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View Full Version : Need Help! Frame break on motorcycle from the manufacturer



janefox
03-27-2008, 10:02 PM
Hi everybody! Thanks for taking me in. I really need some professional help on this. I would really appreciate everyone opinion.

Take a look at these pictures and tell me what you think. They are informing me that it can be "temporarily" repaired and ridden with the temporary weld. I don't think so. In my opinion it should have never been welded like this in the first place, but I'm not expert on welding that's why I need all of you.
Please tell me what you think. I would really like to hear your imput on this.
Let me know if the pictures came through.
Thanks so much!
-jane

Me2
03-28-2008, 03:55 AM
Ok, first question, what is the material spec?
If it’s a chrome moly steel you just can't fly into it.
To do a high quality job tig welding with proper preparation is required.
A matching or as close as possible matching filler material must be used.
Pre-heating is also required along with a specific rate of cooling.
A qualified welder should be doing this work with if possible a pre-qual weld done and inspected by x-ray or etching for quality assurance before proceeding.
Ripping into it with a "temporary weld" is taking your life into your hands.
Doing this can make the situation worse.
Get the opinion of a certified professional automotive engineer before proceeding giving you all the required certifications for insurance purposes as required.
In the mean time don’t ride it until it’s repaired professionally, your life and that of other road uses is at risk not to mention the liability when your insurance company find out and leave with a life enduring financial legacy.

ThatguyDave
03-28-2008, 01:14 PM
I agree with Me2, this isn't something which is wise to just tack back together with a mig welder at a muffler shop. A descent tig weld reinforced with a reasonable gusset is probably sufficient to safely connect the damaged tubing back together.

However.... Such a repair at best would only be as strong as the frame was prior to whatever incident broke it in the first place. Assuming this break occured as a result of metal fatigue incurred during normal use, even a perfect repair will not result in a sufficiently strong frame. Steel tube structures are very good at dissipating energy and steel's fatigue life is far superior to that of the aluminum so commonly used in production motorcycle frames. However, these sorry underengineered chopper frames, particularly hardtail frames, are so poorly concieved that breaks like this one are simply inevitable. I have in the past modified stock Harly frames and swingarms and while they were poorly triangulated and designed mainly for ease of assembly, they were made of very thick steel tubing welded with deep penetration (abet very sloppy) welds to massive cast steel lugs. The thin tubes used in many aftermarket ones like your are simply not up to the extreme stesses placed upon them. Who made this frame anyway?

mactec54
03-28-2008, 02:09 PM
Hi janefox
This is not a big deal as the others have said in dirt track racing it is common to
cut that bottom tube to get more flex in the frame which can add more traction.

In your case it has not been welded very well if you look at it closely you will see that it has a sleeve inside the tube which is telling you it was a join and not a brake of the tube
when they welded it and ground/sanded the weld there was not much weld left.

The weld may have been forgotten as well & the paint would have covered it

This should be on who ever built the frame & is not a big deal to reweld most of the tubing used is a seamless high quality steel not crome moly so makes for welding a little
easer Tig or mig will work just fine with good prep it would be as strong as tube its self

Enjoy your ride

Geof
03-28-2008, 02:17 PM
.... reinforced with a reasonable gusset is probably sufficient to safely connect the damaged tubing back together.

However.... Such a repair at best would only be as strong as the frame was prior to whatever incident broke it in the first place.....

Definitely get proper experienced advice. My advice is to toss the frame and replace it with a new one. Perhaps you should get legal advise because motorcycle frames should not break no matter what; you may have a claim against the manufacturer.

Regarding repair suggestions any repair will be weaker than the original frame. Adding a gusset or anything like that may be worse than just welding. The gusset is an abrupt change in cross-sectional area where it welds to the tube and this creates a stress raiser. It is very close to certain that a stress crack would start at this point leading to fatigue failure. Even without a gusset just the heat affected zone around the repair causes an abrupt change in the properties of the metal and this alone can lead to stress cracking and fatigue failure.

Long before I knew about stress cracks and fatigue failure I welded a fractured frame on a buddies motorbike; it was between the lower frame strut and the steering head. The repair lasted six weeks, and then broke abruptly and the front forks fell off. My buddy slid straight ahead and into a big evergreen hedge at the side of the road, at around 40mph, got up and only had to spit out a few pine needles. Not everybody can be that lucky.

Verfur
03-28-2008, 02:36 PM
It looks to me like it needs to be "V" cleaned and tig welded. And leave the weld bead proud. Do find out the correct material type
I have to agree with mactec54 it realy never got welded to begain with.

If it makes you feel better take it to an aircraft shop.

The bad thing will be the paint/ powder coating

Just my to cents.

holbieone
03-28-2008, 02:58 PM
Hi everybody! Thanks for taking me in. I really need some professional help on this. I would really appreciate everyone opinion.

Take a look at these pictures and tell me what you think. They are informing me that it can be "temporarily" repaired and ridden with the temporary weld. I don't think so. In my opinion it should have never been welded like this in the first place, but I'm not expert on welding that's why I need all of you.
Please tell me what you think. I would really like to hear your imput on this.
Let me know if the pictures came through.
Thanks so much!
-jane

are they going to replace your frame ?

I've seen this before with those custom frames ,anyone out there can slap together a frame (with no welding skills) and call them self a bike builder

and the other sad thing is some are coming out of china ,kind of a kick in the $alls if you ask me

as far as the re welding goes ,if done correctly it should last but i would pull the frame apart and clean the insert and the inside of the tube then tig weld it back up

ThatguyDave
03-29-2008, 11:18 PM
I hadn't though about there having never been any weld there to start with. I was seeing the clean break, sans weld and assuming that the inner piece was something added after the bread to assist in rewelding the frame back together. If that inner tube was present prior to the break then it would make sense that it was put there to act as sort of an interal lug to help align the frame tubes together prior to welding. While I can imagine someone would be dumb enough to grind away a steel weld for cosmetic reasons, it doesn't look to me like this is the case here. Good thinking though. Maybe the situation isn't as destitute as I thought and a good weld will suffice.

Dirttrackers cut the chainstays to increase traction? I'm dying to see a dirt track race but I haven't been able to find a track near NYC or Springfield OH where I constantly flying to for business.

offroadxx
03-30-2008, 10:49 PM
It looks to me like it was a soft tail style frame and someone went to put an aftermarket hardtail kit on it and forgot to weld it before they powdercoated it. You can now buy the hard tail kits with the rear back half and slugs to go inside of the frames which are usually 1 1/4" DOM .120 and they send you a 1" set of slugs for the inside so you have something to weld the backhalf to. TIG weld the thing like it supposed to be, re powdercoat the the thing and call it a day. They do it all the time for hardtail conversions.

greg b
05-06-2008, 09:06 AM
Hi janefox dont stress to much about that frame as some other members have stated it looks very much like it was never welded.I do this kind of work for a job (motorcycle engineering) on all makes and models, it appears theres a spigot inside the tube and if there is it needs a slight root gap placed between the two main tubes so when the welding is done it will fuse the spiggot to the main tubes.For extra strength they can shallow spot drill either side of the tubes and plug weld the spigot to them,get a guy who knows how to weld & prepare properly and there should be no probs.I use tripple deoxadies tig and mig wire for most welding applications on frames.Make sure the repairer knows what he or she is doing and there should be no probs.regards greg.

mc-motorsports
05-06-2008, 10:21 PM
That frame is aftermarket, correct? Custom built? Looks like they used a sleeve inside to line it up for welding and the builder didn't know what he was doing.

First thing I would do is take it back to the manufacture/builder and tell them to write a check to a competent welder to fix thier crap.

They just find a good certified TIG welder and it's no problem!

holbieone
05-07-2008, 08:28 PM
janefox
join date 03-27-2008
Last Activity: 03-27-2008 10:54 PM

1 post

i don't think this person is coming back to read this post


janefox

if you ever come back please let us know what the out come was