Triple frame cracking?

1200ts

1200ts

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USA - Riverside CA
As I have the front forks off my 3CL to rebuild and will be putting on four piston calipers, I thought it may be a good time to strengthen the front down tubes before they crack.

I was talking to Wolfgang this morning and he said only 120 frames crack. He has never seen a cracked frame on a 180 and there is no need to do anything to it.

I thought both frames have the same problem?
 
There are also fotos i. e. from Red of 180 frames with cracks and where the front was totally removed from the rest of the frame.
 
My 79 Jota frame was cracked when I rebuilt it a few years ago and I know of others in AU. Granted, mine was a high mileage bike used on bad roads with a few crashes thrown in for good measure (including a biggie).
If yours hasn't cracked yet it does beg the question, is it going to be used hard enough for long enough to crack in the future? From that perspective, Wolfgang is possibly right and the answer is probably not. It's easy enough to do in the future if indeed it does crack, and the cracks can be there a LONG time before anything drastic happens.
 
Only Laverda frame that seems immune to cracking is the 500/600.

Triples crack at the front down tubes, 750s at the rear engine mounts. Triples have a structural weakness, the 750 issues are mostly owner induced.

To be fair, it's mostly hard-ridden bikes that suffer. Brake and fork upgrades and using them as they are meant to are surefire causes for future frame failures.

piet
 
1200ts said:
As I have the front forks off my 3CL to rebuild and will be putting on four piston calipers, I thought it may be a good time to strengthen the front down tubes before they crack.

I was talking to Wolfgang this morning and he said only 120 frames crack. He has never seen a cracked frame on a 180 and there is no need to do anything to it.

I thought both frames have the same problem?
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“Only 120 frames crack” …….. well look at this bad boy 180 frame before my repair last year ! I’ve seen several being ridden and I know some of the owners are aware !
 

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I have said this before and will say it again. 180 frames do defniately crack at the headstock, I have repaired about five over the last forty years and three 120/RGS types as well. My own bike (TOG) is fitted with 320mmm discs and 4 pot callipers plus 916 master cylinder, the frame has never cracked. The frames that I have repaired have all shown signs of "incorrect operator technique" on behalf of the individual welder who atatched the tubework together. The frames were contracted out to Verlichi and they may have had several welders if not a few dozen, the welding defects that could be seen by x-ray inspection or under the welding process (but not by naked eye) were mainly "hot pass" i.e. very high welding current and moving too quickly, affecting the parent metal close to the weld called "HAZ" (heat affected zone). This allows the carbon in the steel (not much of that anyway as its more like gas barrel) to escape, and the tube lozing strength, before clean up and painting this can be identified as a black ring around the tube either side of the weld.

And dont even get me started on RGS fuel tanks which are welded by the carbon roller method on mating flanges of the top and bottom sections (hence the ladder rail marks on those flanges) and where the corners are too tight, transitioned to TIG edge welding, for maybe 40 or 50mm resulting in two very week points per corner, where the edge weld joins the flange weld, strip completely the paint from one and examine it with an eye glass before making a return comment.
CLEM
 
Its not often I agree with Clem but this is an exception. :) Many years ago, both down tubes cracked on my 3C and in France! I managed to limp home and one of my mates took the frame into Heathrow where a BA (CAA certified) welder, welded the down tubes and very neatly added some discreet aircraft quality steel gusseting around the headstock. This resulted is a far stiffer headstock and a better handling bike. Still good today. :D
 
3crider said:
Its not often I agree with Clem but this is an exception. :) Many years ago, both down tubes cracked on my 3C and in France! I managed to limp home and one of my mates took the frame into Heathrow where a BA (CAA certified) welder, welded the down tubes and very neatly added some discreet aircraft quality steel gusseting around the headstock. This resulted is a far stiffer headstock and a better handling bike. Still good today. :D
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Can't beat doing a nice little homer at work (y):cool:
 
Hey, hey even I have found dreaded (suspicious) cracks in my 3CL frame. Not sure if I should stop riding immediately or just continue with my old fart style of riding and keep an eye on their development until the off season. Also how do you people weld/fix them? The cracks are visible in the paint and very faintly visible under the paint and not complete. I attached some pictures:

Br
Axel
 

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just put Gaffer tape on the cracks…..:ROFLMAO:

as I see in your fotos both tubes have cracks and one crack is almost around the tube. It has to be repared immediataly, I would not ride the bike any more.
Red has posted a foto where the front of the frame was totally seperated, do you want to ride such a bike and risk your life??
You may just weld the cracks and controll continously or better add some plates to stiffen the frame.

Good luck
Andre
 
Nah... might shake its head a bit more than normal, but certainly won't seperate suddenly. There's still the triangulation holding it together a bit. ;) But it's not going to get any better, so you may as well tackle it immediately and consider some additional gusseting while you're at it. Bit of a shame it's cropped up in the middle of your quite short riding season...

When I found my own frame cracked the first time, I panicked. But I really didn't know for how long it had been cracked and hadn't noticed anything out of the ordinary!

piet
 
Lots of info on Gussets for the RGS in the forum. Hopefully a search will turn up similar for your 3C.

I did my RGS as a precaution when I was getting the frame powder coated so the work to strip the bike was already done. Not as much fun to prepare it only for the repair. I'm a chicken shit welder at best so I made the gussets but had a real welder install them.
 
Thanks, wasn’t aware of the right wording for a search. ”Gussett” gave lots of ideas and also insight in the fact that winter season may have arrived already this year… unless I use the Norton method. Or go the Gorilla tape way. ;)
 
adding gussets is a good idea but it is frought with problems relating the the ignition coils and electronic hardware (mainly on 180's) so a bit of thinking or relocation of components needs to be thought of, nice sweeping down to nothing gussets is my prefered method, the nuisance hardware comes in second, stiffen the frame first, sort the electrics second. Still never had to do it to TOG.
CLEM
 
chrisk said:
May be elegant, but a bit of TIG will see you do it again and again until you brace it too.
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Reckon you're right Chris.

That does aid the tube bits holding together, but the forces that rip them apart are in no way addressed.

piet
 
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