Author Topic: Restoring a rusty frame?  (Read 1979 times)

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Offline Graeme M

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Restoring a rusty frame?
« on: October 26, 2008, 09:43:19 pm »
Stripped my YZ250G project today and discovered that it has plenty of rust. Looks like someone has ridden it in salty/sandy conditions (a beach?) and then parked the thing without washing it. There's surface rust which isn't too bad, but looking up into the main tubes themselves shows me a lot of sand and crap. As near as I can tell the rust inside is not too bad either, tho noticeable. Overall I think the frame is OK. My question is - is there a treatment/process for cleaning out inside the frame tubes and stabilising the rust before I get the thing blasted and powdercoated?

Offline rocketfrog

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Re: Restoring a rusty frame?
« Reply #1 on: October 27, 2008, 07:46:06 am »
Graeme,
           the area which you should pay close attention to with this one is the downtube gusset. I have two of these models and the H as well, quite a few I have seen have either been repaired or are suffering similar deterioration in the same area. If you strip the paint you should be able to detect gross cracking across the gusset if it is present, however I have performed  radiography which discloses the internal damage, if you have concerns, unpick the gusset and examine the frame downtube for rust. Magnetic testing methods serve well to show up cracking to 0.080 inches or 2mm in the gusset only if you go that way. Total catastophic failure is immenant if the machine is used for its intended purpose carrying this type of underlying damage, I was lucky to detect the early signs while washing up after a big practice session. The gusset was torn through, and the down tube starting to bend as a result- and that was on a machine that actually looked good on the face of things! So if it looks corroded, my advice is to thoroughly examine the frame, check out the L/H rear sub frame area for weakening where chain rash occurs as well ;)   
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Offline rocketfrog

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Re: Restoring a rusty frame?
« Reply #2 on: October 27, 2008, 08:36:47 am »
Graeme, check out "Frame Rot" by Facthunt in this forum, you will see a photo of the area i'm talking about. "Deoxidine" is the product you would use to restore lightly rusted surfaces.
Political correctness is a doctrine,fostered by journalists and politicians, which holds forth the proposition that it is entirely possible to pick up a turd by the clean end."

Offline Graeme M

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Re: Restoring a rusty frame?
« Reply #3 on: October 27, 2008, 01:35:09 pm »
Thanks for that. And yep, that is definitely a problem area on mine too. Looks like the frame will need some careful checking out and fixing. Still, it's waaay better than the insides of the motor...

Where can you find deoxidine? Just the usual places, or do you need to 'come out the back'?

Offline rocketfrog

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Re: Restoring a rusty frame?
« Reply #4 on: October 27, 2008, 03:43:07 pm »
Deoxidine is available from automotive spray painting and panel beating supply stores no worries, a little goes a long way so 500ml should be fine, although i think the smallest container is 1litre, could be wrong though. I am actually considering tooling up for a remanufactured gusset, since I need to do at least 2 and there are plenty more who would benefit from a replacement. check out how this problem has been remedied on subsequent frame design, they have actually left a small gap to permit trapped soils and moisture to escape. YZ/IT 250 & 465 g/h all suffer the same design flaw.
Political correctness is a doctrine,fostered by journalists and politicians, which holds forth the proposition that it is entirely possible to pick up a turd by the clean end."

Offline caps 999

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Re: Restoring a rusty frame?
« Reply #5 on: October 27, 2008, 05:03:33 pm »
dont forgrt the yz250j i think that was the king in this department :'(
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Offline maicomc490t

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Re: Restoring a rusty frame?
« Reply #6 on: October 27, 2008, 11:10:55 pm »
You could always ditch the Yammy and get a Maico, lol !!!
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Offline caps 999

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Re: Restoring a rusty frame?
« Reply #7 on: October 28, 2008, 09:53:19 am »
what you mean a glorified rust bucke lol  :D
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