Honda-SOHC

Picked up a 1980 CB250RS Single this week. Always fancied one since I saw the restored one in Classic Mechanics a few years back. Been off the road since 1991 and spent the last few months under a tarp outside. Taken off the road  because it had burned out a valve and done 50k miles. A bit of a change for me as my latest year model bike is a '75 CB400F .. But I had to save it! 

Like most of my bikes I got the silencers before getting the bike and had these made directly by Brituro, rather than from David Silvers.  We literally chucked the bike in the back of my mates van on Thursday and I won't have chance to fully asses it until I go to my mates warehouse (where I do my painting) on Wednesday. Even though the bike comes with a spare head, in unknown condition, I bit the bullet and bought a NOS head with valves inlet rubber etc, plus a NOS cover with the rockers etc. fitted and NOS cylinder barrel. This should hopefully save me a load of grief. I picked up these bits today near Easingwold York and the seller included a surprise freebie pair of wheels and a spare seat. The bike comes with a spare set of wheels (and CDi) but I suspect that these freebie wheels are in better nick and the spokes with replate fine at home. I bought a lovely crank and gearbox/selector parts from DK but the b*ggers have lost one parcel with the gearbox bits in it It is shown as being in transit via DHL but oddly no tracking given. They refuse to discuss this over the phone and will only communicate via eBay messaging. I wanted them to ship everything together but they refused, saying one part may possibly damage the other in transit.

The great thing about this model is that there is hardly any chrome on it and I now feel confident enough to paint it myself in pearl blue original colour. Piki on here is kindly supplying the decals although I am going to paint the stripes myself.

Laverda Dave has been a  fantastic source of help to me on this model and has some spares to trade. Thanks Dave !  If anyone else has decent parts then I will pay a decent price.

I bought a late version of the parts book for £20 in fantastic condition and I hope to scan it sometime and share with others in my Dropbox links. It  covers the early and later e-start models.

Feast yer eyes on these NOS top end parts ... they don't come along every day of the week ! Cost ££££ but it's only money. Pics of the bike to follow but be warned it's not at all pretty 

Anyone any ideas on the original finish on the 400F generator cover.

The part is stamped 333 on the inside, which is the 350F part ref. and I know that the 350F one was clear coated. However, I am not convinced that the 400F was the normal silver lacquer and was deffo not just clear coated polished alloy (like the 500/4). Attached is the 377 400 part NOS from DS.

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The next image is from the 'Push Miles' F2 auctioned off a while back. However, not convinced that the bike was truly an unmolested original.

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CB500/550 Main Bearing Shells x 4 13318-323-000 Genuine NOS In Honda Packing.

Bearing 'D'  Yellow

 £48 for the four plus £4 postage


NLA from Honda and neither DS or CMS have any stock.


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Saw these if anyone looking for used genuine downpipes

https://www.facebook.com/marketplace/item/1588480684839007/?ref=marketplace_profile&referral_code=undefined

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I had a whole bunch of Honda rear brake rods re-zinced last year and hard to identify some of them as they look pretty similar in a few cases.

Can anyone tell me the overall length of the 400F one please?

Trying to match keys to ignition and early steering lock (NOT the Nieman type as fitted to CB400F) and seat locks. So one key fits everything.
I managed to remove the tumbler pins and springs for the old style steering lock and pretty sre I can adjust the three pins lengths  to sit an ignition key.
However, not so sure how you get access to the tumbler pins on the 400F type seat lock. Anyone done this?

I found on my 400 renovated in 1986 that I had used a new rear sprocket (pattern but with wrong cutout holes) and drilled and tapped it M6 to fit the sprocket chain guard ring with domed cap screws. I had painted the ring in black 'PJ1' style paint.

Fast forward to last week I found that  I had a spare original rear sprocket guard ring, which I had attempted to have plated in the original finish (Zinc plated with a really dark green zinc passivate) but it had somehow got splashed with something during 'storage' and the finish was ruined  .  I remember having it re-plated by Allenchrome in Pocklington but they no longer do small-batch plating for bikes etc.

I dug out an original but all over slightly corroded, original compete 400/4 rear sprocket, that I got with a batch of stuff from the estate of an elderly Chinese gentleman down 'sarf' . Story was that he had bought the remains of a 400/4 from 'The House of Wheels' in Leytonstone'  (anyone remember them in the '70s  )  that had been crashed with only 600 miles on the clock (Kettle738 got the engine and sold it to a guy in Lincolnshire .. no not Trigger or Julie!). So I set about renovating this '600 mile only' sprocket to use on my 400F.

I decided not to de-rivet the guard from the sprocket. I de-greased it and  masked the exposed parts of the alloy rivets with thick paint and then dunked it in acid to remove the old plating (i.e BZP on the sprocket and the olive drab passivate on the the guard ring. After cleaning all of the remaining corrosion and a dip in 'acid salts' as used in home plating kits, I bright zinc plated the whole assembly and it turned out surprisingly nice as it's a beefy old bit of kit to home electroplate (about 7 amps plating current). I usually restrict home electroplating to much smaller items and send the big stuff out. However, this is a prime example where a commercial plater typically  wouldn't plate anything riveted together with aluminium and where DIY plating comes into it's own.

Next step it to mask off the sprocket so I can finish the guard ring. I mixed up some dark grey etch primer pigmented with green to match the original olive drab colour of the Honda part and I will spray the ring with it. Next I will apply a really thin layer of the Mipa clear-coat I used on my alloy hubs with some matting agent / reducer in it. Will report back show pic's when it's done.

This style of sprocket , .. i.e. with riveted on guard ring .... was used on the CB250/360G5 as well. Not sure about the later model CB550/750's

Just wondering what others on here do as there are some pretty picky 400F members on here?  I know DS sells repro's but they are around £120  described as 'one for the purist' .. well the purist here says that the ring finish on the DS one looks mighty like black colour (paint?) to me, not dark olive-drab like the original.

https://www.davidsilverspares.co.uk/CB400F-SUPER-SPORT-FOUR/part_346752/