CB400F - My first bike

[JParty]

Hi friends,

I am UK based and made my first post about my new CB400F here http://forums.sohc4.net/index.php/topic,184902.0.html I didn't realise there was a community a bit closer to home!

I have an oil leak from the rocker cover. Is there are recommended suppliers of the rubber gasket?

On the original post I showed that the engine had been previously chrome plated and painted black on the cylinders. The prep must not have been great (and the coverage suggests it was done within the frame). I'd like to remove this and I'm still undecided if I do this (after masking) with paint stripper, or whether I rig myself up a homemade soda blaster. Would appreciate your input!

Currently I have the engine out and will adjust valve clearances. I did a compression test and seemed decent. Is there any other 'health checks' I can do to be sure I'm not better waiting to tidy the engine externals when I've done a full strip. Ideally I avoid this as the engine runs well.

[Nurse Julie]

Hi and welcome to the Forum, I'm pleased you found us.

[mike the bike]

Welcome to the 400four forum.   A rocker cover leak is no big problem.
Remove the cover, clean the groove and gasket and refit it if it's not damaged.
I might have a spare if you're stuck.

[Athame57]

Hi and welcome 
I started out on the US forum too, nice people also. Good luck with your restoration and here is a great place for help.

[Laverda Dave]

If your original has flattened out DSS sells genuine spares:

https://www.davidsilverspares.co.uk/CB400F-SUPER-SPORT-FOUR/part_3406/

Make sure the 'pips' in the gasket are in the correct place when fitting. You will see two indentations in the grove where they sit. And yourself a big favour, apply grease to the gasket once in otherwise it will fall straight out of the cover when you tip it over to fit it! The socket head allen bolt on the corner of the cover might be a bit suspect, it should be a 6mm threaded bolt.
Let us know how you get on and good luck.

[JParty]

Update from the weekend!

I made my DIY soda blaster and it works a treat (although it's a bit slow waiting for the compressor to fill up between blasts). Started on the cylinder fins and it took it back to the aluminium well. The top cover, partially chromed bits and sump it couldn't penetrate however. Any advice on what paint stripper will work well and not damage the aluminium surface?

I probably have another weekend of blasting before all the old paint is off. It's a bit of a shame because whoever prepared the paint before me used a pretty aggressive wire brush so it's gouged the aluminium casings. I tried a fine steel wool with autosol on a sample spot on the crank case and that worked well but is a lot of elbow grease.

[Nurse Julie]

You are making good progress there. I like to be proved wrong but I was always under the impression that the only way to remove chrome that is still stuck in place is by reverse chroming. Does anyone know any different 🤔

[JParty]

You are making good progress there. I like to be proved wrong but I was always under the impression that the only way to remove chrome that is still stuck in place is by reverse chroming. Does anyone know any different 🤔

You are right Julie. The blasting doesn't get it off. An ice scrapper does get the loose bits but won't be possible everywhere. I looked into getting it de chromed but its pricey. I have left it to think about for now.

[kevski]

You are making good progress there. I like to be proved wrong but I was always under the impression that the only way to remove chrome that is still stuck in place is by reverse chroming. Does anyone know any different 🤔

Nitric acid 69% in an electroplating bath, licensed users only, it's what i used to do for a living, aside from that elbow grease and wet and dry paper for the parts that have not already peeled.

[JParty]

Update - got carried away in lockdown. Now time to find a blaster and painter near Milton Keynes!

Separately - starter motor question:
I noticed when the bike was assembled, sometimes when I kicked it with the kick starter I noticed on some kicks it felt like the starter was engaged (adds quite a lot of resistance). In another instance, I had one case where when the battery was connected and the starter engaged and started turning straight away (no key in and ignition off). Sprayed some contact cleaner near the switches and left it to rest. Connected battery again and didn't cause issue but it doesn't make sense to me.

[Bryanj]

Starter turning with key off means the solenoid was stuck in