OzVMX Forum

Clubroom => Tech Talk => Topic started by: CRTAD313 on September 15, 2012, 01:00:46 pm

Title: Frame fix?
Post by: CRTAD313 on September 15, 2012, 01:00:46 pm

I have bought myself another 1984 Cr500 as a parts bike , after getting it home i was starting to think it really doesn't need that much money to live again just time.
But after going over the frame i discovered the frame is pretty average on the bottom rails.
It has a few dents and a few small  rust pin holes in a couple of areas and definatly has the early stages of cancer.
My question is can these small sections of tube be cut out and new pieces welded in or will the heat distort the frame?
Or is the frame simply stuffed?

Title: Re: Frame fix?
Post by: Nathan S on September 15, 2012, 02:10:26 pm

Definitely sounds fixable. Worst case is to cut out the bad tubes one at a time, and replace with newly fabricated bits.

Title: Re: Frame fix?
Post by: oldfart on September 15, 2012, 03:07:32 pm

Something like this  ??? 
(http://i72.photobucket.com/albums/i180/mutchoo/Rm250bRhsrailrepair001.jpg)

Title: Re: Frame fix?
Post by: Lozza on September 15, 2012, 03:52:37 pm

Quote from: oldfart on September 15, 2012, 03:07:32 pm

Something like this  ??? 
(http://i72.photobucket.com/albums/i180/mutchoo/Rm250bRhsrailrepair001.jpg)

Found a use for all those GI pipe off cuts in the back of the ute Stew?

Title: Re: Frame fix?
Post by: bazza on September 15, 2012, 04:19:19 pm

 Stu how was ski in Unzud?
Warmer ski in unzud than VMX in Lithgow!!!

Title: Re: Frame fix?
Post by: oldfart on September 15, 2012, 06:53:47 pm

First up I will reply to 313 post  .....The section I replaced was badly dented and had a few pin holes, in my opinion it  was easier to do this than shag around filling rust holes and pulling out dents.
A hole was drilled in the frame to allow heat and hot air  to escape while welding.

Lozza .... GI pipes are history. It's PVc or HDPE  ;)

Bazza ..... Lithgow looked like brass monkey country to me  ;D  and Yes The Girls enjoyed the Snow. 

Title: Re: Frame fix?
Post by: Lozza on September 15, 2012, 08:45:05 pm

Quote from: oldfart on September 15, 2012, 06:53:47 pm

Lozza .... GI pipes are history. It's PVc or HDPE  ;)

Bazza ..... Lithgow looked like brass monkey country to me  ;D  and Yes The Girls enjoyed the Snow. 

What no GI?   No wonder the world is in such a state  ;D


Been the best snow in 20yrs here over 2m base, got to ski on dry powder for the first time.

Title: Re: Frame fix?
Post by: CRTAD313 on September 16, 2012, 06:49:11 pm

yep oldfart pretty much just like that, i thought maybe the welding might distort the frame but apparently the old girl will live again. Thanks guys

Title: Re: Frame fix?
Post by: oldfart on September 16, 2012, 07:02:39 pm

313.... best to try and tig weld it if you can, then a soft flame over the welded area to relieve any stresss.
Try not to be too savage with the grinder cleaning up your welds as it will only make the frame walls thin.

Title: Re: Frame fix?
Post by: Montynut on September 16, 2012, 08:51:04 pm

Oldfart a bit off topic. I have a classic road bike (Suzuki Katana 1100) with some frame damage (a common area of internal corrosion for those bikes)  that requires the same type of repair. I'm in NSW where could I get that type of work done. It is beyond my ability by a mile so need someone competent to do it? Any suggestions?