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Messages - exvalvesetdabbler

Pages: [1] 2 3 ... 36
1
CB500/550 / Re: Good source for replacement screws, nuts and bolts
« on: August 10, 2026, 02:41:45 PM »
https://jis-fasteners.com/

https://www.japanmotonuts.com/product-page/copy-of-jis-screw-pan-head-zinc-white

2
CB350/400 / Re: It’s all about the timing
« on: August 08, 2026, 09:12:50 PM »
It's the o rings between the inlet stubs and cylinder head that go rock hard.

Regards
Dave

3
CB350/400 / Re: It’s all about the timing
« on: August 08, 2026, 08:59:10 PM »
It's also worth verifying you are air tight in the induction side,  inlets stubs onto the head, rubber bits both side of the carbs.

Sometimes a slight squirt of wd40 around a suspect joint will cause the engine note to change if there's a  suction leak.

Also the screws for the vacuum ports, is there a soft washer under them?

Regards
Dave

4
CB350/400 / Re: It’s all about the timing
« on: August 08, 2026, 06:34:08 PM »
Static timing using a lamp with ignition on or  measuring resistance across the points with ignition off  has always served me well so long as you're rotating the engine the right direction when approaching the break point.

A timing  light is good verification of initial timing and then checking for smooth operation of the advance mechanism up to full advance.

If your timing strobe is like mine where you clip onto a plug lead - don't melt the cable on a hot exhaust!

I did play around with timing once and noticed that  mine  ran better using about 1-2 Deg advance with the F mark. Also noted on a lot of classic car forums they mention ignition advance by a few degrees for modern E5 fuel because the flame front propagates a little slower than the old  leaded stuff. Then you look somewhere else and they are saying not to bother.


Regards Dave.

5
Misc / Open / Re: How can two 10w40 mineral oils be different?
« on: August 06, 2026, 07:11:10 PM »
Worth keeping an eye on once it's back in stock

https://www.sportsbikeshop.co.uk/motorcycle_parts/content_prod/2443472

I have a store not too far away, just wait for the right price and swing by and stock up. 

Currently have this in my bike
https://www.sportsbikeshop.co.uk/motorcycle_parts/content_prod/238309

Postage is free over £25

Good old Castrol gtx is as good as anything for these old engines. Used their 15/40 for many years when most placed sold it at reasonable prices.

Regards
Dave

6
CB350/400 / Re: 400 four earth points
« on: August 06, 2026, 05:27:11 PM »
Here's what I found after trying to clean up the contacts.

[ Guests cannot view attachments ]
[ Guests cannot view attachments ]

Not sure if this can be saved

The bottom contact cleaned up ok

Regards
Dave

7
Misc / Open / Re: How damaged is too damaged?
« on: August 06, 2026, 11:40:08 AM »
Top work Ken.  My patience would have ran out and it would have been tossed back in the spares box.  On the other hand I'm a hoarder who doesn't chuck stuff away.

Tail light bracket with 3 sets of holes for mounting the number plate
Sprocket cover with a dent
Fork sliders with a few scuffs too deep for paint to hide
Plastic replica rear mudguard
Alternator housing sound but grey with corrosion

Basically all stuff that could be refurbed with the right skills and time, and this is something that we all need to get used to when NOS parts dry up.

So we'll done Ken for showing us the way.


Regards
Dave

8
CB350/400 / Re: 400 four earth points
« on: August 05, 2026, 08:54:21 PM »
Quote from: Mikep328 on August 05, 2026, 06:59:07 PM
Just curious - did you think about replacing the OEM rectifier and regulator with a solid-state "modern" component like the one DSS sells?

The standard set up is normally reliable, well it lasted 49 years.  The only advantage would be if the maximum output was more in line with battery manufacturers guidelines for sla or AGM batteries.

Regards
Dave

9
CB350/400 / Re: 400 four earth points
« on: August 05, 2026, 06:51:36 PM »
The one that's working came off a bike  with 72k recorded mileage, so we'll see how long it lasts.
The black cover was a bit crusty so might be original. Inside looks good as new.

Dave.

10
CB350/400 / Re: 400 four earth points
« on: August 05, 2026, 05:34:39 PM »
Thanks. That looks like the shop manual.  It's the bit they are bending I can't see clearly. The copy I have is probably worse though.

Regards
Dave

11
CB350/400 / Re: 400 four earth points
« on: August 05, 2026, 05:12:49 PM »
Problem solved.   

https://youtu.be/MS2DCoaTgyw?is=vlRNYS2l2ZjsI1_Q

Side note, if that voltmeter wasn't there I might have been pushing it home.  I managed on pilot light the last few miles.


Swapped out the regulator and now getting 13.5 to 14.1 on a fast idle with the headlight on main beam.  The old one would have been draining the battery at 5000 rpm.

I'll take it out tomorrow and wring it's neck on the dual carriageway and see what it tops out at.

I kind of had an idea that this is where the problem was but several minds are better than one desperate one.  Thanks all.

Gives me a free hand to muck around with the old one knowing that I'm looking for a 13.9v transition between mode 1 and 2 during a static test on the bench.

Regards
Dave

12
CB500/550 / Re: Contact breaker points
« on: August 05, 2026, 04:13:42 PM »
Quote from: Oddjob on August 05, 2026, 02:37:58 PM
It's not. The points heel is far softer and would wear away to nothing before it affected the lobe. Someone is running an experiment to see if fitted just the TEC 1-4 points would help the aftermarket 2-3 to time up correctly. No answer yet. I think the heel on TEC points are longer than aftermarket ones which allows for greater adjustment. It's a theory.

The trick used to be enlarging the oval slot on the points  base plate allow more adjustment

13
Misc / Open / Re: How damaged is too damaged?
« on: August 05, 2026, 04:08:49 PM »
You could probably have a good side hustle going on there knocking small dents from the Speedo/tacho housings.

The other one is the alternator cover badge plate, usually covered in stone chips and boot marks but they're very thin.

Dave

14
CB350/400 / Re: 400 four earth points
« on: August 05, 2026, 03:58:04 PM »
Just like to be fully prepared and there is always more than one way to skin a cat. Pictures aren't that great where it mentions bending bits.
Looking at the actual mechanics, it looks like you loosen the top contact and slide it to get the right transition point.  That also moves the bottom contact that you then need to bend to get the 15 volt limit.

Regards
Dave

15
CB350/400 / Re: 400 four earth points
« on: August 05, 2026, 03:20:43 PM »
If there is an alternative to the shop manual for the adjustment, I would be greatful  if you could share it.

Regards
Dave

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