sharkcus
Breakin' the atmosphere.
- Location
- Strongsville, OH
I picked up a cheap SN with a bad 650 and put in a (literally, new) 701 with a new RIVA head. I did not swap electronics (yet) so I am stuck with the 650's rev limiter. Single carb. No exhaust leaks. Starts up fine, every time, without primer.
I took it to the lake yesterday. The water temp was probably 40. It starts up but seems to "chug" a lot at lower rpm. At first, it almost sounded like it was running on 1cyl, but I tested and it's definitely running on both. (Dies with 1 plug not connected). So I took it out and something didn't feel right. I have owned a (stock) 650 SN for a few years, so I know what to expect, but it actually felt like less power than a stock 650. And it also seems to hit the rev limiter earlier than my 650. Or maybe it just felt like it. On my 650, I don't remember actually hearing ignition studdering when it hit the limiter (expect when I have it out of the water on a wave). On this one, when I gun it, it gets up but then studders, almost "buzzes" if that makes sense.
Engine felt cool, not overheating although I did disconnect the temp sensor because there isn't a spot for it on the new head. I didn't do anything special to the sensor, just coiled it up and ziptied it. Installed a pisser and clear lines, everything is getting water.
I've never been on a 701 before, and maybe I was expecting too much, but it didn't have that low end "punch out of the water" feel to it. Even my 650 had a little "punch". Yes it would get up on a plane, but it felt slightly than my 650. I'm using the same pump (literally) that I had on my 650, so thats not it.
Also, my plugs were black. One one side of the PTO plug's ceramic had a lighter spot. Wasn't white but definitely not as dark as the MAG cyl. Almost like it wasn't firing as much. (yet, at idle, when i disconnect the plug, it stalls). I'll attach pictures when I get home. It's hard to describe how the ski was running. It got me up, but seemed to "studder" kind of how an engine feels like when missing a plug. Very bumpy.
Thoughts? Disconnected temp connection causing issues? Too rich? Would 650 electronics (rev limiter) make a 701 run WORSE than a 650? Other ideas? If I discovered it was really only running on 1 cyl, it wouldn't suprise me because thats the kind of lack of power it feels like.
I will also do a compression test tonight and post results. As I'm writing this, I'm starting to wonder if it is compression on the PTO cyl. That would allow it to continue to run, but maybe not that great. and misfire under load?
I took it to the lake yesterday. The water temp was probably 40. It starts up but seems to "chug" a lot at lower rpm. At first, it almost sounded like it was running on 1cyl, but I tested and it's definitely running on both. (Dies with 1 plug not connected). So I took it out and something didn't feel right. I have owned a (stock) 650 SN for a few years, so I know what to expect, but it actually felt like less power than a stock 650. And it also seems to hit the rev limiter earlier than my 650. Or maybe it just felt like it. On my 650, I don't remember actually hearing ignition studdering when it hit the limiter (expect when I have it out of the water on a wave). On this one, when I gun it, it gets up but then studders, almost "buzzes" if that makes sense.
Engine felt cool, not overheating although I did disconnect the temp sensor because there isn't a spot for it on the new head. I didn't do anything special to the sensor, just coiled it up and ziptied it. Installed a pisser and clear lines, everything is getting water.
I've never been on a 701 before, and maybe I was expecting too much, but it didn't have that low end "punch out of the water" feel to it. Even my 650 had a little "punch". Yes it would get up on a plane, but it felt slightly than my 650. I'm using the same pump (literally) that I had on my 650, so thats not it.
Also, my plugs were black. One one side of the PTO plug's ceramic had a lighter spot. Wasn't white but definitely not as dark as the MAG cyl. Almost like it wasn't firing as much. (yet, at idle, when i disconnect the plug, it stalls). I'll attach pictures when I get home. It's hard to describe how the ski was running. It got me up, but seemed to "studder" kind of how an engine feels like when missing a plug. Very bumpy.
Thoughts? Disconnected temp connection causing issues? Too rich? Would 650 electronics (rev limiter) make a 701 run WORSE than a 650? Other ideas? If I discovered it was really only running on 1 cyl, it wouldn't suprise me because thats the kind of lack of power it feels like.
I will also do a compression test tonight and post results. As I'm writing this, I'm starting to wonder if it is compression on the PTO cyl. That would allow it to continue to run, but maybe not that great. and misfire under load?
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