my cbr had the crack in the frame so i thought i would post up the pics.

here is the original crack. not bad, but i didn't want it to get any worse.


so i used my dremel and cut a groove along the crack to clean it out and get good penetration on the weld


my friend at work TIG welded it for me.


here is a spare frame i have with massive cracking.

 

Your friend did a nice job on the weld.
The crack in the last frame above resembles the frame in my friends bike for length, but the crack extends from engine mount not upper spar.

 

weld um up no big deal the bikes have seen alot of years and some miles guessing thin metal that wasnt reinforced from factory weld it up and ride forever

 

Hey,

I'm a forensic engineer and I work as an Air Accident Investigator.

I've only flicked through the posts so I apologise but I'll add my two pence worth from 5 mins of looking at the pictures.

My bike is in the garage and I haven't looked at it this area intently so I don't know the condition of my bike at the moment.

If you notice all of the cracks appear on the welds just by the HAZ (Heat Affected Zone). I don't know what material the frames are made from and I do not know what the welding processes used were but there are a few explorable options.

The main points are:

The cracks seem to occur at curved sections which act as stress raisers .

There is corrosion with the cracks which indicates that they propagate over time, unfortunately corrosion destroys the fracture surface, removing the evidence.

From tripicana's fourth picture I would be inclined to think that it is a fatigue failure that is occuring. Fatigue propagates through cyclic motion which is generally caused by vibration (which all bikes do). As the failure seems to be on the same side as the side stand every time you rest the bike on the stand you are adding one extra cycle to the crack and it may also increase propagation. Also the crack on the left appears to be transgranular which is indicative of fatigue.

As for the failure initation, welding processes were not that great 20 years ago and its quite likely that the industrial processes used did not account for hydrogen embrittlement or porosity in the weld.

There doesn't seem to be an indication of stress corrosion cracking (I know there is corrosion and stress occuring but SCC tends to be an instant failure).

The important point is fatigue will continually propagate until the service loads on the component are too great and it will ultimately fail in overload. Overload happens quickly and I would recommend anyone who has a large crack to get it repaired A.S.A.P. - Also check your other welded areas just in case, including the other side of the frame, a £3 automotive inspection mirror is all you would need.


I wouldn't want someone out there to get hurt due to their bike failing on them.

But don't take this as expert advice, I would need to physically see the components and investigate them myself before I could actually give a true reason why the cracks are occuring.

I've just seen how old this post is and I've just chucked out a load of information that people may not be bothered about. If anybody is worried about a crack they can always contact me.

 

well if popular opinion is that wheelie damage, thankfully mine hasnt been.....i saw this thread, at about midnight....ran out with a flashlight and checked my frame.....thankfully no crack

 

i'm thinking it has more to do with the sidestand. or a combination of sidestand, and loose mounting bolts. i think the steering stem would take the brunt of wheelies.

i've reinspected my welded crack. no signs of more cracking.

 

im tending to agree with that, my first ninja was beat on wicked bad, the kid bragged about how easy it would yank the front end up, and that ones steering tabs were a little damaged and there were stress cracks in the frame's paint but none in the frame, it was only to teach me how to handle a sportbike and see if i could grapple working on em, which both worked out good, but if i had been turned on to hurricanes sooner, i would have owned less bikes

 

I find it funny that people think wheelies are the cause, and that it couldn't be a flawed design or manufacturing process in their most beloved bike lol. Wheelies are something you see a lot of on the internets, cause it makes good viral video, but IRL the vast majority of bikes are not doing any wheelies. So I doubt all of these cases can be attributed to wheelies.
It's like the cracking frame on the 05-06 and 07-08 gsxr's issue. Suzuki tried to blame it on wheelies/rider abuse at first. However, cracks were discovered in far too many and too new of bikes for that to be the case, so they had to do a recall and drill frames and install plates.
People want to blame wheelies cause that's the easy fix, just don't do wheelies, and so they can feel good about themselves for not doing wheelies and believe they are immune to this problem. Having to accept the fact that it's the design/manufacture of the bike means huge lengths to correct the problem, which is hard to swallow. As evidenced by some peoples refusal to inspect their own frame for fear of what they might find?? WOW

If it's taken that long (20 years) for stress cracks to show up in these frames, I don't consider that to be too bad, although obviously an issue. I'd imagine it's not easy to foresee how long something will hold up when you're artificially stress testing a part for longevity. In Suzuki's case though, I think they neglected it entirely for cases to show up in less that 1 to a few years. If they would have accepted that it may be a design/manufacturing process problem sooner, instead of choosing to blame the riders and wheelies, maybe they wouldn't have continued to produce cracking frames for as many years as they did, 4, 05-08. They could have stopped it at 2 or 3.

Here's a pic of a suzuki factory recalled frame fix


If they are able to make mistakes like that this day in age it's not so far fetched to believe they could have made a similar mistake way back when which took a good 10-20 years to show up. I'm sure the hurricane frame being steel helped.

 

The opinion that Cuzy offered agrees with the "metal fatigue" theory I put out a long time ago. So with theories ranging from wheelies to kick stands to high frequency buzz, you can add it to the pile. So like I stated earlier my main intention (check the dates of the posts) was to bump the post back to the top where most people look instead of page 15.
I believe a cracked frame represents a real concern for those of use who continue to ride this older model. And my original post has been bumped by myself and others who wanted to keep this readily accessible.

 

hey guys :-)


Be nice to each other!! ;-)

I also have a proposition for you :-)


Jules (your **** bish mod)