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Discussion Starter · #1 ·
Hi, i’ve just received a set of points I ordered for my ‘71 CB250 K3 and there is no way to set them as the cam follower appears too long and is forcing the points to remain permanently open. You can see in the photo attached that when the points are closed the fixing holes are way out of alignment.

I’ve seen the CMC video about filing the fixing holes on the points bigger, but these ones are so far off that would mean filing all the way through removing all the metal.

The only option I see is to remove the lever and remove 1mm from the end of the cam follower. I’d obviously have to make sure that it is done parallel to the cam, leaving a flat surface to contact the cam with.

Has anyone else had to do this? Would this be easy to do, or could it cause other issues?

Obviously can’t send them back if I file any of it, but alternative options are a bit slim it seems.

Thanks!
 

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Appears to me they are not the correct points for your bike. Send them back.

Where did you get them from?
 

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Discussion Starter · #3 ·
I got them from David Silvers. If you line them up with the originals, they appear identical except for the cam follower part of the lever is a mm or two longer. The backing plate is a perfect match. Bit strange but the Common Motorcycle Collective sell a file with their points for you to make adjustments to the holes, so must be a thing I guess.
 

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Are you sure your spark adv is assembled correctly. Remove it and post a photo. The notch on the cam tip should point toward the arrow on the plate.
Also, your EX rocker pin is oriented wrong. Notch should be facing outward I believe
 

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I got them from David Silvers. If you line them up with the originals, they appear identical except for the cam follower part of the lever is a mm or two longer. The backing plate is a perfect match. Bit strange but the Common Motorcycle Collective sell a file with their points for you to make adjustments to the holes, so must be a thing I guess.
I wonder if DSS is aware of this, hard to believe they'd sell them if they knew... though it isn't that surprising to me that CMC sells points that need to be modified, but sending a file with them? I guess it's better than a chisel. Has to be a source out there for a better aftermarket set than this. Did you look at any of these from 4into1.com? Part number seems to show the 350 and 250 use the same points. Some are shown to be OEM, others obviously aftermarket

https://4into1.com/genuine-honda-points-left-30204-286-004-cb350-cb360/

https://4into1.com/genuine-honda-points-right-30203-286-004-cb350-cb360/

https://4into1.com/ignition-tune-up-kit-honda-cb-cl-sl350-cb-cj-cl360/

https://4into1.com/points-left-30204-286-004-honda-cb-cl-sl350-cb-cj-cl360/

https://4into1.com/points-right-30203-286-004-honda-cb-cl-sl350-cb-cj-cl360/

https://4into1.com/points-set-left-right-honda-cb-cl-sl350-cb-cj-cl360/
 

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Discussion Starter · #6 · (Edited)
Are you sure your spark adv is assembled correctly. Remove it and post a photo. The notch on the cam tip should point toward the arrow on the plate.
Also, your EX rocker pin is oriented wrong. Notch should be facing outward I believe
Thanks for your reply doode. I did the valve clearances last week to the spec in the Honda shop manual. Also did the timing with a strobe timing light and the advance unit seemed to working okay as the notch sat between the two lines on the flywheel at 5000rpm.

I will get the breaker plate off tonight and take a pic. Can you explain what makes you think it may be assembled wrong? Also, if the valve clearances are correct, how would the notch face the wrong way, and how would it affect anything? Hope i am understanding you correctly. Thanks.
 

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Discussion Starter · #7 · (Edited)
Ancient dad- Silvers apologised but had no explanation to give me. Thanks for the links to those other alternatives. Silvers does have genuine points in stock so I will probably exchange these for genuine, if I decide not to attack ‘em with a file! (The points that is, not David Silvers!)
 

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Discussion Starter · #8 ·
Remove it and post a photo. The notch on the cam tip should point toward the arrow on the plate.
Here’s a pic. The notch does point towards the arrow and the weights move out as the cam turns. What do you think... look okay?
 

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Discussion Starter · #9 ·
I’ve measured the original points from the outside edge of the points base plate to the tip of the cam follower and they were 17.59mm. The same distance on the new pattern parts is 19.51mm. The lever comes out 2mm further, so for them to work I would have to remove that extra from the end of the cam follower?
 

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Do the points for the other cylinder fit the same way?
 

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Discussion Starter · #12 ·
Okay, after some filing of both the lever and holes, and adjusting of the contact breaker plate I have managed to get the points both timed to open correctly and with a gap between 0.3-0.4mm. It’s late and the neighbours won’t appreciate me revving it with a strobe light, but I did get it ticking over nicely with a good strong spark on both cylinders, using a pair of inline spark plug testers in the dark.

I’ll be honest, I think I may still fork out for a genuine set as there was a bit too much fettling involved, but this situation is better than the old pitted pair i’ve had to bin.
 
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