Topic: Why Are my Points Breaking/Snapping??

[Green Goblin]

Here are some pictures of the points cover.  It looks like the problem hasn't gotten any worse, so I think the few whacks I gave it with a hammer may have massaged it enough to keep it out of the way.  I'll be able to tell on Monday when I go for a bit of a longer ride.

[trueblue]

I have seen points break before, but it was in an old 40 series landcruiser, the problem with it was the distributor shaft bushes were badly worn, how it broke the points I'm not sure, but I fitted new bushes to the dizzy and it hasn't had a problem since.  It is possible there is excessive wear in your spark advancer unit causing your points to break. 

[Terry in Australia]

I'm surprised that the more "experienced" guys here haven't seen CB750 points break, ("contact breakers" is the technical term, ironically) I have raised this many times when arguing the benefits of electronic ignitions.

I was riding back to Melbourne from the Bathurst Easter TT in 1981 with my friend Pete, we'd had a great weekend and had ridden around 1000 miles when Pete's bike started running on two cylinders. He pulled the points cover off and one of the points arm's was broken just like that one. (although I think it was for cylinder 2&3, not 1&4)

Pete had serviced his K2 before our trip so luckily still had his old points plate in his bag, so after around 30 minutes he was back on the road again. The points plate was a good quality one from his local Honda dealer and the other breaker arm looked fine. His dealer gave him a new one and when pete asked if they'd ever seen this happen before, the parts guy said, "occasionally".

Pete installed a Martek 440 electronic ignition shortly afterwards as he didn't want to risk breaking down in the middle of nowhere with a buggered ignition. I guess that's kind of ironic too? Cheers, Terry.    

[Green Goblin]

Well it looks like the problem has been solved.  I purchased a good-used points plate off ebay and installed it on Sunday.  I went for a ride, about 60 kms (37 miles) round trip and took the points cover off to see how everything was looking.  The points are showing ZERO signs of damage, and the bike seems to be running well.  I went for another 40 km ride later in the evening and again, everything went well. 

I still don't know exactly what the problem was, as the points plate looks to be straight.  I'll check later in the week to see if it was a different brand than the one I replaced it with.  The old plate is at my friend's house, as the bike died on me and his garage was a closer walk than taking it to my place.

Thanks again for all of the help guys, hope everyone's riding season is going well.

[lucky]

I'm surprised that the more "experienced" guys here haven't seen CB750 points break, ("contact breakers" is the technical term, ironically) I have raised this many times when arguing the benefits of electronic ignitions.

I was riding back to Melbourne from the Bathurst Easter TT in 1981 with my friend Pete, we'd had a great weekend and had ridden around 1000 miles when Pete's bike started running on two cylinders. He pulled the points cover off and one of the points arm's was broken just like that one. (although I think it was for cylinder 2&3, not 1&4)

Pete had serviced his K2 before our trip so luckily still had his old points plate in his bag, so after around 30 minutes he was back on the road again. The points plate was a good quality one from his local Honda dealer and the other breaker arm looked fine. His dealer gave him a new one and when pete asked if they'd ever seen this happen before, the parts guy said, "occasionally".

Pete installed a Martek 440 electronic ignition shortly afterwards as he didn't want to risk breaking down in the middle of nowhere with a buggered ignition. I guess that's kind of ironic too? Cheers, Terry.

I worked in a dealership. Never saw a set of broken points.