BannedCR500Riders.com

had a rod break and it took a 1/2 x3/8 chunk out of the case where the crank fits in, should i try welding it or get a new one

hillclimbjim wrote:had a rod break and it took a 1/2 x3/8 chunk out of the case where the crank fits in, should i try welding it or get a new one

personally if i was still back home in PA. i wouldnt think twice about having the local welder guy weld it up.. he fixes all the coal truck beds and is a dirtbike rider himself .. has a huge shop and all the right tools.. he learned from his dad (R.I.P.) and knows his stuff..... really dont see why ya cant weld it up as long as the welder knows WTF hes doing...

if you dont have the ability to weld it or machine it back it can be a pain.

let me know what you need for it if you sell it

Post some pic's there are guys on here that will point you the right direction.

dont know how to post pics , dont look like its in to bad of a spot its up high

How the hell did you snap the rod?

hillclimbjim wrote:dont know how to post pics , dont look like its in to bad of a spot its up high

http://www.bannedcr500riders.com/board/ ... hp?t=10024

not even 1 hour on motor, dont know what happened,made the whole hillclimb season with it 17 races, 4 times a race

You runnin nitrous?

no c12, 32.1, mabey a bad rod, it was oem

13,000 rpm free rev when nitrous kicked in

4 bikes set up the same way with the same parts,all honda,

I just bought a bottom end with broken rod... the big end broke. and the whole rod is missing...
it only scored the cases a little, guess this guy got lucky.

I think guys run them till the big end bearings fail, when they pile up it spreads the big end into an oval an then the big journal cracks open....

just a theory I have....

probly defective i would guess. 3lb sand been through brits and rod held fine

This one broke on the intake / compression stroke, the bottom cases aren't bad but the head and cylinder apparently were wortheless...

I never have carnage issues like that all the years I have ridden

I cracked a honda rod on the big end and I didn't have a ton of time on it either. Adam found the crack during inspection.

we have repaired a cr 250 that holed the cases thru a dropped piston skirt needs to be a welder with some skills

seanmx57 wrote:I cracked a honda rod on the big end and I didn't have a ton of time on it either. Adam found the crack during inspection.

its wierd, thats the only rod i've ever seen cracked too. stil have pictures somewhere.

Welding the cases is no big deal, its having the ability to properly machine them back to working.

I bought a 1987 case on ebay for .01$ + 5$ freight
i blasted it, welded it, got the boring bar in it and sized it, then surfaced .002" off it to make sure it was strait. Its running excellent, was the first engine in my AF, sold it to bro for his conversion after i put my ported engine in.

its almost in the same spot and size

i had a set of cases where a broken rod had gone right through the bottom and made a huge whole on both halves. welded it up and worked great. looked funny from the outside the weld was a perfect heart shape.

it can be done.

weld it