1982 CB750F...Better Devil

Yeah, I was afraid you may say that! There are a few spots where the paint job is pretty rough so I may attack those with stripper, but thankfully they're in fairly easily reached areas. The thought of stripping off all the paint though, that sounds like a nightmare. I'll get the worst off, and chalk the rest up to experience...
 
i had to deal with a spray bomb once. Get some expanding rubber plugs in the intake and exhaust ports, refit all your engine cases and go nuts with the stripper. make sure you wear safety glasses when you are using it with a brush cuz it can flick it into your eyes. Ask me how i know....
 
I found that out the hard way already Doc. No running water in my garage (or near it)...covered in the stuff I had to make a mad dash outside and bury my arm in the snow up to my shoulder. Every time I think about it it reminds me of the scene in Raiders of the Lost Ark, when the nazi bugger picks up the red hot medallion and makes a beeline for a snowbank. My yelps were just as lame as his.
 
Not a million miles off painting this thing now. Found a rather sculptural position with a fairly solid balance point -

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- and wondering if that may be a good position to paint it? I'll probably pull the oil pan off first though and this will probably upset the balance. If anyone reading has painted one of these lumps before (assembled) and has any pointers re. positions for engine let me know? I'm thinking two positions - one to get the underside and then roly-poly it to get the rest.

Is primer the way to go? This engine has been painted before but without primer.

In other news, I'm going to have to modify the frame brace a little here -

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I'm using a K tank on this F frame and so the mounting position is different. It also doesn't sit flush with the seat frame rails on the horizontal, so in order for it to not get in the way of the seat pan it'll need to be lowered. However the battery cage also mounts to this so I'll need to be careful with the grinder. Plan is to cut some slits out and lower it, then re-weld. In my head it makes sense.
 
Clean it really good and prep it right and you dont need primer but you do need to heat cure either in an oven or by running the engine with duplicolor or vht engine paints. Oh and I should get over this week to get the carb kits and put them on the bus to you.
 
Legend, cheers Mike - carbs are next-ish on the list so that'll be good timing. No primer? Sounds good to me. The selection of VHT paints at Canadian Tire seems to have slimmed down a bit so may end up with a Duplicolor engine enamel instead. Looks like they're much of a muchness.

When you say prep it right - so far I've de-greased the bejeezus out of it, cleaned it up with S100 and a load of brake cleaner and keyed up the remaining paint/aluminium cases so the paint sticks good and proper. I still need to wipe the thing down with thinners - is that pretty much it?

Also, will have to cure the paint by running the engine once it's back in the bike - no oven here.
 
Yep pretty much that, getting as much oil residue off as possible makes the most difference. I like a wash in full strength simple green, then a good rinse with water as well. Plug the holes.
 
I've always scuffed with 320 grit or similar. And used primer. But since this already has paint on it you'll probably be ok without.
 
advCo said:
I've always scuffed with 320 grit or similar. And used primer. But since this already has paint on it you'll probably be ok without.

I follow the can, I know some don't need primer and some do depending on brand and possibly colour you use. That being said I always have baked my covers in the oven and then cured the cases with engine heat per cans. I just use a toaster oven in the garage for the covers. I got one cheap at a thift store that can fit a 12" pizza and so can take most engine covers.
 
Maritime said:
I follow the can, I know some don't need primer and some do depending on brand and possibly colour you use. That being said I always have baked my covers in the oven and then cured the cases with engine heat per cans. I just use a toaster oven in the garage for the covers. I got one cheap at a thift store that can fit a 12" pizza and so can take most engine covers.

True. When I did the 360 I cured all the pieces individually in a ghetto oven with a heat gun. On the 350, I painted it completely assembled on an engine stand, and didn't cure it until I had the bike running, which was a few months later. I believe I used Duplicolor on the 350, and it was gas and oil resistant even before I ran it in to cure the paint. I did the same on the RV125.
 
I'll check out what Canadian Tire has in terms of high heat paint and weigh up the options. Wasn't planning on using an engine stand as, well, I don't have one. But, thinking about it, my wife bought me a one day welding course for Christmas so maybe I could have a go at making one for my first project. Would have to make painting the engine a lot easier - presumably with the engine on the stand there's no need to rotate the engine in order to paint it? Hit the thing all in one go?

I'm not painting the covers, they'll get a different treatment. I do have a small toaster oven in the garage I picked up for $5 - used it for baking Rhonda's calipers. I'll cure the engine paint once the engine is running, but yeah I've heard that it's not much cop against oil and gas until it's cured. Duplicolor is better in that dept?
 
The Jimbonaut said:
I'll check out what Canadian Tire has in terms of high heat paint and weigh up the options. Wasn't planning on using an engine stand as, well, I don't have one. But, thinking about it, my wife bought me a one day welding course for Christmas so maybe I could have a go at making one for my first project. Would have to make painting the engine a lot easier - presumably with the engine on the stand there's no need to rotate the engine in order to paint it? Hit the thing all in one go?

I'm not painting the covers, they'll get a different treatment. I do have a small toaster oven in the garage I picked up for $5 - used it for baking Rhonda's calipers. I'll cure the engine paint once the engine is running, but yeah I've heard that it's not much cop against oil and gas until it's cured. Duplicolor is better in that dept?

Jim, I cant remember but I think I used Duplicolor on the XL and VHT on the Van Van. Neither had a problem holding up to gas or oil. They had off gassed at least 1 month prior to being exposed to any fluids.

I thought I had a pic of the stand I used for the XL. Basically I made some 2x4 bases with a vertical board on either side of the engine. Just ran a threaded rod right through. Kept it about 8-10" off the bench which was just enough to be able to spray the underside.
 
That's good to know Nick - as long as they gas off before coming into contact with oil/gas then the paint should be ok? I'm looking online for plans for an engine stand - may have a go at building one. Otherwise I'll probably end up painting the engine as it sits on my bench, with a bit of finagling hopefully I won't have to move to around too much. Damn thing weighs a ton.

If I was to make the frame out of wood, think 2x4's will be strong enough to hold this thing up?
 
Here is my stand. I think I paid $30 for it. Could be made for much cheaper, but I don't mind throwing $30 at my own laziness now and then.

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I saw that exact stand Irk on amazon just now. It's for the SOHC motor though, not sure it'll fit the DOHC and can't find an off-the-shelf version for it.

And damn that's one clean looking engine by the way.
 
The Jimbonaut said:
That's good to know Nick - as long as they gas off before coming into contact with oil/gas then the paint should be ok?

From my experience, I haven't run into any issues. I still think you should avoid getting any gas on the paint until its cured but sometimes floats stick ya know?

2x4 should be fine, just put a brace in between the uprights because they'll want to bend inward with the weight. So you'll basically have an H with a 2x or 1x base on front and back, with a threaded rod or steel rod to hang it. Space the pieces wide enough that you can get the engine in and out.

Alternatively you could hang it from the ceiling of your shop. Lol.
 
advCo said:
Alternatively you could hang it from the ceiling of your shop. Lol.

I would, but I'm worried the chains would interfere with the duct tape that's holding the ceiling together ;D
 
Cleaning engines...the enthusiasm is hard to maintain. Still, it's pretty much a wrap - an indeed that's exactly where it's at now - tucked under a bin bag until I decide what I'm going to do next. With the mercury plummeting in my garage I pulled out the grinder and chopped off the old seat mounting bracket -

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- once I've welded in a locknut or something for the tank mount bracket then I think I'm good. This worked well on Rhonda so I made the same bracket between the frame rails for the seat and fender mount -

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- and then called it day. Colder than a polar bear's toenail today, minus 20 or some shit. Brrr.
 
Yeah - up that way and beyond. Montreal...where you can’t feel your face for four months of the year, and spend the other eight slowly defrosting. Madness.


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