Author Topic: Small end bearing sizes  (Read 1070 times)

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Offline till1mk1rs

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Small end bearing sizes
« on: April 17, 2014, 12:57:55 AM »
Can anyone confirm the small end needle roller bearing size? I have taken the old one out of my bike and the sizes are 18x23x22mm but the one the bike shop has sent me is 18x22x23mm I have done a bit of research on google etc but can only find a part number not sizes.
If anyone has the measurements it would be good to know if my con rod has been machined at some point.

Cheers

Offline cabmkr

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Re: Small end bearing sizes
« Reply #1 on: April 17, 2014, 10:37:06 AM »
I don't know exactly for the 425 but a 78 IT400 stock rod has a 18 ID and 22 od bearing but I put in new rod from an 89 or so YZ250 which was the same length but has a 18 ID and a 23 OD bearing

Chris   
Bikes.....Lost count!

Offline 2fITy.J

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Re: Small end bearing sizes
« Reply #2 on: April 17, 2014, 03:41:15 PM »
That happened to me years and years ago....circa 76 ish....anyway, turns out the conrod was an aftermarket one put in by the PO....wrist pin was a different one too...

New piston and top end bearing were useless to me without a full teardown.



Cheers,
Chris.
A bike in the bush is worth two in the shed!

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Offline till1mk1rs

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Re: Small end bearing sizes
« Reply #3 on: April 17, 2014, 07:16:07 PM »
Thats interesting to know.  I have checked and my IT has a genuine conrod fitted but it could be out of something else maybe?

Offline cabmkr

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Re: Small end bearing sizes
« Reply #4 on: April 18, 2014, 07:28:08 AM »
What's the code on the rod?

I have used this link for referencing con rods

http://www.mitaka.co.uk/MDP.htm    CONROD KIT DIMENTIONS

Chris
Bikes.....Lost count!

Offline Martin I Henry

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Re: Small end bearing sizes
« Reply #5 on: April 20, 2014, 10:36:38 PM »
IT425 small end bearing here :

http://www.ebay.co.uk/itm/121323052744?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

My IT425G and parts are in storage right now, so I can't take any measurements.

Cheers,

Dave R.

Offline till1mk1rs

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Re: Small end bearing sizes
« Reply #6 on: May 01, 2014, 03:49:13 PM »
Sorry got my measurements wrong. I have done some more research and the IT 425 was fitted with a 18x22x22 small end but for some reason my IT 425 has a 18x23x22. I think the old girl must have had a different crank put in at some point. Had to get a bearing from my local bearing dealer in the end  :)