RPM Range

[Nosnibor]

Hey y'all. I've been pretty successful this season so far learning how to boat and what not. This past weekend once I got un-docked and just coasting in forward with no throttle I noticed that RPM's jump back and forth (not anything new). Something like 2000, 1800, 2100, 1900, 2000....just all around those ranges.

First is that normal like a car? and if not where should I start?

 

[JrSenior]

My 2005 Sportster with the 155 hp 4-stroke has a bit of a stutter at under 3000 rpm (basically any speed under planing speed). Had several mechanics opinion and it might be a lean condition due to the ethanol in the gas. So I run ethanol-free premium; yes it is hard to find. This partially resolved the problem. The fix may or may not be to have the ECM reprogrammed by a BRP dealer. At running speed mine is happy and so am I.

 

[Nosnibor]

My 2005 Sportster with the 155 hp 4-stroke has a bit of a stutter at under 3000 rpm (basically any speed under planing speed). Had several mechanics opinion and it might be a lean condition due to the ethanol in the gas. So I run ethanol-free premium; yes it is hard to find. This partially resolved the problem. The fix may or may not be to have the ECM reprogrammed by a BRP dealer. At running speed mine is happy and so am I.

Yeah when I am running it seems like it stays within 20+/- rpm

 

[rcguy]

My Seadoo in low speed moves around 1850 to 1950 rpm back and forth and I use ethanol free gasoline. I guess it's normal for these engines. When I hit planning speed 5200/5500 rpm depending on conditions the rpm don't fluctuate much at all.

 

[Nosnibor]

My Seadoo in low speed moves around 1850 to 1950 rpm back and forth and I use ethanol free gasoline. I guess it's normal for these engines. When I hit planning speed 5200/5500 rpm depending on conditions the rpm don't fluctuate much at all.

Thanks, I feel like what I am seeing is normal then. I think it's always been like that since I had it but now that I am not freaking out so much about trailering and docking I'm starting to notice other things.