CB500 Timing marks - what's what?

[StPeter]

This may seem a dumb question but I've always believed that you can open your mouth and appear dumb or keep it shut and stay dumb . . .

I've been working my way through a basic service and have come to the timing. The consensus seems to be that static timing is the way to go and a strobe just gives you the reassurance that your advance is working. I've set the points but when I come to the static timing I'm not sure of which of the marks I should be using. Correct me if I'm wrong . . .
In the first pic, The "T" mark is the one on the left and is TDC for No 1 on compression stroke.
The "F" mark is the one on the right.

Why I'm confused is that the guide here http://www.sohc4.net/index.php/troubleshootingignitions-gettingtothepointsontime/ shows the other set of marks lined up (see the second pic).

Please can someone explain which mark is which and what the others are?

[StPeter]

Thanks for the confirmation, OJ. I feel marginally less dumb today!

[StPeter]

Spoke too soon, I think.
I've timed up 1 & 4 - it was too advanced (halfway to the max auto advance lines). When I try to time up 2 & 3, I have swung the points fully clockwise on the back plate but the points are still opening too early. Surely something wrong.

Any contributions from you advanced guys to help me feel less retarded would be much appreciated!

[StPeter]

I've no idea - they came with the bike! Good point (no pun intended) I'll pull them off and have a look. Probably best to replace them anyway.

The odd thing is that the bike was running - albeit a bit rough. No 4 pipe wasn't getting as hot as the others and a service was well overdue. I was going to check the electrics before I ripped the carbs apart. I thought I'd found the problem when I found No 1/4 static timing was about 15deg btdc. The best I can get is No 2/3 to about 10deg btdc. Obviously it doesn't like this 'cos it won't start at all now. Boogger!

[Bitsa (Ralph Wright - RIP)]

Hi,
Only my opinion but if you do change the points get the real ones pattern just ain't worth the bother.You might also want to check the base plate some pattern ones float about a bit and naffs up the point gaps.There is a thread on the 750 board with the same problems you are having.
All the best
Bitsa

[Bitsa (Ralph Wright - RIP)]

On the 750 board its listed as timing problems started by UKROB,take a look might be of help to you.
Cheers

[florence]

I've noticed that the points that are available nowadays cannot be set to the correct timing if you use the standard points gap of 14 thou.  I usually have to set them a lot closer otherwise the points do not close. 

If anyone knows where the correct set can be obtained I would be delighted.

I will say though, it is surprising how far the timing can be out without much noticable difference.  After a while my bike starts to have a misfire and runs a little raggedly.  After a few months of cursing I actually get around to checking the points and usually find the timing to be out by miles due to points wear and pitting etc...without ill effect I might add.

[z1100r]

My road bike is using the original 1975 points. Its done most of the 70,000+ miles using them.

I tried electronic ignitions when racing, 3 in all, but all conked out for various reasons. In fact I have a draw full of the good bits that remained. The last 1 blew up because Pirahna reckoned I left the ignition on too long without the engine running.

I bought a new set of Genuine points in 1998 for the road bike, but never bothered fitting them. Its had  one new condensor due to wiping one out crashing when I had too use the points plate off the road bike for racing (new centre bolt aswell).

[Bitsa (Ralph Wright - RIP)]

Hi Florence.
According to CMSNL they are same part numbers as the 750 which are still available.If they have them pretty sure DS has them too.
Not cheap though in my opinion you get what you pay for.
All the best
Bitsa

[LesterPiglet]

Florence.....

http://www.davidsilverspares.co.uk/CB500K1-FOUR-1972/part_61621/

They also have pattern for a fiver.

[StPeter]

OUCH! In 1975 that was a week's take-home - yeah, old git and all that. Guilty as charged.
Bitsa, fully appreciate the cash/quality tradeoff - as demonstrated by z1100r. There are a couple of Yankee sellers on ebay who are a  more competitive than DS. I'll get some from them. I have to make some concessions to my imaginary budget! OE should work properly. It did when the world had yet to hear of Sid Vicious. I haven't had enough brave pills to deviate too much from the Honda party line.

Previous general experience on infernal combustion engines has taught me that replacing, plugs, points, condensor, rotor arm, disti cap, plug leads/caps, coil . . .  mostly in that order, hasn't cured the fault in question. Adjustment was normally the answer - the replacement just eliminated a (very small) possibility! Still, someone wins the lottery most weeks so I'll press on!

Z11, your 1998 set of points have probably shown better % growth in value than your house.

Thanks for your comments, all. Much appreciated.

[StPeter]

On the 750 board its listed as timing problems started by UKROB,take a look might be of help to you.
Cheers

Forgot this one - sorry. Couldn't turn anything up via the search function . . .  either via "timing problems"  or UKROB. I've had problems searching on this site in the past, though - at one point the search couldn't find anything related to "clutch". Wierd!
Anyone got a link to Bitsa's reference?

[StPeter]

Thanks, Oddjob!
Don't know why I couldn't find it via the search. I think I'm suffering from poor feng shui this week . . .

[StPeter]

Update on timing problems  - and confirmation of collected resident forum wisdom

I got myself a set of genuine Honda points. They timed up nicely with settings somewhere in the middle of the adjustment range. The bike fired up and runs much better - there's a surprise! Stick to OE kit here seems to be the motto.

Thanks again for the guidance, guys.