A ton of questions. 70 CT70

ChopperG

Member
Gold Candy original paint. Will paint stripper create any problem's on the frame, tree and swing arms?
I've used a lot of stripper on cars in the past. Post cleaning the parts prior to painting is the key. Any problem on these bikes as opposed to bead blasting or sanding?

Are or can the stickers on the bikes be covered with clear coating during painting?
Thanks, ChopperG
 

69ST

Well-Known Member
Chemical stripping/cleaning is okay, with a few provisos. All surfaces must be completely clean and chemically stable, before the first application of primer, to prevent lifting/blistering. The seams are the biggest concern; they're all but inaccessible and will hold chemical residue, as well as rust. That pretty much rules-out most immersion processes. Methylene chloride is the most effective stripper, it also causes rust; keep it out of any & all seams or you'll have a nightmare. It's a highly noxious chemical and known carcinogen.

Best application for paint stripper is the outside of the frame. It'll speed paint removal. It should also be followed by low-pressure bead blasting; that's about the only practical means of cleaning all of the various recesses. Other than the frame, itself, the rest of the tins are small enough that it's just quicker & more efficient to bead blast them. You also don't want stripping chemicals getting inside a K0 upper fork unit, or swingarm...which has lots of internal pockets. The rubber pivot bushings don't like solvents.

Figure roughly 20lbs of glass bead, with a decent blast cabinet & compressor and the better part of a day to get everything back to clean, "white" metal. The lion's share of that workday will be spent getting all the little details of the main frame, especially in the wheel arch...both inside & out.

Normally, you'll want to apply epoxy primer-sealer ASAP. Then any polymer fillers. If you're lucky enough to get a few days of low humidity, the scratch filler can be applied direct-to-metal - before the primer-sealer; that's ideal for adhesion, just not always practical.
 

ChopperG

Member
Yes, thank you Sir for the information. You pretty much convinced me to go with the bead blasting. As you pointed out. There's a lot of seams for the paint stripper gel to get into and be a pain to get out.
The tack pins on the vin plate. What's a good way to pull those out with out tearing up my plate? Is there a replacement pin / tack for the plates? I don't want to scratch or bend the plate.
Thanks again for this info.
ChopperG
 

cjpayne

Well-Known Member
I think harbor freight makes the tool or maybe DrAtv. If you take some fishing line and start at the corner, you can get it to peel the tag without damaging it.
 

ChopperG

Member
CJ payne
So do the tacks pop right out pretty easy? is there a replacement on the market? I think I saw a set of what looked like tacks for the plate on the CHP site. Not sure though.
BTW I just book marked your step by step write up on the clutch and oil filter clean out. Great job.
Thanks, ChopperG
 

cjpayne

Well-Known Member
Not really. Most people use a punch, then drill out. Be careful as you might widen the hole. I think you can still get those OEM, but don't know if the CHP or DrAtv ones are OEM correct.

Be sure and post if you use the spinner/filter thread. Feedback always welcome.
 

ChopperG

Member
Oh Yea. No doubt I will credit you and your spinner/filter thread with all the credit it deserves. Here's the way I see it. After reading and studying your tutorial on how to check this item gave me a set of balls to jump in and do it.
Much appreciated.
I managed to get the data plate off the bike this morning. However the brads/tack were pounded in so hard that there was no way to get in underneath one of them and pull or pry it out, so the plate did pull off over the head of the tack but doesn't look to have damaged the plate to much. Looks like I can reinstall it after the paint job.
Like in another thread I read, I thought I'd be able to push them out from the inside out so I found out that is not going to happen due to the double wall steering neck keep that idea from happening. Ha
Thanks again, ChopperG
 

ChopperG

Member
So while I'm right there working on the steering neck on the bike. The next question is can I pop out or knock out the steering ball bearing race (top and bottom) with a some sort of tool? I have a variety of punches and chisels I can use.
The bearing race looks pretty good. Not sure if I really need to remove the races but will for sure replace the ball bearings. Just want to lean how to remove the races in case I need to on the other bike.
Thanks again. ChopperG :scooter:
 

kirrbby

Well-Known Member
You can just tap them out, working from the opposite end with a punch etc. Work all around the perimeter, slowly driving them STRAIGHT out.
 

ChopperG

Member
Thank you Mr. Kirrbby,
Thought so but I like to confirm things before I start to tear things up. LOL
So is it safe to say I can or could install the bearing races with a bearing press and or a correct sized socket and press it into place? I don't want to push them in to too far. Is that correct?
Thanks.
 

69ST

Well-Known Member
Seems a bit ironic, the most violent and delicate R&R projects are side-by-side, literally, on the steering head tube.

Removing the original drive screws, without damaging the VIN tag, takes sound judgment and a surgeon's touch. Being able to remove them, intact, such that they can be reinstalled is rare. They're usually oxidized in place and the original friction-fit was, by design, extremely snug. 95+% of the time, it's best to just centerpunch then drill the heads. And that's not easy to execute well...but...it can be done.

As for the steering head outer bearing races, those don't necessarily have to be removed. They can be masked. If you're going to remove them, best to do so after the paint is applied; that way the seats will be clean, bare, steel. The interference fit is so tight that a minuscule coating (like overspray) will create a nightmare, come reassembly time. A feeler gauge, or fingernail, can be used to verify that these have been fully seated. That is, if you lack experience, or a dental mirror.

Refinishing one of these framesets, doing it right, is a painstaking process. Like anything else, it's all in the details. Unlike the autobody equivalent though, it's mostly details and what might be passable on a body panel will look horrible on a bike. With K0s, especially, look closely for small stress cracks along the outside edges of the triangle, above the upper motor mounts; if found, they should be welded. Most of these framesets will have some rust pitting and at least a few small dents, most of which won't be visible until they have been primed & blocksanded...then viewed in optimal lighting; that's what'll bite your arse, if overlooked. There's nothing like a fresh application of candy color paint to magnify surface imperfections. The factory didn't always get them 100% right either. Don't be surprised to discover a few paint runs and some leftover welding slag, as you carefully blast down to clean, white, metal. The question becomes what are you willing to live with? Translation - lots of skilled labor and patience and the latter can go a long way toward overcoming a lack of the former.
 

Adam-NLV

Well-Known Member
So while I'm right there working on the steering neck on the bike. The next question is can I pop out or knock out the steering ball bearing race (top and bottom) with a some sort of tool? I have a variety of punches and chisels I can use.
.
Thanks again. ChopperG :scooter:
I use a piece of Rebar to reach the races and then a hammer to tap them out. Replace them with ALL Balls bearing set, it's a lot better than the stock loose bearing set-up.

Freeze the bearing for easier installation, there's a thread on doing that installation somewhere on this site....:4:
 

bc17a

Well-Known Member
Yes, thank you Sir for the information. You pretty much convinced me to go with the bead blasting. As you pointed out. There's a lot of seams for the paint stripper gel to get into and be a pain to get out.
The tack pins on the vin plate. What's a good way to pull those out with out tearing up my plate? Is there a replacement pin / tack for the plates? I don't want to scratch or bend the plate.
Thanks again for this info.
ChopperG


I first use stripper to get the bulk of the paint off before blasting. This helps the media last longer and cuts the blast time to about half or less.
 

ChopperG

Member
Here's a few pictures of the plate after removal and the tack/nail as it may be called and the bike with the plate still on the bike for a reference. I think I got lucky with the removal.
BTW, I used a razor blade to get under the plate and the one tack.
Stand by for the pictures.
 

ChopperG

Member
Had trouble uploading pictures from the other computer.
DSCF2885.jpgDSCF2945.jpgDSCF2952.jpgDSCF2930.jpg
 
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