. It is the operators job to not let that happen.
A properly propped Yam is one that will let the motor turn at or near red line RPM when the boat is loaded, in summer time conditions (hot and humid) with the motor trimmed up to the point of maximum efficiency. And no further. If boating in cold and dry weather, or with less than a full load. take care not to let the motor over speed. Or install a different propeller.
Flashed mine to 7k but 6200 hardest I’ve run it. That dog will eat when get RPM up
Thanks for the information. I was under the impression that 6200 was the red line for the engine. Reason I ask is I’m trying to seat the rings. The 25 T2 will not get the rpm’s up high enough. 5500 max, that’s with a hydraulic plate. It’s almost like exhaust back pressure is robing the engine. So I have gotten a 23 razor 4 blade to get closer to the upper end of the rpm range. With a full load, I should be able to maintain at or near 6000 rpm’s. I’m also under the impression that a flashed motor will allow rpm’s to climb near 7000. So if 7000 is max or near max rpm range, how will 6200 harm the engine? I understand it will flag in the ECU, but will it really harm the engine, just curious.Originally Posted by yam911
I have a F150, and I was bouncing off the rev limiter at 6300 rpms. Backed down one pitch and I'm perfect @ 6000 rpms. Would the reflash remove the rev limiter from the ECU?
Depends, if you want the limiter removed, the flash can do that, but if you don't it won't. It's all what you tell the guy that does the flash. RPMs make horsepower. From what I have read, flashing, and keeping the RPM limiter, doesn't accomplish a lot for the expense and possible warranty exposure.
If your hitting 6200 in winter I say you are fine. In summer it will be 6000
T2 suck. Big mistake by Yamaha
Which T2's? What is the mistake.
They are stiffer and don't exhaust like the T1 look inside to see the difference
They are also not accurate from the factory. Apparently in a hurry to get them out the door and quality control not so good. If you have one get it checked I bet it is out of tune (different pitches each ear etc.)
Having just dissecting my blown up 250 SHO, I would definitely not turn it over the recommended redline of 6000 RPM, idle for at least 10 mins. before leaving dock,once rings have seated and no longer "making oil" switch to the best quality synthetic you are comfortable affording and change at the recommended interval. Just going to say "Crank Oiling" is the weak link in this engine design. "Just my 2 cents" building 8000 RPM engines for 40 years.
12 lbs 9 oz caught on 4/28/1975 Lake Eufaula
Is that just during break in or period?
Frank
Stock 2012 SHO 225 with 255 hours
2000 ZX 202-C hull
I would say 8,500 rpm before stuff starts to break. Could be more like 14k rpm. Stock limiter is around 6,200
No, not breakin only, for the life of that engine . I can't get pics to post here but a single thrust washer (about 1 square inch total area)supports the weight of the crankshaft and flywheel. Mine was cooked and grooved the crank,the lower with no load on it looked like it came of the assy. line Crank and rod bearings have no locating tabs to prevent them spinning in the bores should a speck of carbon or metal come through the crank oil hole and grab the bearing causing it to spin, cutting off oil supply to the bearing and causing a chain reaction.
What year was that SHO?
David Patten
Automotive and marine technician.
2012 259 HRS
The reason why I started this thread is because I can only turn my 25 T-2 at 5500 rpm, that’s with a hydraulic jackplate. I recently got a 23 pitch Razor 4. I was concerned that by dropping 2 pitches with an overall smaller blade diameter, I could possibly be above 6000 rpm. Well that wasn’t the case. I got to run it on Lake Toho this past week, low 80 degree air temps and water temps in the mid 60’s. I really had to run it pretty high on the jackplate. 8 on the Atlas, trimmed really high, I was able to get her up to 70 @ 5800 rpm’s. I have a BassCat Caracal, and the Cats generally don’t like much trim at all. But to get the bow up and rpm’s up, I had to run everything really high. Also, the hole shot was really poor, had to set the jackplate at 12 just to get a decent hole shot. It was much slower than the 25 T-2. Do y’all think I have an engine issue? Or is it just a weak engine?
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