Here we go! Restoring 576/748

[Wayne]

Got the side stand tab repairs done. We had to put on a new reinforcement plate and then weld the tab in place. When the tab is at the correct angle there is a huge gap on the inside that has to be filled. Every bike I looked at was the same. Not sure why Honda wouldn't have made a radiused tab so it fits the curve of the tube. Oh well, it's fixed, probably stronger than new. Thanks to all who helped with this one. My welder was hard pressed to make the weld look as bad as some others on the frame. He couldn't believe the gaps etc. in some. I told them they are "character" welds, don't make it too pretty!   I'll smooth the grinder marks on the frame before blasting and it should all be pretty transparent when painted. 

[markb]

I think that looks pretty good.  Are you planning on putting an engine in the frame and hanging an exhuast pipe on it to check out, or just run with it?

[Wayne]

I'm just going to run with it Mark. I knew the fore - aft position to be correct just needed that magic angle. Thanks! I put a stand on and it measured the same as yours when up and pretty well followed the frame lines. If it is out, I'm hoping it's marginal. So, while I wait to send the frame out for blasting and paint I have been working away on the motor.

A couple of the main brgs looked "iffy" to me. I don't like when they are shiny on the back side and in these cases the size information was worn off. Could indicate the brg. moving a bit. A couple of the faces are slightly galled, not badly but galled non the less. I didn't even bother to plastigauge them. For $144.00 Canuck Bucks she gets new mains.

I couldn't find the markings on my crank so I mic'd it. All of the main journals fell within 35.99 - 35.995 mm.

So that makes my journals what looks like the Japanese equals sign in the manual chart. ( = )

My case is marked  B A A B A

So starting at the timing side the table would give me this selection of main bearings:

Green - Yellow - Yellow - Green - Yellow

Easy once you get your head around it. Also, I learned that all bearings, regardless of color are marked "STD". That really threw me off as I'm used to undersized bearings be marked as such.

I popped the rod cap's off for a peek and they look as smooth and shiny as new. I'll just platigauge them and re-use if within spec.

I decided to go with all new tensioners as well as chains. Figured I have the money fire going now I might as well really get it stoked! 

[Wayne]

Waiting for some engine parts so I thought I would just start to clean up the aluminum and see how it looks:

Nothing special in the before shot. Grease is washed off ready for a coat of paint remover.


Paint remover did the job nicely revealing a pretty nice shifter cover! I did no scrubbing or sanding with any type of abrasive before this shot was taken. I just wanted to get an idea what was under the dirt and clear so I could decide how I am going to refinish my covers.


I found this a bit interesting. It was under clearcoat so I'm assuming it was made this way. There appears to be an area that I thought perhaps had been polished. I ruled that out though as the "parting seam" between the two unique areas isn't uniform. It looks more like to me that the molten aluminum wasn't completely melted/blended before the pour which caused inconsistencies it the cover. Anyone ever seen this before?


So it looks like my covers are in pretty decent shape. Now what to do. I think I would like to land somewhere between satin and a high polished finish. Clear coat sticking is a must as I don't want the aluminum to become a maintenance item. I read that the Eastwood Clearcoast sticks pretty well. I'll probably use that.

[Steve Swan]

These inconsistencies "seams" in surfaces of covers are common.  Makes obtaining a perfect polished finish nigh, if not, impossible.  Hence, supporting rationale to have the semi-polished cover have clear coat finish to hide these "seams."

[Wayne]

Got around to pulling the rear hub apart and was pleasantly surprised when I cleaned up the flange. There was a layer of grease that had been there for an eternity I'm sure. When cleaned up I found that the original clearcoat and factory finish was virtually intact! The is the only aluminum piece on the bike in this condition so I get to see what the factory finish looked like. It is polished higher than I expected. It is reflective, but not like a mirror. I think it's the clearcoat itself dulling it down. Here's a shot. I guess I could have cleaned it up better for the pic.  



In this pic I note a couple of things. First, they weren't too fussy about polishing the whole flange. The buffer just went around the flat surface, and knocked off some areas of the bolt bosses as it passed by. Secondly, you can tell the buffer was going around in a counterclockwise direction as the reinforcement ribs were hit and slightly polished on one side. I'll call it the back side.  You can see it to the right of the bolt boss in this image.

[markb]

The same is true of engine covers.  When I worked on my early diecast it still had (what was left of) the clearcoat and you could easily see areas on the bottom of the alternator cover and the middle of the valve cover where it looks like it was never even touched with a polishing brush.  I think they only worried about the visible areas and did them as quickly and cheaply as possible.  Hmmm, that would be a good way to tell if an engine was original.  There is no way to replicate that look.

[Riccardo]

Effectively the parts in aluminum were not polished like a mirror.

They had a polishing to half between the opaque finish and polishes.

Some times i'm carried to think that the covers already polishes from the stamps came outside and therefore polished in superficial way with medium brushes and then painted.

[Wayne]

Just grinding away at small stuff, waiting for clearcoat to arrive so I can test my polishing methods etc. so I thought I would look at what's ahead. When I looked at the combustion chambers a week or so ago I got a bit of a shock. I called the PO to see what happened and he said a Spark Plug broke off so he removed the engine and "split" the plug to get the pieces out. In doing so the threads in the head are badly damaged. They will hold a plug, and it was driven that way but I will be repairing that part for sure. I was a bit concerned about the damage in the chamber but on closer inspection it isn't too bad. I think when we rebuild the head I will just smooth and sharp edges to eliminate hot spots and blend them in. If anyone would like to chime in, feel free.

Of course if I could find a "prefect" replacement head with no cracked fins etc. that would be the way to go!    



With Spark Plug Installed:

[Wayne]

Need some advise here guys. Looking at my seat latch, it's in pretty good shape. Should I refinish it or just get the Yamiya unit? The only problem I foresee in refurbishing mine is the slight wear on the face of the slider, and how would my plater zinc the slider shaft? Can the ramp portion be removed? The rest looks straight forward....I think! You guys always throw a curve ball my way though! 

[gane]

Wayne, obviously your' no "neophite"  and am hesitant to add. but main bearings sizes were/are determined by both case & crank demensions. Having case markings put you 1 step ahead of most. as these were the first to "dis-appear" (generally before the "magic marker" colors on the bearings themselves). crank sizes (both rod & main) were usually etched on the inside of the crank flyweights at cam chain. read left to right, 5 digits main, 4 digits rod. with a chart in the shop man to derive size/color..comparing case to crank clearances. Striations due to passing "debris"thru bearing are generally of little consequence, but any apperance of "copper" should be addressed. some "300" main bearins are NLA, but have been superceded to 422 or 425  (I think) at any rate plasitiguage doesn't lie. unless easily discernable damage has been done, My concern would be the maintaining of oil pressure  which after failed oil pumps/blockage falls upon wiped plane bearings. watching w/intrest, G

[kp]

Need some advise here guys. Looking at my seat latch, it's in pretty good shape. Should I refinish it or just get the Yamiya unit? The only problem I foresee in refurbishing mine is the slight wear on the face of the slider, and how would my plater zinc the slider shaft? Can the ramp portion be removed? The rest looks straight forward....I think! You guys always throw a curve ball my way though! 

Wayne, Mate, that is the original part and I would use it. These were changed at some early point but I'm not sure of the VIN. Given you have a low VIN I would use it. These can be zinc plated with the hard plastic/rubber section intact as can the springs so just go for it. If you find any trouble send the part to me and I'll plate it in my home kit.
Trick here is to buff the steel shaft to expose clean steel and plate it after a good clean in mild detergent and rinse in clean water.
Ash is also into plating so he may offer some additional advice.
Dead f'en easy  KP

[Wayne]

Thanks KP. If my plater won't do it I'll follow up with you. I figured there was probably a good reason for retaining the original latch.

[Wayne]

Need more advice guys, on carbs. Looking at them I'm not sure what parts should come off for zinc. Mine are a bit aged so it's hard to tell. Obvious seems to be the choke arm, linkage and related fasteners. Anything else I should send out? I think I'm going to going with the zinc/nickel process as it is more robust than just zinc and looks identical. There is a minimum $175.00 charge so I want to get everything to them the first time! (if possible!) 

[Steve Swan]

I had the 4 throttle slide adj.screws plated.