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Discussion Starter · #1 ·
Hi I took the pistons off the connecting rods .. one of the rods has too much play and has scrape marks on the side .. I know I have to split case now I have the Clymer manual. but not clear what to do ... is there a bearing that I need to replace? is it call the connecting rod bearing? would appreciate some advice .. I have no previous experience.... thanks
 

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The rods in this engine are installed onto the crank as an assembly. The crank is pressed together. Typically the rods cannot be changed as part of normal maintenance. It takes a specialist to do the job. It is possible to make a bushing for the rod, but is is a lot of work. The best thing to do is find a good crank. I had this problem on mu '72 CB450.
 

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Discussion Starter · #5 ·
not sure if this is the appropriate place... any members got a crank to sell... my bike is a K2 vin 3015363 don't know if that makes a difference .There is one on eBay at the moment in the US but it doesn't look good ( rusty) any Aussies got one to sell ?... worth a try ... I will get it to go.
 

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not sure if this is the appropriate place... any members got a crank to sell... my bike is a K2 vin 3015363 don't know if that makes a difference .There is one on eBay at the moment in the US but it doesn't look good ( rusty) any Aussies got one to sell ?... worth a try ... I will get it to go.

Doesn't matter - any 5-speed crank will work.
 

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not sure if this is the appropriate place... any members got a crank to sell... my bike is a K2 vin 3015363 don't know if that makes a difference .There is one on eBay at the moment in the US but it doesn't look good ( rusty) any Aussies got one to sell ?... worth a try ... I will get it to go.


I have a couple of cranks in the shed, not sure how good they are -- will check, but not till the weekend if you can wait that long? Allan

Just what is wrong with your crank, and how did you decide it was buggered?
 
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Discussion Starter · #9 ·
thanks everyone for you answers 450roo I am a mechanical novice but one connecting rod is tight hardly any movement up or down or sideways.. the second connecting rod is totally different ..heaps of movement and one side of the rod has been scraping on something, looks like about 4inches of it has been hit with a file. I reckon that constitutes buggered... I have called and emailed a few vintage Japanese bike wreckers but seems it is different here than the USA. to get parts . I bought the bike which hadn't run for 25years the pistons were stuck but I think I know why the bike was parked (noise) if you have got a 5 speed crank I can wait until the weekend .. in the mean time I will
 

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thanks everyone for you answers 450roo I am a mechanical novice but one connecting rod is tight hardly any movement up or down or sideways.. the second connecting rod is totally different ..heaps of movement and one side of the rod has been scraping on something, looks like about 4inches of it has been hit with a file. I reckon that constitutes buggered... I have called and emailed a few vintage Japanese bike wreckers but seems it is different here than the USA. to get parts . I bought the bike which hadn't run for 25years the pistons were stuck but I think I know why the bike was parked (noise) if you have got a 5 speed crank I can wait until the weekend .. in the mean time I will

OK, in the mean time you should pull the cases apart clean everything and look for other problems. See ya!
 

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I managed to get out to the shed and I have an exceptionally good crank from an early 5 speed 450, has all the rollers and outer bearings the only thing missing are the locating pins on the outer bearings.
Can send pictures if you wish. I would have to ask $200- for it.
I have an other not quit as good but quite usable you can have for $150-
If you give me your address I will find out the cost of freight for you. Allan
 

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I have had a look in the shed and I have two usable cranks. One absolutely excellent low mileage crank complete with all rollers and outer bearings the only thing missing are the outer bearing locating pins. Will have to ask $200- for this one.
The other crank is not as good as the first but quite usable you can have for $150-
If you let me know your address I can get the cost of freight to Sydney for you. Allan
Might be easier if you email me at <[email protected]>
 

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Discussion Starter · #14 ·
thanks heaps 450roo I will buy the better one for $200 also I sent out many emails to vintage wreckers and made lots of calls and have sourced a complete motor with compression . plan being to put this motor in bike and rebuild the old one ...450roo have sent email to private message
 

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Kanga,
I made the mistake of buying a second motor. It was a waste of time and money. I wound up selling it for less than I paid for it. I know you haven't solicited advice but sometimes I cannot help myself. I would recommend using your money to acquire serviceable parts that are within factory specification. This would include fresh cams, followers, pistons and rings and a full valve job. The more you can do here the better bike you will have in the future. Used engines are like used bikes. It is not unusual to discover a major problem that took the bike off the road. There is always a reason the bike was not used.
 

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Discussion Starter · #16 ·
Thanks Jim I feel you are right but I am going to take a chance . i wouldn't if it was too expensive, and I don't really know the state of the motor except that it has compression . I am getting it quite cheap at $600 because the guy I got the original bike from was selling it for $1000 ...so he if giving me a break because he thought I would have to rebuild the top but was surprised at the state of the crank. I am going to buy a crank from 450roo as well .
I suppose I could have bought a bike going but wanted a challenged and learn something . i was surprised
at myself that I got the motor out and processed to getting the wrist pins out . it is a bit of a shame about the crank but I am not deterred .. appreciate everyones help
 
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