Yamaha Superjet questions

[BartW]

First apologies for the posh-ness of this post,
But swmbo convinced me to buy a Yamaha 701 standup jetski, for extra fun on Blue Angel ;-)
We found a very good condition used example locally in Belgium, and that will soon be shipped to the boat in Italy.
As we know absolutely nothing about Jetski’s let alone a standup model, here some questions:

2stroke Fuel:
What would be the best 2 stroke oil-fuel ratio, for this Yamaha.
Didn’t read the manual yet, but usually folks on here know better ;-)

Maintenance:
Apart from flushing the jet, what kind of regular / yearly maintenance is recommended ?
former owner only used in fresh water, never flushed and lost the adapter.
Where can I get that hose adapter for flushing ? ok I'll try the local jetski dealer

Cover:
Long ago there was a post on here that mentioned a Australian co, that makes covers for Yamaha ob’s,
they probably also make covers for jetski’s ?

Lifting straps,
any idea / example for a "non" exposed strap attachments ?

Oh yes and last but not least:
any recommendations for driving it ?
I remember there is a experienced but retired jetski driver and regular poster on here ;-)

 

[Portofino]

How good are you at balancing ?
Ski ?
Snow board ?
Paddle board ?
Skate board ?

If none of the above get some knee pads and elbow pads --- save a trip to A+ E and consider a cycle helmet .
The water is soft ,but the jet ski isn,t it's harder than your kneecaps ,head and elbows .

Faster you can go the more stable it is --- waves permitting ! -it's counter initiative

Yup do fresh water flush every time there's an awfull lot of aluminium alloys .
A lot of beach use will knacker -blunt the impellers and fuel for two stroke 40 to 50 -1

Annual -bats go @€50 a pop so no biggie and the o rings on the tank and breathers .

Have fun :encouragement:

 

[MapisM]

First apologies for the posh-ness of this post

LMAO, you must be joking, B.
You should know by now that the subheading of "Motor Boat Forum" is "He who dies with the most toys wins"...

Can't remember if I ever mentioned it to you, but below you can see the stern of my old tub when I bought her (she also had a small rib, hanging from the davits).
The white thing is a Yam 650 Waverunner, the predecessor of the 700 that you are now considering, and I'm afraid I must tell you that I sold her PDQ.
Ok, the decision was also partly due to our wish to get rid of the davits, install an hydraulic passerelle with a larger swim platform and a larger rib.
But as a matter of fact, it also didn't deliver anywhere near the fun I expected.
I mean, potentially it can (I guess), but the learning curve for exploiting its acrobatic possibilities is so steep that my commitment was lost well before getting there...

And for having a ride around a calm bay while the mother ship is anchored, sit-down PWCs are much better than stand-ups in just about every respect: with a stand-up you can neither carry a passenger nor pull a doughnut, for instance - not to mention that you can't even stop quietly and have a look around...!
Besides, if it's sheer speed you are after, forget going as fast as you could go with a sit-down machine.
I suppose you are referring to Hurricane in your last line, and I'm sure he will tell you that his large and comfortable 200+ hp Seadoo was scary, when pushed hard (guess how I know...! ).
But trust me, a stand-up, even if not as fast, can give a whole new meaning to the world SCARY.
The one in the pic below was "only" a 650, possibly also a bit tired (the son of the previous owners used her for proper racing).
But I was never able to push her as fast as it could go - even in dead calm waters. It was THAT unstable.
And while the 701 is bound to be even faster, I am skeptic that they improved its seakeeping/stability, which is inherently poor in any stand-up PWC.

Sorry for being even more scaremongering than Portofino - btw, I disagree with him that the faster, the more stable:
yes, the thing has ZERO stability when going slow, but it's at high speed that it really becomes a handful to drive.

Bottom line: take care...!!!

PS: sorry also for not being helpful ref. your questions, but I didn't keep the thing long enough to deal also with maintenance etc.
Ref. lifting, I can only confirm you that mine had nowhere to attach cables, so the previous owner arranged the lifting straps that you can see in the pic.
Essentially, they formed a sort of cone at the bow, and a larger cradle at the stern.
These two sides were also connected underneath, to hold together, and were lifted with the two davits.

 

[BartW]

LMAO, you must be joking, B.
You should know by now that the subheading of "Motor Boat Forum" is "He who dies with the most toys wins"...

Can't remember if I ever mentioned it to you, but below you can see the stern of my old tub when I bought her (she also had a small rib, hanging from the davits).
The white thing is a Yam 650 Waverunner, the predecessor of the 700 that you are now considering, and I'm afraid I must tell you that I sold her PDQ.
Ok, the decision was also partly due to our wish to get rid of the davits, install an hydraulic passerelle with a larger swim platform and a larger rib.
But as a matter of fact, it also didn't deliver anywhere near the fun I expected.
I mean, potentially it can (I guess), but the learning curve for exploiting its acrobatic possibilities is so steep that my commitment was lost well before getting there...

And for having a ride around a calm bay while the mother ship is anchored, sit-down PWCs are much better than stand-ups in just about every respect: with a stand-up you can neither carry a passenger nor pull a doughnut, for instance - not to mention that you can't even stop quietly and have a look around...!
Besides, if it's sheer speed you are after, forget going as fast as you could go with a sit-down machine.
I suppose you are referring to Hurricane in your last line, and I'm sure he will tell you that his large and comfortable 200+ hp Seadoo was scary, when pushed hard (guess how I know...! ).
But trust me, a stand-up, even if not as fast, can give a whole new meaning to the world SCARY.
The one in the pic below was "only" a 650, possibly also a bit tired (the son of the previous owners used her for proper racing).
But I was never able to push her as fast as it could go - even in dead calm waters. It was THAT unstable.
And while the 701 is bound to be even faster, I am skeptic that they improved its seakeeping/stability, which is inherently poor in any stand-up PWC.

Sorry for being even more scaremongering than Portofino - btw, I disagree with him that the faster, the more stable:
yes, the thing has ZERO stability when going slow, but it's at high speed that it really becomes a handful to drive.

Bottom line: take care...!!!

PS: sorry also for not being helpful ref. your questions, but I didn't keep the thing long enough to deal also with maintenance etc.
Ref. lifting, I can only confirm you that mine had nowhere to attach cables, so the previous owner arranged the lifting straps that you can see in the pic.
Essentially, they formed a sort of cone at the bow, and a larger cradle at the stern.
These two sides were also connected underneath, to hold together, and were lifted with the two davits.

Well actually I was referring to YOU in my last line, but I remember also that you were not very enthousiastic about it . We have little to NO interest in a siton jetski, on the few occasions I sat on one, I found it immediately boaring...
This idea came from buying a seabob for the kids, but after a brief discussion, we thought that a standup jetski is more fun, so its mainly for the kids they are very good skiers, wakeboarders and monoskiers , and grandma also wants to give it a try ��

 

[MapisM]

its mainly for the kids they are very good skiers, wakeboarders and monoskiers , and grandma also wants to give it a try ?

Ok, that makes sense then. Just tell them all to take care...
And also what PF said about wearing some protections is worth considering! :encouragement:

 

[Pinnacle]

and grandma also wants to give it a try ��


We will need to see that pic, B!

 

[MrB]

Also be prepared not being able to walk for days after, it's a killer on the legs. :encouragement:

 

[Seekingsun]

Haven't logged on for a while but after seeing this thought I'd add my tupence worth- ive owned lots of superjets over the years from basic 701 jets up to 1100cc custom jets and hulls.

Engines are pretty bomb proof in stock form and given its age Im
Assuming its relitively new? the only thing you should check is the compression, should be 150psi per cylinder and if it's slightly lower is fine as long as it's within 5% of each.

They remain largely unchanged since 1996 (pre 96 was the square nose 650
As seen in the pic above) until 2007 when the chimes were changed underneath to make them better racing skis. From
2007 onwards the only thing that changed was the colour and the stickers.

All run twin 38mm twin carbs and a 144 pump.

I have always run mine on Mobil 2t racing oil on a mix of 40:1. If in a warmer climate.

As for flushing there's plenty of flush kits on eBay for £15 to £20. You can get a reverse flush kit but I've never been keen.

As for riding I would recommend (if it doesn't come with it already) having some decent matts fitted to it. You will begin on your knees and it takes its toll the first few times. You will spend a lot of time swimming after it so make sure you take plenty of breaks or it will just get boring fast.

If you need a diagram of where to fit the new flush kit or check the current one just ask and I can pm you one. Takes all of 10 mins to fit a replacement.

There's no major annual maintenance except fogging the engine if it's not going to be used for some time and left on the back of the boat. Just google fogging spray, again quite cheap and all you have to do is spray it into the carb intake when the engine is on idle. I use seadoo oil for the engine and bay after each ride and flush with salt use, sounds like a lot but in reality is 5 mins. If your going to use it in the sea I would recomend fitting a bilge pump, these also help when washing the engine bay down after use. The standard bildge is a syphonic type which only works when the ski is under way (suction from the low pressure side of the pump).

They are light enough for two people to lift I would suggest a tow strap for the front, these go through the stock bow eye are again cheap and found on eBay, These make it easier to pull up.

As for covers there are plenty of us stockists for covers and the stock Yamaha cover is over £200 new

A quick eBay search turned this one up https://www.ebay.co.uk/itm/112440323865

Jumping ahead ..If your enjoying it and want to do a bit more than race around, if you want to do some jumping in the waves then get some foot holds fitted, these are cut into the tray and alow you to stand with your feet side by side which I find more stable in the sea when there's any kind of chop. The basic ones don't strap your feet just allow them to be wider and side by side.

They are great fun and a great way to keep fit too

Cheers

A

 

[MapisM]

They remain largely unchanged since 1996 (pre 96 was the square nose 650
As seen in the pic above) until 2007 when the chimes were changed underneath to make them better racing skis. From 2007 onwards the only thing that changed was the colour and the stickers.

Since as I understand you have experience on the whole range, I'd be curious to hear about the differences between pre 96 and the following models.
As I said previously, at high speed the 650 I used to have is the most unstable and dangerous thing afloat I've ever tried - and just to put this in perspective, I tried several fast boats, including a Mercury Racing 2.5 EFI powered 20' catamaran capable of 3 digits speed, if you see what I mean... :nonchalance:

 

[Hurricane]

Besides, if it's sheer speed you are after, forget going as fast as you could go with a sit-down machine.
I suppose you are referring to Hurricane in your last line, and I'm sure he will tell you that his large and comfortable 200+ hp Seadoo was scary, when pushed hard (guess how I know...! ).

Tee Hee

A few years ago, I had a go on a standup jetski.
It took a couple of hours to master it but I was a lot slimmer and fitter then!!

Our Sit Down Seadoo Jetski was one of the fastest things that I've driven - SWMBO managed to get 70 MPH out of it.
I suspect that a stand up would do nothing like that - even if you wanted to.

Anyway, back to the point.
Go for it - ours was great fun for a couple of seasons - then it got in the way.
I suspect that something like a Yamaha Superjet will not take up as much space and could be a longer term "fun machine".

During the two years of ownership, I made a short video - this reminds us just how much fun we had with it.



Full screen link
https://www.youtube.com/tv#/watch?v=baxSZH9cIaQ

So,, as I say - go for it and enjoy.
Just take the usual safety precautions and you won't regret it.

 

[Seekingsun]

Since as I understand you have experience on the whole range, I'd be curious to hear about the differences between pre 96 and the following models.
As I said previously, at high speed the 650 I used to have is the most unstable and dangerous thing afloat I've ever tried - and just to put this in perspective, I tried several fast boats, including a Mercury Racing 2.5 EFI powered 20' catamaran capable of 3 digits speed, if you see what I mean... :nonchalance:

Hi MapisM

As you say they are unstable which is what gives them their manoeuvrability and also what makes them a lot of fun to ride and more of a challenge than the big modern sit down skis.

To answer your question the earlier 650 jet as pictured above shared the same deck underneath as the superjet right up to 2007

as i understand it evolved like this..

- 90 to 93 was the gen 1 650cc (its know as the square nose superjet as you can see from your picture) this was a single carb 61x engine putting out 50hp

- 93 to 96 was the gen two square nose with an uprated engine output to around 63hp still using the same 61x cases a lot of jet ribs used this engine

- 96 to 2007 gen 3 superjet had a new 62t engine putting out 73hp with a round nose (known as the round nose 701) this has the same bottom deck as the gen 1 and gen 2 with the same handling characteristics.

- 2007 on wards the bottom deck was changed to allow the ski to carve better and to keep up with the kawasakis in racing, believe it or not this actually ruined the appeal of the ski for many as the way the earlier skis handled was part of the fun, being able to spin the ski out to a tail stand etc is what its about, they are all equally unstable. You will see that the earlier skis 1996 to 2007 are pretty much the same price used as they price is reflective of the conduction of the hull / engine not the age. Its actually quite rare to find a bone stock jet as they have massive following still, bit like finding an unmolested ford escort xr3 from the 90s.

i have several skis from over the years and also have a 2015 seadoo gtx 215. While the seadoo is great for the kids due to its stability i constancy get the superjet out for the shear fun factor.

The 650 square nose was the precursor or all the modern day stand up skis and racers and a bit of legend, current aftermarket hulls and custom skis can cost up to 35k with all the latest bits attached and although modified still use the bottom cases from the old Yamaha 62t engine, they definitely got something right!

hurricane mentions the outright speed, a stock jet would be lucky to achieve 40mph on glass flat sea but this feels like 100mp when your standing up.

Falling off at that speed can hurt and often winds people, they are a lot more fun at lower speeds popping little jumps you will soon learn when you can and cant give it WOT.

Don't forget your lanyard at all times and suitable impact vest. Some riders use downhill bike riding helmets made by 661 etc these have a tendency to water log and the peaks can cause neck issues if you hit the water at high speed. The best helmets IMO are gecho helmets, I wouldn't say there are a must to be honest as learning you wont being going fast enough to warrant one but that decision is yours.