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Compression Range


oldgrumps
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15 Beta evo 2T overheated and blew coolant out overflow. When refilling system noticed white foam. Flushed system and ran bike around the block. There was still foam. No white smoke out of exhaust but it does seem easier to kick start. Betausa thinks blown head gasket. Did a compression test and got 127 at a 1000ft altitude. Does anyone have normal compression values? Any suggestions on possible cause damage?

 

Thanks

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I will not go into the reasons here but a simple compression check on a 2T trials is pretty pointless. Take the head off and inspect.

 

You can get a chemical reaction kit to test the coolant for combustion by products, but from you symptoms probably no point.

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ok pulled the head and found the white foam goey stuff on the inside of the head cover. No obvious leaks or breaks on the gasket. The Cylinder looks good. Unfortunately I discovered a pin hole on the exterior of the cylinder. I stuck a pick inside and measured the depth of around 2.3mm. This is appears to be some kind of casting defect. The hole does not go all the way through, but wondering how close to a intake port or water jacket it is. My bike is not even 6 months old yet. Emailed Beta.

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Edited by oldgrumps
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Bit more than a pin hole. I don't see anything that would indicate water or fuel/air mixture in or out of the hole. I suppose the real question is why did it overheat in the first place? If that hole went through to the water jacket the system would depressurize and over heat but it would also spew coolant. If the hole went into the transfer port you'd see spooge on the side of the cylinder and the bike would run lean causing it to overheat. I would hope that's a casting defect Beta will replace but it it isn't leaking and they don't replace the cylinder that hole should be filled with JB Weld or something similar just to make sure it doesn't start a crack or punch through to the transfer port.

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I wonder if Beta got a bit over extended. With GasGas going under Beta could sell everything they could produce perhaps even a few bikes that shouldn't get out the door? It's not an uncommon scenario when a manufacturer falls into a windfall of demand.

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For a 6 month old bike what is going on around the base of the cylinder?

Have you spoken to your dealer or let him have a look at the bike?

Where are you located, If in the UK John Lampkin will sort it out he is very fair!

Sorry just noticed your in the USA.

Edited by jfc
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  Sorry that is dirt where the cable shroud runs at the base of the cylinder. So I put a new head gasket cylinder in and ran the bike for 15 minutes around the block. Got it hot enough so the fan was running. Let it cool down and checked the coolant. Guess what? It still had foam sludge! So it appears the head gasket was not to blame. So thinking it might be the water pump seal I drained the oil and let it sit overnight to look for water. I don't see any water but the oil looks cloudy. Remember the oil only has 15 minutes run time on it. My friend said he thinks thats normal that the oil will not be golden brown clear after running it.

  The good news is that Tim Philg from betausa said they will take care of the hole in the cylinder. So I'm sure they will have to figure out whats causing the foam problem. I will post pictures of the bike and oil. Its early here in hawaii.

 

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Old

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Ok here is the pictures. The plastic container was hard to shoot because of the thick plastic. I hope my dealer tiki cycles and betausa can get this sorted out. These make awesome trail and trials vehicles. For those of you wondering what riding in hawaii is like just checkout youtube under Sunday Rides. There is other videos of trail riding in hawaii also.

 

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Edited by oldgrumps
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OK follow up. Took the bike down to my dealer and he discussed it with Betausa. They feel there is no danger of it cracking further and there is sufficient wall thickness left. He said to just drill it and then fill it with epoxy. If the cylinder should ever crack in future they will still warranty it.

 

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Edited by oldgrumps
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