BannedCR500Riders.com

Ok,

I was riding around the my house, lots of back roads and I was riding for about 35 minutes. I got on a paved section and went "all-out" for a 5th gear pinned run....It worked great for about 10 seconds then the motor locked up at about 70mph! By some stroke of common sense I pulled the clutch in and coasted to a stop. It was a wild ride for a few seconds!!!

This has happened to me before, about 4 years ago and the bike restarted just fine. Not this time. It seems to have no compression, heck you could kick it over by hand. It just wont fire...real weird.

It was about 30 degrees outside. Any ideas? Thanks!

Yea.... its broke.

Thanks! Thats what I thought...What "technically" happened?

It seized, broke a ring, broke a piston - any and or all of the listed items? Crack the POS open and see for yourself - four cylinder base bolts and you'll know after you get the other stuff out of the way.

Ok,
Has this happened to anyone here? I have used the search button, but all I find is a load of crap, with no real answers. Is this common?

97CR500R wrote:Ok,

I was riding around the my house, lots of back roads and I was riding for about 35 minutes. I got on a paved section and went "all-out" for a 5th gear pinned run....It worked great for about 10 seconds then the motor locked up at about 70mph! By some stroke of common sense I pulled the clutch in and coasted to a stop. It was a wild ride for a few seconds!!!

This has happened to me before, about 4 years ago and the bike restarted just fine. Not this time. It seems to have no compression, heck you could kick start it by hand.

It was about 30 degrees outside. Any ideas? Thanks!

HEY!!! Happy Birthday!!!

[quote=""SOLID Bro!!""]HEY!!! Happy Birthday!!! [/quote]

Best present I could have!

You running a Wiesco?

AlisoBob wrote:You running a Wiesco?

I can't remember, it was about 4 years ago when I had a shop do the top end. I would guess 60% yes...I already know they aren't the best.

97CR500R wrote:it was about 4 years ago when I had a shop do the top end.

You had it rebuilt 4 years ago, locked it up 4 years ago too, got it free and have been riding it fine until now... and it locked up again?

AlisoBob wrote:

97CR500R wrote:it was about 4 years ago when I had a shop do the top end.

You had it rebuilt 4 years ago, locked it up 4 years ago too, got it free and have been riding it fine until now... and it locked up again?

I am sorry Bob, I don't know the exact day, hour, minute & second of when it seized up on me. It was about 4 years ago. Then I had the top end done about a week later (still about 4 years ago...less a week or so). Now it has done it again. (about 4 years from when I had it rebuilt.)

she ate her pigs

see if theres still a part# ontop of the piston, post that # here and we'll start there. take a picture of the inside of the reed cage area before the jug comes off too k

So your saying it:

1. Locked up
2. Kicked it free and rode it
3. Then had it rebuild ( 4 years ago)
4. Rode it fine until now
5. Siezed, and lost all compression

Correct?

If you didnt change your "summer jetting", and rode it in 30 degree weather... it was prolly leaner than shit.

If your piston is a Wiesco, and it wasent drilled... it was prolly the classic Wiesco "ring smear on the exhaust bridge" failure.

Happens all the time, very weird it lasted 4 years though...

Yes, thats the correct series of events. Perhaps the bridge was not recessed like it should have been during rebuild?
I guess its time to "dig-in"

dad locked up a wiseco in the garage, was clearenced, relieved, drilled, blablabla and barely got the rads warm NEW. I have that piston in the box, he was so mad he ran to the dealer and threw an oem in it and rode the snot out of it same day. just had a nice idle, said give my a helmet and squeek it locked up

Roostius_Maximus wrote:dad locked up a wiseco in the garage, was clearenced, relieved, drilled, blablabla and barely got the rads warm NEW. I have that piston in the box, he was so mad he ran to the dealer and threw an oem in it and rode the snot out of it same day. just had a nice idle, said give my a helmet and squeek it locked up

So what do you recommend? Pro-X or Vertex or???

oem, then vertex, not prox

i have a prox n.i.b.

Floats a tad to low, bowl runs dry, it bogs and melts the exhaust side of the piston.

Been there done that

Roostius_Maximus wrote:dad locked up a wiseco in the garage, was clearenced, relieved, drilled, blablabla and barely got the rads warm NEW. I have that piston in the box, he was so mad he ran to the dealer and threw an oem in it and rode the snot out of it same day. just had a nice idle, said give my a helmet and squeek it locked up

same thing happened to me on a break-in after a complete top-bottom rebuild on a KTM 380.

warming it up in the driveway, a faulty wrist pin clip failed and Squeek. perfect half moon shape on the bore. replaced the clip and rode it anyway.

A little oil in the fuel works wonders...

Heres some "not-so-good" pics of the piston and jug.

The bottom of the piston looks ok:



The top is a different story. What piston rings? :





The jug has scoring also:

FZ1426 wrote:A little oil in the fuel works wonders...

Good point

It's easy to make a mistake on the mixing ratio, and from the looks of the pictures....quite likely in this case.

I do 32 to 1. That should be a good enough ratio right?

Ive seen all kinds of smeared exhaust photos, but I can see through all the way to scoring on the intake side.....

Intake side never is supposed to score like that.


Looks like no oil to me.

If the piston was too tight, It would not have waited 4 years to do this.