Honda-SOHC
SOHC.co.uk Forums => Anorak's Corner => Topic started by: exvalvesetdabbler on September 18, 2025, 02:24:28 PM
-
Outer case is the same as a 400F
[attachimg=1]
Regards
Dave
-
This is my CB200 (https://uploads.tapatalk-cdn.com/20250918/7ebe27cd54dcda361a827caa4b9f31ab.jpg)
Sent from my SM-A546E using Tapatalk
-
CB250/350K4 If underside looks like attached.
-
Here a view from the bottom
[attachimg=1]
Regards
Dave
-
Slightly angled drive ... so probably CB250/360 G5 also CJ model
-
Thanks Ash, if my rebuild of instruments goes to plan over the next few months, this could be surplus to requirements, it was on a scrap 400f I bought 30 years ago and kept it for spare crimp band.
Regards
Dave
-
It could be from a CB250, with the yellow segment starting at 9200 rpm.
My CB360T has a red segment starting at 9500 rpm.
and my CB500-foue is white starting at 10,000r pm.
All the segments stop at 11k and all the drives are slanted.
-
From memory I'd say CB360G, one of its derivatives.
I think that the CB250G5 had a higher red line, maybe 10,200 ?
I can remember having both in the '90's.
250 liked to rev hard, but lacking in torque.
360 had punchy torque but wouldn't rev high
-
What is that green paint I keep seeing on the back of clocks? ???
-
Some attempt at sealing against moisture or galvanic corrosion I think. Mostly see it on those that don't have ventilation holes in the base (spider access holes). Also see the green paint around the rivets that hold the heat shields for the lamps that are riveted. Later versions seem to have the spot welded lamp shields and the vent holes and no green paint.
Some also have a paper gasget between the internal frame and base.
Also have one where the black cover and inner cover is 1.5 mm shorter and different rubber gasgets
Makes mix n match of parts rather tricky.
One of life's mysteries...
Regards
Dave
-
What is that green paint I keep seeing on the back of clocks? ???
This may help, as I've seen it on other environment with instrument installations too
"Common types of green paint and associated risks
Zinc chromate primer: This was widely used on metals like aluminum, steel, and magnesium for its excellent anti-corrosive properties. It was applied to the inside of vintage electronics, aerospace, and military equipment. The green color is a key characteristic.
Health risk: Chromates are known carcinogens and can cause skin and lung irritation.
Lead arsenate paints: This is a rarer but more dangerous possibility. Scheele's Green, a pigment containing copper arsenite, was notoriously used in paints and wallpaper during the Victorian era. Its use in electronics would be a serious health hazard.
Health risk: Arsenic is highly toxic, and its flakes or dust can be inhaled or ingested, leading to a host of health problems"
Whether its has any "degausing" attribute too in these situations may be to keep cases from causing issue with spinning magnet etc, I'd not know.
-
A stab in the dark? This is on a CB350 K series.
-
Start of the red line matches.
Dave.
-
The green paint seems like oil based gloss paint, it's probably to keep moisture out the crevice between the alloy bush housing and the steel of the base and inner frame in conjunction with the greasy paper gadget inside. Same with the aluminium rivets going through the steel base and lamp shields.
Seems to tie in with fogging of the glass in cold humid conditions and that later versions have two breather holes in the base and no attempt to seal up the gap. I remember folk having to switch on the lights to demist the inside of the clocks from the heat of the bulbs if it got too misted up when temperatures dropped suddenly.
Probably Nippon fixed a problem or later versions were new and improved (found a way to make them cheaper).
Regards
Dave
-
Its off a 71,72 or 73 CB/CL 350