WTH!! frame crack - pics

[alex90]

the lower motor mount on the 03 i recently bought is cracked clean thru!?.... i find it odd since the rest of the frame and mounts are as pristine as the day it rolled off the assembly line. this also is a low stress area of all the motor mounts and the rest are tight and to specs, so there is no way it twisted under load in the chassis, its an easy fix but im just scratching my head why that one of all the mounts?

its clean thru the entire mount and there is about a .16in of a gap between it and the frame rail it was formerly attached to

and to make it more strange it is nowhere near the weld where it cracked so it cant be just blamed on a simple weld failure... Shotty steel?. this blaster has never been abused and was a wife quad till i bought it and you can easily tell by looking at it since its just as pristine as my 06 if not more inside and out and judging from the looks of the piston and rings its only got about 50hrs on oem top end... this just baffles me, i wounder if i should contact Yamaha America and see what their explanation is :-/

 

[brandoz28]

usually the front ones are the ones that crack. that's fairly odd

 

[alex90]

usually the front ones are the ones that crack. that's fairly odd

EXACTLY!!!! just the fact that the swing-arm/motor conjunction mount is a few inches above there should absolutely be no stress there...

 

[sheeblast]

loose bolts? sh*tty weld job?

 

[alex90]

loose bolts? sh*tty weld job?

no i checked it all its all within spec and that weld is probably the cleanest on the whole damn frame, and it anyway cracked a good distance away from the weld so it cant be a result of under cut or pitting in the weld

 

[scotj77]

I think i know how that happened. mine was like that too at one point b4 i got it. i can tell it was fixed by a not so great welder. I think what causes that is the nut falling off the swinger bolt and not noticing it while ridding. when the bolt backs out far enough that it comes out of one side of the frame the sideways torque of the swinger breaks those welds and it will crack the crossmember on the swinger too. I put a cotter pin through the end of the threads on my pivot shaft to keep this from ever happening again. I have lost a couple nuts off of the pivot shaft while riding

 

[alex90]

hmmm the nut appears to have never been touched tho. i just now torqued it and its still got the white factory loctite. so its never loosened or been moved. i get what you are saying but i dont see any evidence of that occurring. the gap in the crack is pretty significant its like the bolt holes were off on the case or the mounts and they just forced it in at the factory and bolted it up and and time and vibration cracked it

 

[scotj77]

well, then i have no clue.

 

[alex90]

lol it really angers me, i think im going to contact Yamaha's corporate America office in California... maybe i can get us a recall and we all get new frames! yay or atleast for all 2003s haha

 

[scotj77]

mine's an 04 and the botom mount was broken just like the one in your second pic. pretty sure it was due to that nut fallin off bc i cracked my second swingarm the same way as the one that came on the quad when that nut fell off on the trail and i didn't notice

 

[alex90]

mine's an 04 and the botom mount was broken just like the one in your second pic. pretty sure it was due to that nut fallin off bc i cracked my second swingarm the same way as the one that came on the quad when that nut fell off on the trail and i didn't notice

hmm weird ill do more investigating to double check but it doesnt seem to be the case for mine, im gunna check again to see if i can see any stress or evidence from the situation that you explained.. this is a real bummer

 

[scotj77]

atleast it is completely fixable

 

[alex90]

very true but just sucks

 

[lasxgames]

very common with mx'rs,
http://www.blasterforum.com/suspension-14/frame-gusset-kit-9848/

http://www.blasterforum.com/suspension-14/frame-gusset-24188/
http://www.blasterforum.com/searchresults.php?cx=partner-pub-9438014176008015%3A9127094460&cof=FORID%3A9&q=gussets#863


broke my frame here on the track tripple. Only one to pull the tripple in my class.

 

[alex90]

nah the location of this crack has little to do with jumping. i can almost guarantee this blaster has seen nothing but a few feet of air due to the lack of fatigue in the normal stress points on the frame. and this thing is just my trail cruiser so if im gunna do gussets its going on my 06 first lol, thanks for the info dude.

 

[79 bronco]

Wow that sucks!!!! I have a dumb question, What does the bottom of the motor look like in the back by the crack???? Does it look like the motor hit a rock and got pushed up and cracked the mount upwards....:-/

 

[Blasterdude27]

My 03' cracked and obliterated the front engine mounts and frame..... but I've never seen that happen to the rear mounts.

That sucks man...

 

[alex90]

Wow that sucks!!!! I have a dumb question, What does the bottom of the motor look like in the back by the crack???? Does it look like the motor hit a rock and got pushed up and cracked the mount upwards....:-/

that was my initial thought. but she is clean of dents and nicks. its a real clean crack too not like stress crack where you can see fatiguing of the metal as it wore the stress into to crack.