Major update and a bit of sad/ lucky news.
I haven't posted in a while since it's summer where I live which only lasts until mid sep before it starts to cool off again.
That said i'm waiting for parts again so I have a bit of time to post.
The good news:
This thing is so much fun! Oh man!
The machine shop I brought my pistons to (which specializes in snowmobiles) ordered 83mm pistons for my 61x...Then bored it to that size without calling me. They easily could have only gone up one step (stock bore was within acceptable limits but mild scoring). So they accidentally bumped me up to 735cc. I was stoked but a little freaked out that if something happened I was in for new sleeves...
Followed Ericsons machine & performance break in guide on youtube. Worked out great for me. Also tuned it his way with great success. Low speed on trailer out of water, high speed on trailer in water. Couple tries and I had my chocolate colored spark plugs. On the water it jumps out of the hole and pulls hard all the way to the moon.
735cc, Wiseco pistons 83mm, Yamanube porting templates and H.S.I. high comp head gasket. Single 44 carb with 95g spring, 120L 150H jets. I'll report back on how many turns out I was on the screws. Honestly cant remember at this moment.
Other stuff:
- Kemimoto finger throttle off amazon is pretty great for the price. Has a pretty good hook on it for your finger to rest in and looks really good.
- Anodized aluminum (amazon) fat bar adapters bolted up to the stock steering to accommodate my:
- TAG mini mx bars that I purchased a decade ago for my honda 50, 750mm width.
- Cheepo lock-on grips.
Static trim:
My 2010 superjet had static trim and I loved it. I'm a light rider so I always had it maxed out to help keep the nose up.
- Went to home depot plumbing section, grabbed a 3" rubber coupler (comes with gear clamp) and attached it to the nozzle. You'll have to squirt some silicone spray to get it on since they have the same ID, and you need to get it over the nozzle but totally possible. Once you muscle it on just tip in up slightly. WOW huge difference. I had to dial it back down a touch. Tipped up just a few degrees is perfect. Tips the nozzle up when you nail the gas before a wave but still rides nice and stable at speed.
The bad:
Went for a solo ride in the river last Sunday. Was running like a dream, got cocky and ended up about 10km from the launch before it suddenly got loud. First thought was "poop poop poop" followed by "the riva pipe prob just blew a gasket so I'll just idle to the nearest ramp and uber to my truck. A few seconds after that though I noticed no water but exhaust blowing through my pisser. Against logic and instinct I decided to try and limp it to shore instead of killing like I new I should have.
A few seconds later (still at idle) I noticed the idle was dropping and it quit. At this moment I thought I just locked up my 1.6h motor. I was still in the middle of the river and noticed I was sitting low in the water. "no prob I'll flip on my bilge" Nothing. My cheap ass amazon bilge switch quit on me. I have versiplugs but they are only good when you're moving. And from my experience they weep a bit of water when you're just sitting.
I pop the hood to see if there is anything obvious. The only thing that was obvious was the steam coming off my motor and the 4" of water sloshing around in my hull with a brand new bilge pump just sitting there staring back at me.
Waved down the first boat that sailed by. They were kind enough to tow me about 6km to their home marina. Still about 4km from my vehicle. Not willing to beach it on rocks I tied it tight to the dock. No phone, no wallet I decided to jog 4km in my wetsuit back to my car.
Returning to the marina with my vehicle there was about 10" of water in the hull, sitting real low but still afloat.
First thing after pulling it out of the water was reach up through the grate and try to turn the motor. Success! Felt good but I still didn't know what happened. Got home and realized I overlooked something major/ minor. When I put the ski back together I used stainless gear clamps on all the waterlines. All except the one at the pump inside the hull. I missed this one and that's the one that failed. Which would also explain why I was taking on water. I basically had a 3/8" hole in the back of the hull.
Further investigation:
Even thought the motor was free didn't mean I was in the clear. I just built this thing and want it to be reliable. Pulled the head and to my surprise the cylinders were in good shape. A little sticky which my best guess is the 2T oil burning up got gummy and slowed the motor to stall out saving my ass. There are lines in the cyl's but I'm not sure I want to even call it scoring. I even had my wife run her tiny fingernails over them and she couldn't feel anything. Cleaned and oiled the hell out of them. With the pistons at tdc I'm able to move the pistons around laterally just slightly which in my mind proves no stuck rings.
Now that my mind is at peace the motor is ready to be yanked out so I can put the riva pipe back on. Which was still on as secure as it was day one even with the overheating fiasco which was a nice surprise. You read forums on those pipes and you would think they'd be washing up on show with how often people say they fall off.
New head gasket in the mail and a new (proper) bilge switch in the mail with it.
Photo dump: Pics are in order of the story with the sadness towards the bottom.
