Frame/forks Refinishing

[TomG]

I'm starting on a restore of a '78 MC5 400.  I'm at the point to have the frame stripped and repainted.  Any suggestions on the best way to get the old paint off and what the best match is for the original KTM orange paint?  The previous owner also repainted the front forks.  Looks like he did it with a brush.  Any ideas on how to get that paint off as well?  I'm concerned that sandblasting will eat away to much material.

[Rocket]

I use a glass bead blaster that is very gentle on the metal, even aluminum and magnesium as long as you are careful. I use the one we have at work, I imagine there are shops around that would do this for you.
Rocket

 

[sachsmx]

Sandblasting should work fine on the frame and will cost a little less than glass bead. I get frames done in my area for about $35 each. Since the fork sliders are cast and have a rough texture, sandblasting will work for them as well. Just be sure to mask off the the seal bore and below with duct tape to keep from damaging those machined surfaces. I usually use about 50-60 psi when sandblasting aluminum.

 

[john durrill]

Tom , no mater which you use  ( sand or glass) make sure and clean  the fork legs , use soap and water and get them spotless.
 the dust from either sand or glass gets into every nook and cranny and is death on tubes and sliders.
John

 

[Bob]

I use ordinary paint stripper from the hardware store. I sandblast rusty steel. I treat all steel with Metal Prep ( phosphoric acid ) available at your local automotive paint store. I polish aluminum with very, very fine sandpaper or steel wool and Simichrome. You can get Simichrome polish at any bike shop.

[TomG]

Thanks much for the info.  I was wondering about the grit factor on the forks.  Guess I'll have to disassemble the swingarm from the frame too.  Based on what I've read on earlier posts I'm not looking forward to that.

[Kip Kern]

60/80 Grit Glass Bead at 80 PSI will cover anything you wish to restore.  Plastic media will do nicely on the Steel Tanks for paint/rust removal.  Get a copy of the "SkatBlast" catalog and your blasting media questions are all answered!

 

[TomG]

I guess I just thought I was ready to have the frame stripped.  I'm having trouble getting the bearing races out of the steering head and the triple clamps.  None of the races want to come out easily and before I started to use a hammer and drift I wanted to make sure this was normal.  I also see where these races are hard to source so I was wondering if one option is to leave them in and then try to clean them up after the frame is stripped and repainted? Any suggestions?

[Rocket]

If you are going to use the races again, either tape over the race or apply heavy grease to them.  I have used both methods and either one will work.
Rocket

 

[TomG]

That sounds like my best bet then.  I don't think there's any way I could get the ones in the steering stem out.  Is the stem supposed to detach from the lower triple clamp? Mine won't (easily) and there's no way to get under the part the bearing race is in to remove it.  Sorry for so many questions but I don't have a parts manual yet.  I've ordered one from Al but he's having to print some more up and I'm trying to get this to the painters before next week.  Thanks again.

[nonwing]

Try taking the frame to a bicycle shop.  They should have a tool to press out the bearing cups from the steering head.  I've done this several times and it worked like a charm.  Hope this helps!

 

[Jeff Reid]

What about the color? Years ago I used Chevy engine orange to re-paint my KTM frames and thought it worked pretty good. Is there a better match?

Jeff Reid, VP Ohlins USA, Husqvarna and Penton/KTM collector

[tlanders]

I still want to and will probably paint my '78 KTM frame Penton silver/grey and pretend that it is still a Penton. With the white tank it will be so handsome, like the one in our featured bikes photos!!!

 

[Mike Lenz]

The bearing race holder on the stem should tap off. Start on the back side and get it to move a little then use a chisel or something to wedge in there and work it up evenly, it should pop off. The closest paint I have found is also the chevy engine red, Its real close.

 

[TomG]

I finally got the frame and forks back from the sandblasters. I've found some Chevy engine red/orange spray paint at AutoZone. Is this what you're referring to or is it something I need to get at a specality auto paint store?