I finally pulled the trigger and bought some pipes for my GT750 project. Seller claims they're rusting but undented. Having done the flat black paint on my old RD400 pipes over and over and over again after rain, I'm wondering if there are any new coatings I can use.
Suggestions on removing the rust short of sandblasting?
Will powdercoat tolerate exhaust temperatures?
Is there something cheaper I could use that will actually work?
I've always used VHT hi-temp header paint on chambers and headers, and cured accordingly, the coating held up reasonably well and held it's color better than other rattle can hi-temp paint. Always sandblasted too whether rust or not to provide some bite for the paint.
Recently sandblasted and painted a set of SBC Thorley headers w/ the 2000 deg. ceramic hi-temp but not cured yet. Should fire this week tho.
Keep us updated on the GT750, that'd be good to see one again. I still have one engine w/ ported barrels, squish head, chambers and Lucas ignition (had 8 stock at one time). There's some great sound from those triples!
Once painted, could you do header wrap? Or will the paint deteriorate and still rust under the wrap?
fasted58 wrote:I've always used VHT hi-temp header paint on chambers and headers, and cured accordingly, the coating held up reasonably well and held it's color better than other rattle can hi-temp paint. Always sandblasted too whether rust or not to provide some bite for the paint.
Recently sandblasted and painted a set of SBC Thorley headers w/ the 2000 deg. ceramic hi-temp but not cured yet. Should fire this week tho.
Keep us updated on the GT750, that'd be good to see one again. I still have one engine w/ ported barrels, squish head, chambers and Lucas ignition (had 8 stock at one time). There's some great sound from those triples!
"cured" means what, exactly? Put in an oven of some kind?
In reply to stroker:
Smaller parts can be baked in an oven.
From VHT: 30 mins @ 250 deg./ 30 min cool, 30 mins @ 400/ 30 min cool, 30 min @ 600/ cool 30 mins.
Or on vehicle: 10 min @ idle/ 20 min cool, 20 min @ idle/ 20 min cool, run at operating conditions 30 mins let cool.
Curing makes coating chemical resistant and more durable.
If you're trying to avoid sandblasting, I would at least give spray on rust converter and then high temp paint a try. It's cheap and I can't think a way it could hurt anything.
A few side notes: 1) Remember any coating will change the TUNE of the pipes as gas temps will change. 2) Header wrap will drasticly change the tune and pipe will rot faster then you think. 3) "Jet hot" or "Swain Tech" is a good choise but $$ and only if there cleaned extreamly well or new. 4) Normaly i use VHT and spray both inside and out this helps keep the 1st few inches from flaking. (side note: on chrome pipes this will stop the blueing for a while)
Cleaning and painting 2 stroke pipes is a every winter maintenance thing. It's why you have the old barbque still. Hose the inside with Easy-Off oven cleaner and place pipe in bar-be untill smoke stops rinse in to 5 gallon pail and repeat untill it clean inside and out. Hit with scooth brite and warm then paint. Repack the tip when done.
boil or evaporate the rinse water and dispose of the chunks of oil properly
Dwarf, how on earth do you spray paint the INSIDE of the pipes?
I think that you can get VHT in a pint can. Plug one end, pour in, plug the other and shake. Dump out the rest.
You can also plug on end, fill with BBs or nuts and shake to get the rust out. I would just oil the inside.
Just keep spraying and rolling the pipe around is how I've done it. I tryied a diffrent nozzle and a straw but that didn't work to well.
I vote for jet hot coatings- I have that on my car header and it wears really nice. Eastwood probably has some do-it-yourself coatings that would work.
Jet hot has a nice black. But don't drop ice cream on it...it will leave a white stain that will never come off and Scotch Britte with just dull it.....BTDT 
I added an extension to one end of my blast cabinet so I could do the DG chambers for my RD400 Daytona.
If you don't have a blast cab, use a wire wheel in an angle grinder, or a 3M Scotchbrite stripping disc to get the pipes to bare steel all over.
If you do blast - carefully plug both ends - a 2 stroke can ingest stuff from inside the pipes, which will include blast media if you don't plug.
I've used VHT 1200 degree black for decades. Spray on many light coats. Typically I'll use at least 1/2 a can on a pair of chambers. Let dry for as long as possible. Summer heat helps. Too bad it's snowing...
Reinstall, start and ride 'til they're fully hot. That's how you "bake" them.
