Welding on a crank?

[scumdog]

OK so i managed to get pictures, Pic 1&2

Attachment 291957

Attachment 291958

I just cleaned it with methylated spirits, Ill try the knead it steel now

Grab some J-B Weld and build up the 'bad' area then sand it down finishing with 1200 grit.

[gammaguy]

http://www.ebay.com/itm/94-1994-rmx2...427bad&vxp=mtr

[Brian d marge]

A bit far !!! , fk u were pissed as bro !

yes they can be welded up and re machined , DO talk to a vintage repair shop OR an old fart who chain smokes and can find his spectacles

the metal isnt flash on those , but the stresses are right at the root /end of your cut ( there are up and down forces and clockwise anti clockwise and hertzian or where ever you created the stress raiser ,, and you do not want to make that brittle by incorrect temp control or it will shear at the base of the taper ,, not immediately but it will happen

sorry I can give a bit more detail but must take boys to Judo

Stephen

[Kickaha]

PM Swarfie, he's a right clever bastard and will be able to point you in the right direction

[pete-blen]

I wouldn't think twice about welding that...
use a tool post grinder in a lathe to regrind the tapper as
you can set the compound angle to match the crank tapper..

Even though they are out of fashion these days.. I would use a arc welder
Rods.. common old low hydrogen.. Was all we use to use on the TZ crank pins
to stop the cranks going out of true...

remove the cut section to ensure theres no voids in the weld..

really it all pretty easy..

[jonbuoy]

It will be in compression so JB might work but will always be a bodge. You would have to split the crank for welding/braizing. I'm sure any crank that gets welded must distort a little bit, when a machine shop does it they will check/straighten the crank afterwards anyway so not a problem in those cases.

[matrox02]

http://www.ebay.com/itm/94-1994-rmx2...427bad&vxp=mtr

I wish that did fit, only the 89 to 92 l m n models fit, thats a s t 94 and have differant everything,

Otherwise ill see if the knead it steel stuff just falls off or not during the day if not then ill file down to shape and what happens there, if it does fall off ill be on more of a look our for an old boy sitting in the back of an old shop

[Brian d marge]

I wish that did fit, only the 89 to 92 l m n models fit, thats a s t 94 and have differant everything,

Otherwise ill see if the knead it steel stuff just falls off or not during the day if not then ill file down to shape and what happens there, if it does fall off ill be on more of a look our for an old boy sitting in the back of an old shop

The joint is a taper , or an interference fit,

Think of it as yer cock going into a tight young virgin , shes going clamp down on your tool good and tight,

now forty years later ( or in this case half a ton of JB weld , with lesser mechanical properties ) your cock aint as firm and that tight young hole wouldnt be stretched as much , and your cock aint clamped as much as it was back in the day ,

So after a while it may slip out , or in this case you will find it hard to keep your flywheel from coming loose ( it will just shear the key and spin )

you might be in luck , as it is lightly loaded and wouldnt need much of a taper to hold it , but by the looks of that photo my guess its touch and go

Im not familiar with Suzuki pt numbers , but many of hondas parts are shared across quite a few models and even then all you want is that shaft ! are you sure nothing else can be found that will work?

Stephen

[matrox02]

The joint is a taper , or an interference fit,

Think of it as yer cock going into a tight young virgin , shes going clamp down on your tool good and tight,

now forty years later ( or in this case half a ton of JB weld , with lesser mechanical properties ) your cock aint as firm and that tight young hole wouldnt be stretched as much , and your cock aint clamped as much as it was back in the day ,

So after a while it may slip out , or in this case you will find it hard to keep your flywheel from coming loose ( it will just shear the key and spin )

you might be in luck , as it is lightly loaded and wouldnt need much of a taper to hold it , but by the looks of that photo my guess its touch and go

Im not familiar with Suzuki pt numbers , but many of hondas parts are shared across quite a few models and even then all you want is that shaft ! are you sure nothing else can be found that will work?

Stephen

yeah sadly, not with out changing alot more than just the bearings and seals, even the RM250 motors are different in many ways, seams as thought he only truely cross compatible parts are the barrels and heads

[matrox02]

So i found a machinist/metal refurbisher who is willing to do the job, it will however require that i have a flywheel to do test fitting, he says that metal spraying and then balancing the shaft is what he will do and he will do it for 200 cash so i think ill do that, just need to find a Flywheel for my bike now

[matrox02]

So, I needed a flywheel and nut to get the crank repaired, I call Suzuki and tell them i need a full stator assembly and a new flywheel/rotor, they get back to me with a quote of 780 bucks for the stator ( Must be gold plated! ) and the Rotor at just shy of 500! ( must be gold plated too! ) Im glad Ebay exists though as a New after market Fly wheel stator assembly and coil-cdi and a bunch of other things for 800 ndz all up shipped from America and thats including Duty costs.. I can only say that im stoked!, next is Bearings/seals and gaskets and rear shock rebuild and im sorted!

[george formby]

Did you go for a quote from JP-parts?

[speights_bud]

If it wasnt for the price I would have recommended Laser welding it up, we send our parts from Napier to Auckland to have a Chap up there do it, lots of our stuff is very finicky (toolmaking boo boos) but the heat put into the crank would be very minimal.

[matrox02]

Did you go for a quote from JP-parts?

Yeah I emailed them with their responce being " Not made anymore, cannot help" so.. maybe for other parts.. but not the webs :S

[matrox02]

If it wasnt for the price I would have recommended Laser welding it up, we send our parts from Napier to Auckland to have a Chap up there do it, lots of our stuff is very finicky (toolmaking boo boos) but the heat put into the crank would be very minimal.

what sort of prices are they? Im having my crank fixed up for 200 cash thats metal sprayed and machined ( I hope they dont fill the key way in! )