April 8th, 2017, 08:04 PM | #41 |
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Name: David
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so a stupid question, what would the size be that I tell them to grind it to? The service manual doesn't seem to specify the different bearing sizes. Thanks for all the advice!
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April 8th, 2017, 09:18 PM | #42 | |
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Name: Bill
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eBay
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April 8th, 2017, 10:02 PM | #43 | |
Guy Who Enjoys Riding
Name: Jim
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Any decent automotive machine shop is very familiar with the stuff I'm saying, so they should be able to help answer your questions. You just have to find out what undersized bearings are available for our 250s. Or buy an eBay engine. |
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April 9th, 2017, 05:01 AM | #44 |
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Name: Julius Michael
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if your planning to fix the crank , ask the machinist what might be the cause of failure , show him the bearings and the journal , then go check the engine it could be debris in the oil , clogged oil passageways or lack of oil/oil filter etc , you must first fix the underlying cause of the bearing failure or else this repaired crank life may suffer the same fate again
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April 9th, 2017, 02:24 PM | #45 |
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Name: David
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I will take it to a machine shop and see what they say. None of the bearings are discolored , the oil and filter were new. So no idea if anything broke, but visually inspecting things everything looks ok. Only concern is the failed bearing connecting rod cap is snug and gotta really pull it to get it off. Make me wonder if it might be a little twisted or tweaked.
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April 9th, 2017, 02:37 PM | #46 | |
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April 9th, 2017, 02:42 PM | #47 |
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Name: David
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based one what I posted earlier, did I read the manual correctly in terms of which part # I need for the connecting rod bearing replacement?
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April 9th, 2017, 06:55 PM | #48 | |
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Quote:
example your crank big end journal was 30.00mm your stock bearing was a brown color coded so its 1.480mm-1.485mm thick, the machinist needs to remove about 0.005mm - 0.010mm of material from the crank journal. so the bearing you need will be the next color code black(oversize) with the size of 1.485mm-1.490mm . After that, to further confirm this you need to use plastigage to measure the bearing to journal clearance when the conrod caps are torqued to spec 27 N-m(20 ft/lb). The acceptable journal to bearing clearance is 0.031mm-0.059mm |
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April 9th, 2017, 06:58 PM | #49 | |
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Name: David
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makes sense, I have plastigauge from my last 250 rebuild. 20ft on the conrod caps? The ones I took off were definitely not at 20, they took quite a bit of strength for me to bust them loose. I wonder if thats why the one failed? connrod torqued down too tightly? |
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April 9th, 2017, 07:04 PM | #50 |
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it could be , too much torque will cause the bearing to bend and the clearance will change , you can inspect it by looking in the surface of the journal and the bearing.
this will give you some clues: http://www.tribology.co.uk/services/...ring-failures/ |
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April 9th, 2017, 07:11 PM | #51 |
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Name: Julius Michael
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when torquing the con rod caps you need the area to be oiled up or else it will read different torque values and might destroy your engine
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April 9th, 2017, 10:14 PM | #52 |
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Name: David
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here is a pic of the good conn-rod bearing
http://imgur.com/PMeH86N and here is a pic of the failed one, looks like the one in the pic that says Causes: Inadequate bearing clearance, overheating, insufficient oil supply, excessive load, or operation with a non-cylindrical journal http://imgur.com/NwLwmrO |
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April 9th, 2017, 10:22 PM | #53 | |
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did your oil looks like this and smell like rotten eggs? i believe the con rod caps tightness even without the bolts are correct just notice the teeth o the bolt where the caps sits its meant to be tight if in doubt you can replace the con rod bolts the bearings are cheap we got brand new bearings here in the philippines for around 2$(92 pesos) genuine from kawasaki assembly plant |
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April 9th, 2017, 10:33 PM | #54 | |
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Name: David
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http://imgur.com/tPGi5GR http://imgur.com/XG0KT7a looks pretty think and sludgy to me. |
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April 9th, 2017, 10:48 PM | #55 |
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mine was changed too before we got it but the metal particles remained at the bottom there was no black thick oil but the smell was of that of rotten eggs near the broken bearings, were not sure about the cause but heres my theory the bike had no oil filter in it particles may got into the bearing surfaces and destroyed the oil film
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April 9th, 2017, 10:53 PM | #56 | |
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April 9th, 2017, 11:33 PM | #57 | |
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April 9th, 2017, 11:34 PM | #58 |
ninjette.org guru
Name: David
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the bearings I looked up are like $12 a set. where are you getting them that cheap?
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April 10th, 2017, 12:12 AM | #59 | |
ninjette.org guru
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Quote:
http://kawasaki.ph/commuter/about-us.php |
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April 10th, 2017, 06:50 AM | #60 |
Guy Who Enjoys Riding
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I'm not so sure how good that good bearing looks. It has some scratches and other marks that I'm not used to seeing on good used bearing inserts. The photo may be making it look worse than it really is, but it might be worth showing the guys in the machine shop.
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April 12th, 2017, 09:23 AM | #61 |
ninjette.org guru
Name: David
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so I took the crank to a machine shop. Its 5 thousandths below service limit as it is. So looks like I will be looking for either a new crank, and if cheap enough a new motor and keep this one for parts.
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