Honda CB400NA Superdream - new money puddle.

[McCabe-Thiele (Ted)]

Thanks for the comments, not going so well with the footrest bracket polishing. I moved from Kens Plastic wheels to my buffing wheel too soon.

Result is the edges are good but the main flat areas look like the craters on the moon. Going back to using the plastic discs is hard work as the surface is so smooth.

Not sure what to do now, I'm thinking of using Wet & Dry in a sanding block to rough it all up again, possibly 320 grit.

[Oddjob]

You need some fine flap wheels Ted, good for large flat areas. The ones you find on eBay tend to only come in 80 grit but there are some 40, 60, 80, 120, 180, 240 and 360 versions available if you know where to look. I’ll pm you a link tomorrow but they need adapting to fit a Dremel.

[Honda enthusiast]

When the surface has gouges or heavy pitting, I use a fine flat file and file it smooth, then 320 lightly, a lot of 400 and then 600 followed by a coarse sisal mop on the bench grinder with black soap...and then medium mop with green/yellow soap and finally polish with fine mop and white soap and then hand finish with solvol.

There's phone advice and mops/soaps here https://www.thepolishingshop.co.uk/

And a good powerful bench grinder like the 750 watt SIP makes things much easier..https://www.sip-group.com/product/category/106/sip-10%22-professional-bench-grinder/07650

Also get a decent respirator Ted and a balaclava plus goggles it's a dirty job and you don't want that in eyes or lungs 😊👍👍

[K2-K6]

As you've surmised Ted, likely you'll have to "flat" it with file or block type abrasive arrangement to reduce undulations in surface.

You can use one of those house decorators rubber/Cork material blocks to facilitate abrasive materials. They'll give softer edge to help work around the area that has a boss sticking out too.

Light pressure cuts with 180 grit should bring it back to flat plane first, then successive increases in grit number to take it finer.

Use paraffin or "maintenance spray" from Asda to keep it lubricated as you work, this to prevent pickup and risk of a gouge from that being pushed across the surface. Maintenance spray is cheaper than wd40 it's how wind tunnel aluminium models were hand finished a while back.

The effect you've currently got is a little like aluminium cylinder bores that use a flexible hone to remove material around harder particals in the casting, called a "Hypereutectic" tool to particularly target this effect.

[McCabe-Thiele (Ted)]

Thanks for the tips Ken,HE & Nigel.
Interestingly I've found Solvol dulls my  final Soap finish.

Ken has found a Gold Ultra fine finishing Soap.

[davidcumbria]

Have you tried these Ted ? I have found the plastic wheels work on engine covers etc but these flap wheels are effective on harder material. Very useful to have as an option


https://www.ebay.co.uk/itm/186399186277?var=0&mkevt=1&mkcid=1&mkrid=710-53481-19255-0&campid=5338268676&toolid=10044&ff=11&customid=CjwKCAiAnKi8BhB0EiwA58DA4clKHFvQARjxQTEB50xeSIXUKaILM9TJmjJBGi5p8tQA4Q0h5PAmJBoCFecQAvD_BwE

[taysidedragon]

Ted, I came across this classic bike dealer/breaker when looking for something. He has a whole load of 250 Superdream parts for sale. There may be something that you could use. See pic attached.

[McCabe-Thiele (Ted)]

Thanks TD I'll give them a ring, the wheels in the photo are reverse comstars probably for a CB250NC.

I did expect the rear drive cushion rubbers to need replacement, on removal not only were they all hard as rock, a PO had wound some sort of cloth type tape around the four drive lugs to make them a tighter fit, you can see the material in the right of the photo.

.PXL_20250117_111431162 by Macabe Thiele, on Flickr

[McCabe-Thiele (Ted)]

So during todays mild weather did my first clean of the Comstar rear wheel in an effort to clean the grime off the hub center and the back of the spokes where the Spiders have been living.

Just used some Bilt Hambler Surfex-HD to start with, revealed a sort of pale yellow colour on the inside, might be paint, might be how they left the factory. These wheels seem harder to clean than normal spoked wheels. Not used the jet washer yet, I'll persevere with an old tooth brush and the cleaner for a couple more times.

Photo is after the first clean.

. PXL_20250121_134236393 by Macabe Thiele, on Flickr

[ST1100]

...revealed a sort of pale yellow colour on the inside, might be paint, might be how they left the factory...

Likely like/similar to Alodine, zinc chromate or zinc phosphate corrosion inhibitor...

[McCabe-Thiele (Ted)]

...revealed a sort of pale yellow colour on the inside, might be paint, might be how they left the factory...

Likely like/similar to Alodine, zinc chromate or zinc phosphate corrosion inhibitor...

An old post on here has suggested the spokes are Cadmium plated on some variants.

[K2-K6]

Your examples look like all aluminium Ted. That's from details I can see in your photo.

Some were steel spokes with satin chrome and have clearly different appearance from the all alloy fitment.

Both rim and spoke on all aluminium are effectively  "forged" by rolling of that material. It makes them particularly resistant to surface cracks etc, as such forming a characteristic within their long term performance. 

Anodised to finish, again it very effectively protects the structural integrity by not allowing propagation of any corrosion points into fissure that would degrade them.

They are pretty tough and resilient generally, but I'd ideally try to conserve the original surface and not use anything abrasive on them if possible. 

The paint on internal surfaces doesn't look original. Agree it appears a proprietary type coating that could be from aircraft industry norm that's been applied.

High acid or alkaline type cleaners (road film remover ? ) can cause the anodised layer to go "milky".

[K2-K6]

...revealed a sort of pale yellow colour on the inside, might be paint, might be how they left the factory...

Likely like/similar to Alodine, zinc chromate or zinc phosphate corrosion inhibitor...

An old post on here has suggested the spokes are Cadmium plated on some variants.

"CAD" plate usually looks yellow in appearance a little like yellow passivated zinc from my experience a long way back.

[K2-K6]

Ooh, forgot, check spokes with a magnet to give binary id, steel or not 

[McCabe-Thiele (Ted)]

Thanks for your replies Nigel, the spokes must be some sort of alloy as they are definetely not steel, I tried my small torch magnet, then double checked with a very powerful aquarium magnet, zero attraction.