Cracked Fork Leg

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Rick F
Mach 3
Posts: 91
Joined: Mon Aug 07, 2006 6:35 pm
Location: Murwillumbah NSW AUstralia

Cracked Fork Leg

Post by Rick F »

Disaster!

after only a couple of thousand k's, (and I am still getting around to photos Steve!) I now have a crack in the base of the fork leg (RHS) where the axle passes thru and gets clamped by the pinch bolts.

These aussie country roads have taken their toll!

It is obvious I have tightened the pinch bolts too much (nice new stainless ones) the crack is in line with the axle and right across the fork leg right in the centre line of the axle, where the axle passes thru the fork. (did you get that!)

Can I just grind the crack out and have it welded? anyone?

If I have to replace the leg, do I have to do both?

they are ceriani forks on a 1978 750 GT

Thanks folks

Rick

MartinMille BANNED
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Post by MartinMille BANNED »

Dont stuff around with safety !!!
go and get a new one, dont repair brakes or steering golden rule
check this out at the UK site way better than a visit to hospital

http://cgi.ebay.co.uk/Laverda-Ducati-be ... dZViewItem

Rick F
Mach 3
Posts: 91
Joined: Mon Aug 07, 2006 6:35 pm
Location: Murwillumbah NSW AUstralia

cracked leg

Post by Rick F »

yeh thanks Martin,

I sort of feel the same way, but! :roll: I know that some of these alloy guys are artisans and can repair some of this sort of stuff better than new!

I do a bit of sailing (Sydney Hobarts etc) and have seen alloy masts & booms welded and repaired, AND this is the big deal, the insurance companies still insure the boats for the race!

so I was sort of thinking, as it is not structural per sae, it is just clamping the axle, not actually supporting it............maybe......

And there will be trouble with the treasurer.....I will have to get another bill past....all the previously approved funding, we all know where that has gone

Rick

Rick F
Mach 3
Posts: 91
Joined: Mon Aug 07, 2006 6:35 pm
Location: Murwillumbah NSW AUstralia

crackers

Post by Rick F »

So where do I go from here. :?:

I still have the crack in the fork leg. I have ridden the bike several times lately....albeit very carefully.....the crack does not seem to be getting worse. But thats what happens with cracks isn't it....sudden failure.

I am still toying with the idea of repair. New fork legs wont come quickly with the current state of our budget. (3 kids at school)

If I go for new legs, is it an upgrade to opt for marzocchi forks. I managed to obtain new ceriani fork tubes when I was reassembling the bike ready for the road. (the guy had hundreds of them! pm me if anyone is looking for ceriani fork tubes) I had some minor corrosion on the existing units...right where the tube passes thru the seal...so the forks would have started to leak in no time.

The ceriani seem to work well for my style of riding these days. I would like to keep the bike as original as possible.

I also like the idea of the in line axle, from an engineering point of view. leading axles look like you introduce an unnecessary turning moment.

Why are the marzocchi considered a better suspension unit? Does it really matter on an older style of bike....I am not classic racing....I have seen the progressive rate springs advertised....should I invest in a set?

I am probably looking for bang for my buck here...ie a noticable difference for money spent. I am not in a position to throw silly money at the bike just to say well its got this and that......

any way, it is raining heavily here and has been for several days, starting to get mindlessly bored....kids climbing the walls & no new posts to view on the forum....happy new year to all

Rick

Den
Mach 3
Posts: 89
Joined: Fri Apr 09, 2004 6:02 pm
Location: Florida, USA

Post by Den »

.A picture would help.
.

Rick F
Mach 3
Posts: 91
Joined: Mon Aug 07, 2006 6:35 pm
Location: Murwillumbah NSW AUstralia

Cracked fork leg

Post by Rick F »

try these photos.

may work may not

thanks

Rick

The bike is a bit dirty at the mo :oops: work in progress!

Image


Image

Vince
750 Sport [BEVEL]
Posts: 207
Joined: Tue Nov 09, 2004 12:28 am

Post by Vince »

One of the local Laverda blokes was on his way to the Chrismass Party last year,riding 2 up and crousing past the RAAF base at Richmond out of Sydney when out of the blue one fork upper snaped in half,we found it had cracked at sometine in the past below the oil seals,he has fork leak problems for a while,quite a bit of damage to the bike but both riders were ok,maybe the weld would be ok,especaly if its xrayed but if I was riding it the naging doubt would wee wee me off a lot.

MartinMille BANNED
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Post by MartinMille BANNED »

Rick
As bad as your money situation might be at the moment, I would still replace it the leg for piece of mind like Vince said a lot more damage will be done if it gives way
I also think that the repair would come close to a new set legs

Being a mechanic we have a saying don't F... with Brakes and Steering just the thought of a crash would turn me off riding it.

Rick F
Mach 3
Posts: 91
Joined: Mon Aug 07, 2006 6:35 pm
Location: Murwillumbah NSW AUstralia

cracked leg

Post by Rick F »

Thanks Martin & Vince,

I know I know.

It is so hard to just let it sit there while I save up

You are probably right about the xray/repair, probably, by the time I pull it apart & run around.......be close to the same money

Do you think it necessary to do both?

David Frith
Cucciolo - the Lil Pup
Posts: 11
Joined: Sun Apr 22, 2007 7:36 pm
Location: Belmont, NSW, Austalia

Post by David Frith »

Hi,

Had a look at your photos, its a little had to see the crack. Is that it on the centre line of the axle?
It would be much safer to grind and remove the crack and have it TIG welded up than ride around with the crack unrepaied.
After grinding to remove crack it needs to be dye penetrant inspected to see if the crack has been fully removed.
After the welding is competed you would again need to dye penetrant inspect to make sure no other cracking has occured around the heat affected zone.
I would have no hesitation in using you forks after this work was carried out by a reptable trades person.

Regards
Dave
Dave F

Rick F
Mach 3
Posts: 91
Joined: Mon Aug 07, 2006 6:35 pm
Location: Murwillumbah NSW AUstralia

Cracked fork leg

Post by Rick F »

thanks dave,

you are the 1st person to offer such an opinion and sound like a professional, or at least with some experience.

Yes it is the crack thru the centreline of the axle.

I have sort of had the inkling that a good tradesman should be able to do it. as I have said previously, I have seen stainless & alloy repairs on some of the big Hobart yachts, in very high load areas, and their insurance still covers them.

any idea who might be able to do it... :lol: ...happy to send it somewhere on the east coast

Thanks
Rick

MartinMille BANNED
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Post by MartinMille BANNED »

Rick
Why dont you phone Desmo... at Byron bay or closer to you at nth coast C/harbour Ducati and ask them where they send there stuff to

better still give Ron Young a call 02 49 388 097 and ask him as he does everything including this type of repair , he is doing my engine at the moment nothing mayor just 5th gear LOL..and beading etc etc etc
He does have a bit on at the moment but his work is A1

good luck mate

Vince
750 Sport [BEVEL]
Posts: 207
Joined: Tue Nov 09, 2004 12:28 am

Post by Vince »

Pete Smith of Epicycle is up that way somewere as well,very cluey engineer,what is it with all the old stagers moving up there.

Rick F
Mach 3
Posts: 91
Joined: Mon Aug 07, 2006 6:35 pm
Location: Murwillumbah NSW AUstralia

cracked leg

Post by Rick F »

Thanks Very Much Folks,

I suddenly have a price from R & R at Tumbi for $175 for a new leg.........add seals..........& mounting studs.......plus about 8-12 hours of my labour which I would have had to do anyway.

so I will probably keep my existing leg & get it repaired to keep as a spare.

I may order the other side in the near future to have just in case!

sounded like a good deal & affordable. The kids may have to miss out on pizza....ballet lessons.......use last years school shoes.......& I pay the fees a bit late.

My wife made a comment that my priorities seemed to be a bit askew! can you believe that!

Thanks again

Rick

Vince
750 Sport [BEVEL]
Posts: 207
Joined: Tue Nov 09, 2004 12:28 am

Post by Vince »

Gees whats wrong with her,its a bevel isnt it.

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