OzVMX Forum

Clubroom => Tech Talk => Topic started by: maxi81 on December 22, 2010, 07:11:31 pm

Title: RM crankshaft
Post by: maxi81 on December 22, 2010, 07:11:31 pm
Is this fixable??

(http://i1033.photobucket.com/albums/a420/motoguy81/DSC00286.jpg)
Title: Re: RM crankshaft
Post by: Davey Crocket on December 22, 2010, 07:14:16 pm
What model RM?...may be cheaper to get a secondhand one or a new crank half.
Title: Re: RM crankshaft
Post by: maxi81 on December 22, 2010, 07:21:33 pm
RM 400T. I've found it a bit hard to source a second one
Title: Re: RM crankshaft
Post by: DR on December 22, 2010, 07:23:11 pm
If it were mine it'd be tossed in the scrap bin ;)

No matter what model RM I'd reckon another crank would be the way to go. If you can't get one locally then the US maybe the go..will see what I can hunt up ;)
Title: Re: RM crankshaft
Post by: maxi81 on December 22, 2010, 07:25:38 pm
Thanks for that Doc
Title: Re: RM crankshaft
Post by: DR on December 22, 2010, 07:28:00 pm
http://cgi.ebay.com/ebaymotors/1980-Suzuki-RM400-RM465-Crank-Shaft-Conrod-Complete-_W0QQcmdZViewItemQQhashZitem2c5530e741QQitemZ190407829313QQptZMotorcyclesQ5fPartsQ5fAccessories#ht_500wt_747 (http://cgi.ebay.com/ebaymotors/1980-Suzuki-RM400-RM465-Crank-Shaft-Conrod-Complete-_W0QQcmdZViewItemQQhashZitem2c5530e741QQitemZ190407829313QQptZMotorcyclesQ5fPartsQ5fAccessories#ht_500wt_747)

there seems to be a few on eBay US

http://shop.ebay.com.au/?_from=R40&_trksid=p3907.m570.l1313&_nkw=rm400+crank&_sacat=See-All-Categories (http://shop.ebay.com.au/?_from=R40&_trksid=p3907.m570.l1313&_nkw=rm400+crank&_sacat=See-All-Categories)
Title: Re: RM crankshaft
Post by: evo550 on December 22, 2010, 07:36:57 pm
What happened to that  ???
Title: Re: RM crankshaft
Post by: maxi81 on December 22, 2010, 07:37:50 pm
Do you think they look okay? I''m no expert
Title: Re: RM crankshaft
Post by: maxi81 on December 22, 2010, 07:40:03 pm
Crank gear was welded onto crank for some reason. It was my dad's bike.
Title: Re: RM crankshaft
Post by: LWC82PE on December 22, 2010, 07:55:11 pm
Quote
Is this fixable??


YES but only if you cant get another one. Try to get another second hand one first. If you cant then any decent machinst/crank repairer can fix that.
Title: Re: RM crankshaft
Post by: oldfart on December 22, 2010, 08:37:18 pm
Typical .... nut has come loose on primary drive , gear was able to chatter away on key way,   and this is the end result.
Title: Re: RM crankshaft
Post by: holeshot buddy on December 22, 2010, 08:48:05 pm
common problem on big bore suzys
Title: Re: RM crankshaft
Post by: Lozza on December 22, 2010, 09:09:43 pm
It is quite 'easily' fixed. Those Swedish $hitters Huskervarna's have press in ignition tapers probably for similar reasons if that part ever gets damaged.

To fix it a new primary shaft end would be machined and heat treated and final ground to size. then the shaft on the crank web would be cut off and then a hole EDM wire cut or CNC machined out. The 2 components then pressed together.

Do not let anyone weld another repair section onto the existing crank as that will end in tears.
Title: Re: RM crankshaft
Post by: LWC82PE on December 22, 2010, 10:57:29 pm
Quote
To fix it a new primary shaft end would be machined and heat treated and final ground to size. then the shaft on the crank web would be cut off and then a hole EDM wire cut or CNC machined out. The 2 components then pressed together.


Agree
Title: Re: RM crankshaft
Post by: DR on December 22, 2010, 11:58:24 pm
Sounds like a lot of trouble to repair when another crank is available..it's not like it's an RN400 crank :-\

This crank below 'appears' to be from a 1979 RM400N going by the numbers supplied. If correct it will bolt straight into the '80 400T. The seller say's no up and down play but there is lateral movement. This lateral movement he mentions is probably quite normal and it may well be useable as is but rebuilding it would be the go especially if you can get it sent over for a reasonable price in the first place. I hate to recommend anything as it always seems to turn around and bite me on the arse but eh..that's the one I'd be looking at. Email the seller and ask the questions ;)

http://cgi.ebay.com/ebaymotors/SUZUKI-RM400-RM-400-ENGINE-CRANK-SHAFT-CON-ROD-_W0QQcmdZViewItemQQhashZitem3eedd3425fQQitemZ270278017631QQptZMotorcyclesQ5fPartsQ5fAccessories (http://cgi.ebay.com/ebaymotors/SUZUKI-RM400-RM-400-ENGINE-CRANK-SHAFT-CON-ROD-_W0QQcmdZViewItemQQhashZitem3eedd3425fQQitemZ270278017631QQptZMotorcyclesQ5fPartsQ5fAccessories)

there is another further down the page that lists a crank for $100 but it lists it for both the RM400 and RM465 which are not interchangeable so I've no idea what he's on about to start with ??? might be an okay thing too but he needs to dicide if it is RM400 or RM465 ;)


Title: Re: RM crankshaft
Post by: Lozza on December 23, 2010, 12:15:17 am
That rod could do with an upgrade, going to need a new primary gear also >:(
Title: Re: RM crankshaft
Post by: DR on December 23, 2010, 07:37:28 am
RM400N RM400T RM465X RM465Z '79='82 all share the same primary drive gear (26t) there's a few on ebay US ;)

http://cgi.ebay.com/ebaymotors/RM400-SUZUKI-1980-RM-400-80-PRIMARY-CRANK-GEAR-_W0QQcmdZViewItemQQhashZitem48312150dfQQitemZ310061912287QQptZMotorcyclesQ5fPartsQ5fAccessories#ht_3222wt_728 (http://cgi.ebay.com/ebaymotors/RM400-SUZUKI-1980-RM-400-80-PRIMARY-CRANK-GEAR-_W0QQcmdZViewItemQQhashZitem48312150dfQQitemZ310061912287QQptZMotorcyclesQ5fPartsQ5fAccessories#ht_3222wt_728)
Title: Re: RM crankshaft
Post by: maxi81 on December 23, 2010, 02:01:08 pm
Thanks to everyone who has replied. Much appreciated