Crankshaft Failures
QUOTE
Originally posted by thomez
The reliability stuff is scaring me away from the machine I love. I'm afraid to ride it now - it's rediculous, I know.
Me after thinking of my Cannondale a month ago =
Me thinking about it now :confused: :cry:
For those interested in oil pressure, it is listed on the dyno sheets that are on Cannondaler. I always thought it was low...
:confused:
The reliability stuff is scaring me away from the machine I love. I'm afraid to ride it now - it's rediculous, I know.
Me after thinking of my Cannondale a month ago =
![biggrin.gif](http://www.cannondaleriders.com/forums/style_emoticons/<#EMO_DIR#>/biggrin.gif)
Me thinking about it now :confused: :cry:
For those interested in oil pressure, it is listed on the dyno sheets that are on Cannondaler. I always thought it was low...
:confused:
I hear you, loud and clear.
bphillman: Isn't that just something else to go wrong? I hope some good comes of this, and someone gets a concrete answer once and for all.
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Oil pressure not needed!
This is the kicker guys.We do not need oil pressure to any of our bearings!A car with inserts for bearings must have oilpressure to hold the insert and part apart.The only spot in our entire motor that is somewhat like this is the smallend rod bearing and wristpin.All twostroke motors also use ball or needle bearings in them yet not one of them has a oil pump the oil is just vaporized along with the gas and it flows into everything.No oil pressure whatsoever.In other words the oil just needs to get to where it needs to be volume is what we need to look at not oilpressure if
oil is the problem.I am leaning toward Jays theory of manufacturing defects specificly the huge pressure needed to press the crank together.I think that extraordinary amount is distorting the crank pin.A needle bearing such as we have needs a flat polished surface to ride on a crack or distortion will kill the bearing no matter how much oil is there.(bearing will shatter)then the heat occurs.I just dont know how to prove it.
I forgot about the Cams(duh)we do need oil pressure to get the oil to the cams lobes since oil needs to be lifted.
oil is the problem.I am leaning toward Jays theory of manufacturing defects specificly the huge pressure needed to press the crank together.I think that extraordinary amount is distorting the crank pin.A needle bearing such as we have needs a flat polished surface to ride on a crack or distortion will kill the bearing no matter how much oil is there.(bearing will shatter)then the heat occurs.I just dont know how to prove it.
I forgot about the Cams(duh)we do need oil pressure to get the oil to the cams lobes since oil needs to be lifted.
So realistically we don't have an oiling problem, but a manufacturing problem? How come other cranks can be rebuilt? I have had 250r cranks redone, rm, yz, cr etc. with no problems. If oil pressure isn't the problem, then why not add some bigger openings in places to allow the oil to get where it needs to go. I did notice some goulding (sp.?) on my stock wrist pin, how are we going to get more oil there?
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All those cranks you mention take half the pressure needed to assemble or disassemble the cannondale crank.I agree the wristpin area does need more oil but even though they gall I dont believe enough heat will ever build up there to seize it.Never heard of that although it sure makes it hard to pull the pin.
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I think they thought they were doing a good thing.Lots of cranks are welded after being put together to prevent them from coming out of sync or apart.There would never be a need for this with the cannondale crank.A redesigned normal crank would do the trick if this is the problem.Just have to prove this is the problem.It sure makes sense.If making a crank like they did made sense why does noone else make them like that?