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Discussion Starter #21
So guys I made my final decision about the magnetic con rod kit....
Do nothing, Lol
I pulled the rotor off my YZ125 bikesaw.
The compass needle spins like crazy against the crank stub.
 

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I would always de-magnetize steel engine parts, specially bearings, needles, rollers. It is also standard and recommended practice for high performance bearings used in Jet Turbine engines...FYI

To big deal to de-mag :)

Carlos
 

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Discussion Starter #23
I would always de-magnetize steel engine parts, specially bearings, needles, rollers. It is also standard and recommended practice for high performance bearings used in Jet Turbine engines...FYI

To big deal to de-mag :)

Carlos
Thanks Carlos
But if the ignition magnetizes the crankshaft anyways, does it really matter?
 

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Discussion Starter #24
@acecarlos .
I'm being told by many enthusiasts all over the world not to rebuild my crank with the Japanese made PRO-X 1978-2001 CR250 connecting rod kit. I thought they were the best aftermarket option on the market.

So should I go with OEM rod and pieces or go with the NOS OEM 1983 CR250R crankshaft???
 

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@acecarlos .
I'm being told by many enthusiasts all over the world not to rebuild my crank with the Japanese made PRO-X 1978-2001 CR250 connecting rod kit. I thought they were the best aftermarket option on the market.

So should I go with OEM rod and pieces or go with the NOS OEM 1983 CR250R crankshaft???
Don't know why; the ProX rods we use and sell all come from Japan, my understanding is they are made at the same Factory the Honda OEM rods originated from. We also use Honda OEM Rods from old stock and some that are still available as new OEM.

I wouldn’t put a lot of validity to what “everyone” has to say; unfortunately, a lot of advice given comes from hearsay, make your own decisions based on experience and sound judgement. That’s my approach…:)

As an FYI; I have rebuilt dozens and dozens of OEM & HR crankshafts using the ProX Rods, and never had one fail to date.

Carlos
 

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Discussion Starter #26
Don't know why; the ProX rods we use and sell all come from Japan, my understanding is they are made at the same Factory the Honda OEM rods originated from. We also use Honda OEM Rods from old stock and some that are still available as new OEM.

I wouldn’t put a lot of validity to what “everyone” has to say; unfortunately, a lot of advice given comes from hearsay, make your own decisions based on experience and sound judgement. That’s my approach…:)

As an FYI; I have rebuilt dozens and dozens of OEM & HR crankshafts using the ProX Rods, and never had one fail to date.

Carlos
Thanks Carlos for your reply.
Yes lots of hearsay out there.
I'm seriously thinking of ordering the NOS OEM 1983 Honda CR250 crankshaft from Texas.
Who knows maybe this crank was dropped on the floor and is out of alignment but all the bearing surfaces etc. are to spec.
Not having the tin can covers it would be easy enough to re align if it was dropped.
 

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Discussion Starter #27 (Edited)
@acecarlos and @matuus
64482
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My NOS OEM '83 CR250R was shipped out this morning! Probably the last one in existence.
No more worries about rebuilding a wore out crank with a aftermarket rod kit and Loctite 680 on the journals to retain the pair of OEM main bearings.
Interesting Honda switched to the full circle tin can covered crank the following year in '84 when Yamaha retained the similar '83 Honda sculpted web TZ125 crank in 1995. A 125 engine putting out 44 bhp stock.
 

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@acecarlos and @matuus
View attachment 64482 View attachment 64483 View attachment 64484 View attachment 64481

My NOS OEM '83 CR250R was shipped out this morning! Probably the last one in existence.
No more worries about rebuilding a wore out crank with a aftermarket rod kit and Loctite 680 on the journals to retain the pair of OEM main bearings.
Interesting Honda switched to the full circle tin can covered crank the following year in '84 when Yamaha retained the similar '83 Honda sculpted web TZ125 crank in 1995. A 125 engine putting out 44 bhp stock.
Nice....-)

As far as Honda and Tin covered crankshafts, here is one I bet most don't know. Honda went to Tins for two reasons I was told back in 85-86. One is to stuff the cases, the other was to validate their IP. Honda had various Patents on 2 strokes, one included Tins. In order to add 'strength to their IP, they used Tins. This would keep others from being able to copy other aspects of their 2-stroke technology.

Carlos
 

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Discussion Starter #29
Nice....-)

As far as Honda and Tin covered crankshafts, here is one I bet most don't know. Honda went to Tins for two reasons I was told back in 85-86. One is to stuff the cases, the other was to validate their IP. Honda had various Patents on 2 strokes, one included Tins. In order to add 'strength to their IP, they used Tins. This would keep others from being able to copy other aspects of their 2-stroke technology.

Carlos
That's interesting. Thanks
It seems today with our modern intake reed systems and superior tuned exhaust technology stuffing the crankcases is no longer so important.

I was going to give you a phone call the other day and ask if I could get my crankshaft shipper in Texas to ship the crank directly to you to check it over.
But my tree service and family life is keeping me ragged. Has been one of my busiest tree season ever.
 

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I still believe correctly stuffing the cases is crucial...

You can always send the crankshaft to BDT, I can fully inspect between centers, and check balance. I can video the results for you if you like.

Always curious to see what’s out there.:)

Carlos
 

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Discussion Starter #31
Thanks for the offer Carlos.
The ebay seller reassured me that he bought the NOS crank from a honda dealer going out of business and it was always in its original factory packaging.
Knowing it value he never put it up for bid on ebay.
Took him a few years to sell it and I'm the lucky buyer.
 

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Discussion Starter #32
acecarlos my crank is stuck in Chicago distributing center since Aug 28 may be there for weeks to come. Big back log going on.
I should have had it shipped to your shop.
I had some tree service equipment parts ordered and shipped from Woodland, California last week , took less then 5 days to get to my door.
 
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