Frame

Mr Nairn told me that is how you check for a bent frame......sorry.
 
Wannabe Ferrari owners pay a premium for short wheelbase models, you got it for free! :D

Reckon it gets around corners really good, just a pity the front mudguard stay will clout the centre exhaust header...

Not normal, but very common, unfortunately!  Got one of those in the workshop at the moment, owner hasn't yet decided on course of action.

OCT in Germany has NOS frames for almost every model triple if you decide you need one.

piet
 
Looks just like my frame before I sent to Dave Kellett. He got it straight.......just like his ad says.

If you choose this path also get some extra bracing added under the steering head. According to the frame guy my whole rear sub frame was corkscrewed as well. Probably from a previous owner chucking wheelies. He reckoned the Laverda triple frame was way too easy to bend.
 
1. Find out the area of the bend
2. heat the opposite side of the tube in about 20mm sections to dull cherry red and quench with cold water,
So about 10 small hot spot and quench repetitions on a 200mm bend. (think of the heated area as a tiny wedge of cheese with the thick part away from the bend and the thin part just going past 2/3 thickness of tube)
3. watch the frame rail slowly straighten
4. Repeat where needed.
5. Be patient, do it gradually, it will work!

Julian
 
Hi
Thanks for all the "good" response
As I see it,it is difficult to understand the power that can bend a tube of that dimitionen, without taking anything with it in the "fall"
  If you have a tringel and bend one side, so affected the other two sides also.
But my  two downward pipes are straight, bearing holes are round! and i cant se anything else bent.
( It is a 120 , 82 jota )
My plan is to go for heavy duty 6 pistongs ,320mm brakes. but if this will be the result iam a little concern.
Johan
 
I should think that frame is ex-factory. That's why some high class race preparations included sawing the top tube and welding back after having inserted a steel tube inside.
Paul
 
Johan,
Big brakes don't have that effect on a Laverda frame, they are not the best frames around but they are not that bad.
That looks like it has had a front end shunt at some stage, I have 3 frames here with similar bends in the same spot, one a lot worse then your frame, other two not so bad.

you could press a lot of that out by setting up a strong back arrangement, would not get all of it but metal does have memory and will easily head back to where it was
you would need to make a press plate that matches the spine, as in a 1/2 piece of well fitting pipe with a flat pad welded on top
decent chain to attach to the headstock and to the cross brace, add a 10 ton hydraulic jack

carton of cold piss for when all goes wrong :D

finish the job off by doing what Julian suggested
 
johan said:
My plan is to go for heavy duty 6 pistongs ,320mm brakes. but if this will be the result iam a little concern.
Click to expand...

You'll need decent forks and yokes first, and a lot of strengthening around the headstock.

I'm quite certain that braking forces are not to blame for your frame "misalignment", nor have I noticed it on my frame.  I have been running 4-pot calipers on 310mm, now 320, discs for years in my 3C.  But the headstock is heavily gusseted and the forks are quite strong M1R.

When I upgraded my P08 brakes and front tyre using a stock Ceriani fork, this quickly surrendered.  Stanchions far too weak to withstand heavy braking for long, slider wear was awesome!  Fitted a Marzocchi, slider wear also quite awesome but the stanchions are quite a bit stronger due to the increased tube wall guage compared to the Ceriani, so a lot less flex.  Just about tore off the headstock though... both downtubes fractured just below the headstock.

With the bend in the middle of your top tube, the downtubes will show only very slight bending along their length, but it will be there!  The head-on frames I have seen all showed the top tube bending imediately behind the headstock tube and the the downtubes showed creasing imediately below the headstock.  This is also the area where the downtubes usually break.

piet
 
Good advice from Red and Piet,regards bracing I took such in the past,from Alan(A14RGS) my 120 frame is braced either side of the headstock,it has 320 discs,4 pot Brembos and a Tarzo fork brace I inherited.The 1200 has been braced at the front coursey of Reds pic  ,but will be running standard Brembo PO8s and cast discs.

LJ
 
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