First ride and only got 500ft

[danpalooza]

I'm going to tear it apart when I get some free time, I'll post what I find. And seeing how available and inexpensive the engines are made me not freak out as much as I was.  :yow

[jjs1234]

I just bought a '92 K75 RT today and was so excited to take her out on her first little ride. I pulled out of my place, gaining speed with a smile on my face, when suddenly my elation was halted after I shifted into second gear. An alarming CLUNK sound, followed by the rear wheel locking up, sent me in a panic. I squeezed the clutch in to stop the skidding and to try preventing from highsiding. Luckily I wasn't going very fast. I coasted into a nearby parking lot confused and frustrated. I test rode the bike earlier that day and it shifted smooth 1-5, no problems at all. The guy I bought the bike from was a mechanic and apparently he maintained it regularly (I'm not putting it past me that he could be lying). Anyway, only getting 500ft from my house wasn't a good way to start the relationship with my bike. Although I'm thankful I wasn't on the freeway when it happened. I will be taking her apart soon and let you know what I find. But in the meantime, anyone have ideas on what could have caused the transmission to fail like that?


-Danner

Not that it will come to it, but in-case you have to take the trans apart- no fear! its quite easy to do.


Edit: saw the pictures. Thats a total downer. I would like to know what caused this? Broken timing chain? Interested to see what the engine looks like with the crank-case cover off.

Best of luck! :2thumbup:

[Laitch]

Not that it will come to it, but in-case you have to take the trans apart- no fear! its quite easy to do.

I took apart watches when I was a boy. I had a box full of parts. That was easy, too. I had to buy one with my allowance when I wanted one that worked.

[jjs1234]

Yes it's easy to take something apart and not be able to put it together again... I did this when I was very young too. Telephones, really old computers etc.

As far as the trans goes the most difficult part is only if  you forget where the shims go.

Sent from my HUAWEI MT7-L09 using Tapatalk

[The Mighty Gryphon]

Looks like I may have been right about the thrown rod.  Did you look to see if the oil pressure sender was didsconnected?   Have you contacted the seller yet to see if he will give some compensation?

With the price of used engines what they are,the good news is that you should be able to part out your old one for a good chunk of what the replacement will cost.  Or have a nice supply of spares for cheap.  Too bad this had to happen at the start of the riding season.

[danpalooza]

The oil pressure sensor was connected. But I took the crankshaft cover off today. Turns out the connecting rod snapped. Any ideas how this could have happened? it did some damage.

[jjs1234]

I forget but somebody on here had me check my rods if they were bent. Hydrolock?

Wiki:

Hydrolock (a shorthand notation for hydrostatic lock) is an abnormal condition of any device which is designed to compress a gas by mechanically restraining it; most commonly the reciprocating internal combustion engine, the case this article refers to unless otherwise noted. Hydrolock occurs when a volume of liquid greater than the volume of the cylinder at its minimum (end of the piston's stroke) enters the cylinder. Since liquids are nearly in-compressible the piston cannot complete its travel; either the engine must stop rotating or a mechanical failure must occur.

[danpalooza]

Looks like I may have been right about the thrown rod.  Did you look to see if the oil pressure sender was didsconnected?   Have you contacted the seller yet to see if he will give some compensation?

With the price of used engines what they are,the good news is that you should be able to part out your old one for a good chunk of what the replacement will cost.  Or have a nice supply of spares for cheap.  Too bad this had to happen at the start of the riding season.

Good call Gryph, you called it.

[danpalooza]

I forget but somebody on here had me check my rods if they were bent. Hydrolock?

Wiki:

Hydrolock (a shorthand notation for hydrostatic lock) is an abnormal condition of any device which is designed to compress a gas by mechanically restraining it; most commonly the reciprocating internal combustion engine, the case this article refers to unless otherwise noted. Hydrolock occurs when a volume of liquid greater than the volume of the cylinder at its minimum (end of the piston's stroke) enters the cylinder. Since liquids are nearly in-compressible the piston cannot complete its travel; either the engine must stop rotating or a mechanical failure must occur.

Not sure how water could get in the engine. I live in AZ, it hardly ever rains here.

[jjs1234]

Fuel... idk foreign material in the chamber

Sent from my HUAWEI MT7-L09 using Tapatalk

[The Dude]

Thanks for showing us the insides.
Is the big end seized?The rod is twisted and broke.

[richarddacat]

Bummer.

[Scott_]

It's also possible that there could be a broken valve at the head end that could have caused it.

Sent from my SCH-R970 using Tapatalk

[TrueAce]

Wow. That's discouraging. Where will you plan to go from here? Bummer,indeed........sorry for your trouble.

[danpalooza]

Dude, not sure what you mean by the big end. The crank doesn't move at all if that's what you mean.

Scott, I'm planning on doing a tear down to investigate further.

Ace, it was a day ruiner for sure. My plans from here is to source a new motor and make a project out it. I was thinking about turning her into a scrambler since I'll have her completely torn apart.

[The Dude]

Yeh,terminology is terminally misunderstood."Big end"is the larger con(necting) rod bearing and runs on the crank shaft.If it is seized up it may indicate that a lubrication failure caused the con rod to snap.
This is the most likely cause,imho.

[TrueAce]

There you,go, Danpalooza, sure it's a kick in the teeth, but after you coast for a bit, jump back on that mule and make it your bitch! :clap:

[danpalooza]

Dude, I'll take a look when I get the engine completely torn apart

Ace, no way I'm giving up yet!

This where I got this weekend. Hopefully next weekend I'll get the engine more torn down.

[TrueAce]

Oh, Man, I think I just figured out what caused your problem...................sibling rivalry with a certain shiny silver Honda.

[The Dude]

Dude, I'll take a look when I get the engine completely torn apart

Ace, no way I'm giving up yet!

This where I got this weekend. Hopefully next weekend I'll get the engine more torn down.

The motor is toast.Best concentrate on finding a next one and get back on that ride...the dead motor isn't worth mending,just curiosity as to why?I guess.
  You mentioned the crank shaft was seized.Can you rotate the bolted cap of the broken con rod on the crank?Take the cap off,even?Inspect what you reveal.
All the best.

[danpalooza]

Ace, I wasn't planning on mending it. I just wanted to see what caused the failure (as I'm sure you and other curious motobrickers do too on this thread).

 I'll try to rotate the rod on the crank to see if it can even turn.

[danpalooza]

Oh, Man, I think I just figured out what caused your problem...................sibling rivalry with a certain shiny silver Honda.

Ha! That's actually my dad's bike, he was helping me out with the tear down. That new goldwing is pretty sweet though.

[tsnap]

True ACE? " There you,go, Danpalooza, sure it's a kick in the teeth, but after you coast for a bit, jump back on that mule and make it your bitch! :clap:"

This is a donkey mecca

tom :hehehe

[TrueAce]

Well, I say "Donkey-Wonkey"..........my people's & me always been more partial to mules, sort of runs in the family, if ya know what ah mean....

[TX brick]

In the first picture that was posted I see mud on the cover and a distinct dirty line near the intake snorkel. I wonder if the bike was submerged and hydro locked?

That could have damaged the rod and it broke later.