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Total loss of compression, or Spark


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6 hours ago, gaortiz said:

 


BetaUSA needs to find out what's going on with this...many model years are doing this...even the 2018s....

 

I think it’s prudent not to jump conclusions until it’s known exactly what the issue is. I would like to know exactly what each issue has been for other Beta you have referred to also.

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2 minutes ago, Wild Alaskan said:

ok four stroke cycle:

1. piston moves down with intake valve open bringing mixture in to combustion chamber

2. piston moves back up compressing mixture (very little typically get by the piston during this stroke)

3. piston moves back down normally with compustion pressure above it

4. piston mover up with exhaust valves open completing the cycle

 

Now lets say we have a lot of blow by happeneing

1. is realively unchaged other than a little crankcase air can get above the piston

2. is where some pressure can be built as the air additional air that came through the intake valves can get squeezed in to the crankcase

3. if there is still enough compression for combustion of some sore tho occour this stroke can also result in more air and exhaust gases getting in to the crank case

4. is fairly irrelevant as the exhaust valve are open.

 

here is a demonstration of this concept, note the trouble he goes through with oil spraying out of the engine as the blow by increases

 

Ok but we still don’t know what krans issue is exactly. The bike isnt apart.  This might be great if what has gone wrong isn’t easily determined when taking the bike apart. The bike just died. It’s not sounding like catastrophic failure for now.. 

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5 minutes ago, hawaiidirtrider said:

Ok but we still don’t know what krans issue is exactly. The bike isnt apart.  This might be great if what has gone wrong isn’t easily determined when taking the bike apart. The bike just died. It’s not sounding like catastrophic failure for now.. 

you are exactly right about no one actually knowing what happened, but he posted a list of symptoms on an online forum and he is going to get theories based on those symptoms. I just finished a KTM with those exact symptoms. Unless the bike had been sitting on it side for some reason or the oil was way overfilled the oil in the airbox is a major red flag.

here is a ktm that "suddenly got water in the gas or something" according to the customer.

gshdUntitled.jpg

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No compression should be an enormous clue ....

Oil dripping out the air filter box is the next massive clue....

If you don't understand the workings of a 4 stroke engine, you could just take some wild guesses... Or you could just make sh!t up....

Pressure that gets by the piston and rings is what would pressurize the crankcase... The area where the cam is located is connected to the crankcase via the timing chain cavity...

Low compression and blowing blue smoke is one thing (oil would blow out airbox here too) .... Sudden loss of compression and oil coming out airbox when none has previously is another thing altogether... Catastrophic engine failure...

 

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1 minute ago, gaortiz said:

This is not the same thing at all and it’s good to note but there are a bunch of variables. It could be just that the oil was overfilled for example or if he dropped the bike and oil went in the airbox. Or if he had a small crash or other things. 

Lots of times a very common mod is to take out the crankcase vent hose away from connecting to the airbox. On my 525 RS Beta I took out my crankcase hose from being connecting to the airbox. Oil would go in the intake in a fall. It’s an old time mod. Look it up and lots of bikes have done this mod. 

Krans issue isn’t what you linked. I bet that’s a brand new Beta and someone overfilled the oil but idk.. should watch more to see what that Beta rider eventually found out at the end. 

 

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3 minutes ago, mixxer said:

No compression should be an enormous clue ....

Oil dripping out the air filter box is the next massive clue....

If you don't understand the workings of a 4 stroke engine, you could just take some wild guesses... Or you could just make sh!t up....

Pressure that gets by the piston and rings is what would pressurize the crankcase... The area where the cam is located is connected to the crankcase via the timing chain cavity...

Low compression and blowing blue smoke is one thing (oil would blow out airbox here too) .... Sudden loss of compression and oil coming out airbox when none has previously is another thing altogether... Catastrophic engine failure...

 

Right now there are symptoms and it may or may not be catastrophic. Hope not but maybe.. It’s guessing until the bike comes apart right now.  So your bet is a blown bike.. ok

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This is not the same thing at all and it’s good to note but there are a bunch of variables. It could be just that the oil was overfilled for example or if he dropped the bike and oil went in the airbox. Or if he had a small crash or other things. 
Lots of times a very common mod is to take out the crankcase vent hose away from connecting to the airbox. On my 525 RS Beta I took out my crankcase hose from being connecting to the airbox. Oil would go in the intake in a fall. It’s an old time mod. Look it up and lots of bikes have done this mod. 
Krans issue isn’t what you linked. I bet that’s a brand new Beta and someone overfilled the oil but idk.. should watch more to see what that Beta rider eventually found out at the end. 
 

Dude you didn't read any of the comments on the post....he did NOT overfill the oil in that post. Read all the updates. [emoji26]
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I'm not guessing anything.....

I just came in to help you guys out....

I'm not sure if this is indicative of Beta riders in general... But there is a stark lack of understanding of engines in general here.... Shocking actually.... I have been a rider and race engine builder for over 40 years... And I don't think I have ever seen a group with this complete of a  lack of understanding....

If the symptoms have been described correctly... There was a catastrophic engine failure...

 

 

Edited by mixxer
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48 minutes ago, THE KRAN said:

Oh, yeah, this should be good...

Piston failure causing oil out the vent tube, and nothing else, is not really possible....because the RING seal and vent tube are what hold the pressure in balance.

A worn out or stuck RING would cause a severe imbalance in crankcase pressure do to blow-by, forcing pressure up into the valve train, and oil out the vent tube.

A failed piston would cause catistrophic failure, which would of course have oil blowby as ONE of the issues.....hardly the 'tell tale sign'.... as the motor would lock up.....

Now to be fair, I suppose a 'failed piston' could only fail at a ring groove.....and not dismantle itself.....but I have never heard or seen such a thing.

 

 

good edit, If you are really lucky it could be a little piston scuff that stuck the ring that would cause your symptoms. Serious piston seizures/failures in no way guarantee a locked engine as a hopelessly screwed piston can still end up scraping through a lot of extra revolutions as it slows down the engines mass, rear wheels mass and the bike  as well if the clutch is out. As far as your last comment, see the piston in my last post. Ring gap wasn't large enough for whatever abuse the bike was going through and it blew through the top of the piston cracking all or the other rings in the process and sending piston pieces everywhere. bike wasn't seized and would actually almost start occasionally, it had 35 psi compression even in that state.

I really hope for the sake of your wallet that your air filter was just over oiled and leaking and the ignition just came unplugged and this is all speculation over something silly.

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14 minutes ago, gaortiz said:


Dude you didn't read any of the comments on the post....he did NOT overfill the oil in that post. Read all the updates. emoji26.png

I read all the comments . It’s not unlike comments Ive read for my rfs ktm motored 09 Beta in the past. Have you looked up anything on Beta crankcase hose mod or ktm crankcase mod ? Or any motorcycle crakcase mod where the crankcase hose has gone to the airbox?? Go read some. I did the mod on my 525 RS Beta rfs motored bike. Hey it’s good to check especially with a brand new bike but my guess it’s still not a big issue and for sure it’s not the same as Krans issue but idk . We will see. 

Seriosly look it up. There’s even a kit for ktm and other bikes at Blais racing

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37 minutes ago, mixxer said:

I'm not guessing anything.....

I just came in to help you guys out....

I'm not sure if this is indicative of Beta riders in general... But there is a stark lack of understanding of engines in general here.... Shocking actually.... I have been a rider and race engine builder for over 40 years... And I don't think I have ever seen a group with this complete of a  lack of understanding....

If the symptoms have been described correctly... There was a catastrophic engine failure...

 

 

I see your on the CRF230 thread a lot. What's your experience with the Beta FI motor? 

 

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1 hour ago, THE KRAN said:

I did a search and came up with (5) posts about oil out the breather tube.....and no follow ups, and no conclusions.

 

 

Man, this sucks KRAN! 

Please keep us updated on what is actually going on. The Monday morning quarterbacking is unreal! 

Please remind me year and model? 

When you were riding up the hill was there any indication before the problem? 

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I understand.  
I think we should wait to see what KRAN shares before we jump to conclusions.

Once again...just referencing something that I saw that seemed slightly similar. Just trying to help the guy out. I feel bad for the guy, especially since he's a fellow Beta owner and SoCal guy!
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Just now, gaortiz said:


Once again...just referencing something that I saw that seemed slightly similar. Just trying to help the guy out. I feel bad for the guy, especially since he's a fellow Beta owner and SoCal guy!

Me too, and appreciate the sentiment. Hopefully KRAN understands were sympathetic towards his terrible situation! 

just lots of guys jumping in with "expertise" doesn't help one bit. 

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