Can it get any worse???

[standupwannabe]

:disappointed:I have just spent the last 48 hours crying in my beer. I was at the lake enjoying the end of summer on my RN SJ (701) when all of a sudden, Kaboom!
The bottem end let go and my crank came through the case below the rear cylinder (exhaust side). Today I pulled the motor out and found that the damage extends to my cylinder (scored wall and broken skirt on rear jug) and my dome is toast. Basically I have an expensive anchor. I'm going to post on "WTB" for a complete motor, but my question is; if I didn't suck in water, what would cause such a catastrophic failure? (I run 94 octane gas and the best synthetic pre-mix money can buy). I did a compression check a few months ago and was at 185 on both jugs. I don't race and would consider my self a non-aggressive rider (seldom if ever hit full throttle). Is this situation common, or was it just a case of bad luck???:dunno:

 

[McDog]

I feel your pain, dude.

 

[tor*p*do]

185 is borderline with pump gas
should mix 50:50 with race gas.
may have got a bad batch . . . . . .

 

[LBE]

(seldom if ever hit full throttle)

There is your problem. :laughing:

But seriously tho, sorry to hear that. Did you check the reeds? Most bottom ends don't blow unless they are being reved or raced. Just my experience. But mabey something fell in the cases? Reed screws? some type of bolt??
At least it is at the end of summer.

 

[XFT LOU]

Thats awful, maybe rod bearings.

 

[standupwannabe]

It looks as if the reeds are "carbon tech" and have not suffered damage. There is however needle bearings scattered throughout the case. Perhaps I should post a pic on the "carnage" forum (not for the faint of heart).

 

[hermanns]

At least it didn't sink too, that would have been worse, well unless you have really good insurance

 

[Jetaddict]

Was there just recently with my 1200 Blaster, bro. I feel your pain. The thing is, there rarely is any advance notice, and sometimes it just isn't due to anything you did "wrong". When it's time, it's time. My B1 was running incredible, and all of a sudden...BAM...I wasn't even going all out on it when it went. Sucks.

 

[Ottis]

definatly rod bearings, probably had water in them at one time, the bearings begin to skid insted of rolling and it oblongs the rod, causing it to hit the case, I've seen alot of triples do it not so many twins, sucks bro!!

 

[standupwannabe]

I was checking out Riva's website and they sell "PMC" replacement motors. Has anyone heard anything (good or bad) about these units? Like I said on my WTB forum, I do not have anyone close by me that can assemble an engine for me, so this may be an option for a complete motor. Thanks in advance for all the feedback.

 

[WaveDemon]

185 is borderline with pump gas
should mix 50:50 with race gas.
may have got a bad batch . . . . . .

low octain won't make a crank come apart. it'll melt pistons though.

 

[WFO Speedracer]

I was checking out Riva's website and they sell "PMC" replacement motors. Has anyone heard anything (good or bad) about these units? Like I said on my WTB forum, I do not have anyone close by me that can assemble an engine for me, so this may be an option for a complete motor. Thanks in advance for all the feedback.

Don't even waste your time with those guys.I put two of their NEW 720 replacement engines in Seadoos,neither one made it out of warranty.On one the center crank seals went bad,which means complete rebuild.On the other one the front crank seal went bad and took out the front crank bearings.On both of these engines they used non-stainless bolts throughout.I also put in a PMC rebuild which I throughly pressure tested and inspected.I could not get it to run properly and installed larger pilot jet to get it to run right. The reman engine lasted less than an hour before it locked up,it never made it past half throttle,I was running double oil and the cooling system was workin flawlessly.

 

[SUPERTUNE]

Just rebuild it yourself, get a hot hod new crank, get cylinders bored or nows the time for a 85mm big bore resleeve kit, find a used set of cases, use oem crank seals and put it together using help here and a service manual. Sorry to here the bad luck, but this is a 2 stroke and they require rebuilt and or new cranks pretty often as a regular maintenance.

 

[WFO Speedracer]

You are in Macon Ga. there are plenty of people around that area that would probably be happy to help you rebuild your engine besides Lehr performance is not that far from you.Supertune is dead on ,I am sure someone here would be glad to help you out as well,I would but I am near Montg Al. Which is quite a drive,if you want to make the trip however I will fix you right up.Be sure to bring a twelve pack of Corona extra.:Banane35:

 

[standupwannabe]

Wedoseadoo; I'm actually in Vancouver Canada. There is my problem Yamaha Canada has not imported Superjets into the country since the late 90's (due to low volume of sales). Therefore, any Superjets that made there way into the country were imported as used/previously owned units from the US (I could not buy a new superjet from a Canadian dealer if I wanted to!). For this reason, none of the dealers/shops want to touch the standups because they have no one that has any experience working on them. (SXR 800s however, are available to purchase new at Kawasaki dealerships, and as a result, most standup riders own these where I live). Thanks for the advice on "Lehr performance". I'll look into what they can provide.

 

[WFO Speedracer]

Supertune that posted earlier can fix you up as well.Sorry I was looking at mcdog's location instead of yours.My bad.

 

[Lakeman]

Just rebuild it yourself, get a hot hod new crank, get cylinders bored or nows the time for a 85mm big bore resleeve kit, find a used set of cases, use oem crank seals and put it together using help here and a service manual. QUOTE]

This is some good advise above. I was in the same boat as you were a couple of years ago. It is not hard to rebuild these motors. I rebuilt my motor and it ran the next year. That gave me some confidence to do more. But if not, I am sure there are people closer to you than you think that can lend a hand and help you put it together once you get your new parts.

 

[MADMAT]

I sooooooooooooooo feel for ya too man.

I'm a computer geek and I found rebuilding 2 smokes to be pretty dang easy as long as you have all good new parts and a machinist that knows how to bore and hone.

Good luck and take advantage of these guys willing to help! Especially for beer!