Topic: Are these points done for?

[Mod Newb]

I'm a new mechanic....yesterday my bike started missing on cylinders 1 and 4.  Sounds like an ignition issue.  I've never dealt with points before, so once I did a ton of research and got over my fears I headed down to my 77 cb750 to see if I couldn't find out what's going on.

Pulling the points cover was easy enough, but I did notice that there wasn't any sort of gasket beneath it.  Isn't there supposed to be a gasket?

I looked at the points.  All of the point faces looked pale gray and each had a dot in the middle of the face.  Upon closer inspection, the 2.3 points had a shiny metal dot, and the 1.4 faces had more of a small pit.  See attached photos.  I also noticed that the fixed point and the rocker arm point on 1.4 didn't line up directly.  The rocker arm was able to move a bit so that it wouldn't be in direct alignment with the lower point.  Sounds like a problem with the cheap "Daiichi" points I've been reading about, but I can't tell who manufactured my points.

I started filing away at the fixed arm of 1.4.  I got rid of all of the gray and made it all shiny.  I started working on the rocker arm of 1.4 and kept going and going, but I couldn't get rid of the pitting.  I didn't clean the 2.3 points, because if I have to replace one, I might as well replace both.

I checked the gaps, and 1.4 had a slightly narrower gap than stock.  Maybe that's why it was pitted, and why cylinders 1 and 4 were missing.

So my question for all y'all is...Are my above assumptions correct?  Do I need completely new points, or can I make the ones currently on the bike work with a little more elbow grease? 

If I need new points, then maybe I'll  just switch over to a Dyna-S ignition.  If the points will be okay with a little bit of work, then I'll give good old HondaMan a PM and ask for one of his ignitions.  I'd prefer to support HondaMan and this forum, but new Honda OEM points and the HondaMan ignition are pricier than the Dyna-S.

[Deltarider]

Those points are not badly pitted and certainly fine for a transistor ignition like Hondaman's.

[Jordan]

might be a bad condenser, causes rough running, missing etc. had one that caused all kinds of sparking which will contribute to pitting and burning the points those don't look to bad to me. I don't know about a 750 and didn't see one in the photo

[OldSchool_IsCool]

Get urself a points file (talk to the OLD guy at the auto supply store) and they'll clean right up.  Sandpaper can embed bits in the point face and actually make the situation worse.  When the pits are gone, polish the point faces with a white, non-glossy business card soaked in brake cleaner.

+1 on possible bad condenser
++1 on the HondaMan Ignition Module (look in the Parts For Sale forum)

[HondaMan]

I'm a new mechanic....yesterday my bike started missing on cylinders 1 and 4.  Sounds like an ignition issue.  I've never dealt with points before, so once I did a ton of research and got over my fears I headed down to my 77 cb750 to see if I couldn't find out what's going on.

Pulling the points cover was easy enough, but I did notice that there wasn't any sort of gasket beneath it.  Isn't there supposed to be a gasket?

I looked at the points.  All of the point faces looked pale gray and each had a dot in the middle of the face.  Upon closer inspection, the 2.3 points had a shiny metal dot, and the 1.4 faces had more of a small pit.  See attached photos.  I also noticed that the fixed point and the rocker arm point on 1.4 didn't line up directly.  The rocker arm was able to move a bit so that it wouldn't be in direct alignment with the lower point.  Sounds like a problem with the cheap "Daiichi" points I've been reading about, but I can't tell who manufactured my points.

I started filing away at the fixed arm of 1.4.  I got rid of all of the gray and made it all shiny.  I started working on the rocker arm of 1.4 and kept going and going, but I couldn't get rid of the pitting.  I didn't clean the 2.3 points, because if I have to replace one, I might as well replace both.

I checked the gaps, and 1.4 had a slightly narrower gap than stock.  Maybe that's why it was pitted, and why cylinders 1 and 4 were missing.

So my question for all y'all is...Are my above assumptions correct?  Do I need completely new points, or can I make the ones currently on the bike work with a little more elbow grease? 

If I need new points, then maybe I'll  just switch over to a Dyna-S ignition.  If the points will be okay with a little bit of work, then I'll give good old HondaMan a PM and ask for one of his ignitions.  I'd prefer to support HondaMan and this forum, but new Honda OEM points and the HondaMan ignition are pricier than the Dyna-S.

Like they said above, those points are fine. They look to have maybe 3000 miles or so on them. I suspect the condensors are a different story, though, based on the fact that they are pitting in opposite directions and the "hole" is in the moving arm on the closeup: that indicates low capacitance. Old condensors leak when cold, which makes for weak spark until the engine is hot, and causes the points to pit faster and eventually burn black, which ruins them. Far too many of these bikes have old condensors.

Look to one of our advertisers, PartsNmore.com, for low-cost, adequate condensors. They work fine on stock points and with my Ignition, both. Those points would run fine with my box, but fix the basic problem before adding electronics into the mix, whether it's mine or Dyna's.

Bad sparkplug caps (or loose ones) are a common problem on the "F" bikes: they must not measure more than 10,500 ohms (with an ohmmeter) or spark troubles will develop. NGK sells new ones at most bike shops, about $5 each, for these bikes: get the 5000 ohm ("5K") variety for best results. If yours have a dull surface finish and dry, cracked rubber boots on them, they are done, or soon will be.

Also, what color are the sparkplugs? Are they white, or charcoal?

[Mod Newb]

Get urself a points file (talk to the OLD guy at the auto supply store) and they'll clean right up.

I picked up a points file yesterday at my local O'Reilly's.  I was suprised, there were actually three or four of them in the tools aisle.  I started filing down the points immediately.  The fixed 1.4 point actually cleaned up to a shiny surface relatively easily.  The 2.3 points look like they'd clean up easy too, but I spent a good half an hour on the 1.4 rocker arm point with no success.  The picture I included is after all of the filing.  It's hard to tell from the picture, but the pit in the middle is quite a bit deeper than the surrounding metal, so the file would have to take off a lot of material to make everything level.

Like they said above, those points are fine. They look to have maybe 3000 miles or so on them. I suspect the condensors are a different story, though, based on the fact that they are pitting in opposite directions and the "hole" is in the moving arm on the closeup: that indicates low capacitance. Old condensors leak when cold, which makes for weak spark until the engine is hot, and causes the points to pit faster and eventually burn black, which ruins them. Far too many of these bikes have old condensors.

Look to one of our advertisers, PartsNmore.com, for low-cost, adequate condensors. They work fine on stock points and with my Ignition, both. Those points would run fine with my box, but fix the basic problem before adding electronics into the mix, whether it's mine or Dyna's.

Thanks for the reply!  It sounds like my condensers are the culprit, or at least the first place to start.  Is there any way to test condensers with my handy multimeter?  I'll definitely hit Partsnmore and order some.

Bad sparkplug caps (or loose ones) are a common problem on the "F" bikes: they must not measure more than 10,500 ohms (with an ohmmeter) or spark troubles will develop. NGK sells new ones at most bike shops, about $5 each, for these bikes: get the 5000 ohm ("5K") variety for best results. If yours have a dull surface finish and dry, cracked rubber boots on them, they are done, or soon will be.

Also, what color are the sparkplugs? Are they white, or charcoal?

Spark plug caps are new NGK's installed last spring.  I don't recall if they were the 5K Ohm variety or not....  The plugs were a beautiful tan color.  That was one of the first things I checked, because, um, that's all I could think of that could be wrong.  Like I said, I'm a completely inexperienced mechanic.

Included is a picture of the entire contents behind the points cover.  Don't know if you can tell if condensers are bad by sight, but, just in case.

[HondaMan]

If the condensors are REAL bad, they will show some resistance on the highest ohms scale of your multimeter. They should appear like an open circuit, though. Capacitance is not simple to check with a multimeter, though. It involves using large value resistors (100megohm), known capacitance, and a stopwatch, where you charge and discharge, say, a 1uF capacitor and time it, then measure these condensors the same way, and divide the time of charge/discharge of the condensors by the value for the 1uF unit to get their capacitance value. By the time you've spent the day doing it, buying new ones was cheaper! Of course, there are instruments out there that do this directly, but I don't own one. Some riders here actually have one, though!

Filing: don't try to smooth out pits, that isn't necessary. The purpose of the file is to remove tips and smooth off the roughness from the arcing. On TEC points before 1974, there was actually a hole drilled in the non-moving point to allow air to escape quicker for faster closure at high RPM (and it worked!). The pitting would then made a nice, even "donut" of wear, which led to superior electrical performance and longer life, but it was harder to polish with points files because the surface was rounded like a tiny donut. They were changed to flatter surfaces for maintenance reasons around 1974. 

Those plug caps: there will be a tiny number printed on the side of the cap, showing "0k", "5k" or "10k". That's the ohms value of the NGK caps. I'm surprised at how many dealers' parts people have no clue about this fact...

[Mod Newb]

If the condensors are REAL bad, they will show some resistance on the highest ohms scale of your multimeter. They should appear like an open circuit, though. Capacitance is not simple to check with a multimeter, though. It involves using large value resistors (100megohm), known capacitance, and a stopwatch, where you charge and discharge, say, a 1uF capacitor and time it, then measure these condensors the same way, and divide the time of charge/discharge of the condensors by the value for the 1uF unit to get their capacitance value. By the time you've spent the day doing it, buying new ones was cheaper! Of course, there are instruments out there that do this directly, but I don't own one. Some riders here actually have one, though!

Filing: don't try to smooth out pits, that isn't necessary. The purpose of the file is to remove tips and smooth off the roughness from the arcing. On TEC points before 1974, there was actually a hole drilled in the non-moving point to allow air to escape quicker for faster closure at high RPM (and it worked!). The pitting would then made a nice, even "donut" of wear, which led to superior electrical performance and longer life, but it was harder to polish with points files because the surface was rounded like a tiny donut. They were changed to flatter surfaces for maintenance reasons around 1974. 

Those plug caps: there will be a tiny number printed on the side of the cap, showing "0k", "5k" or "10k". That's the ohms value of the NGK caps. I'm surprised at how many dealers' parts people have no clue about this fact...

Amazing post, thanks for the help.  I will definitely NOT worry about testing the condensers.  New ones are ordered and hopefully will be arriving sometime soon.  Also great info on the points and filing.  The service manuals I have don't go into great detail about points...it just says something like, "If the points are dirty, then clean them.  If the points are bad, then replace them."  Unfortunately, I don't know what good/bad points look like, and I'm not sure (until the help from this topic) how to necessarily go about cleaning them.

I checked out my NGK plug caps, and they are definitely 5k ohms...so at least I've got that going for me.

HondaMan, what is the current wait list like on your ignitions?  If I can get these points and the new condensers working right, then I definitely want to go the extra step and make them a little more....reliable.  I also like the idea of having an extra "kill" switch for security.  I lowered my headlight a bit, so my ignition switch wires are a little more exposed to any overly-interested people on the streets of Chicago...it would be nice to have that extra little secret step to frustrate any would-be thieves.  Not that anyone would necessarily WANT to steal my bike.  I mean, I would probably want to steal it if it wasn't mine and if I had a looser moral standard, but that's me.  But I digress.

Thanks again for the help; I'll update once I replace the condensers.

[spitcrazy]

I noticed on the pic of the plate that the bosses the plate lies in are "peened" to eliminate slack in the plate, as in flopping around in its mountings as you try to set gaps. Have a look folks, this is IMHO the best solution to that problem, at some point a good mechanic had his hands on that bike.

[Mod Newb]

I noticed on the pic of the plate that the bosses the plate lies in are "peened" to eliminate slack in the plate, as in flopping around in its mountings as you try to set gaps. Have a look folks, this is IMHO the best solution to that problem, at some point a good mechanic had his hands on that bike.

You're right....when I first bought the bike I took it to http://acemotorcycleandscooter.com here in Chicago for a tune up.  Chad at Ace cleaned the carbs, set valve clearances, and checked off a number of other "basic" (for him) tune up procedures to get it running well.  Included in that tune up was setting the point gap and the timing.  Seeing all of the things that were NOT taken care of it when I bought it leads me to believe that anything that has been done well on my ride is all due to Chad.

[Mod Newb]

The condensers arrived today, and I headed down to the ride and started working.  Easy enough to swap out the condensers...just a couple of screws and a couple of bolts, and I had it all put back together.  The point gaps measured fine at .012" with a little bit of friction at .013" and .014".  I hit the start button, and it fired right up, but still sounded like it was running on two cylinders...  I rode it around the parking lot, and sure enough, I wasn't getting the power that comes from all four cylinders.  But even though it was only on two cylinders I could still tell a difference in the idle; no more revving or almost dying out.  It stayed rock steady.  So at least one of the new condensers was doing its job right.

So I hopped off the bike and pulled the points cover again and looked at what was going on.  I couldn't see anything wrong.  On a whim I felt to make sure that the two bad cylinders were still 1 and 4, but come to find out.....NOW 1 and 4 are firing, and 2 and 3 are not.  The previous missing cylinders had been 1 and 4.  Maybe a bad condenser?

So I swap the condensers.  Nope, still running on 2 and 3, but not 1 and 4.  I look a little closer, and finally notice that the nut/bolt holding the condenser lead and the coil lead to the point are was loose.  I tried to tighten it down, but after a while realized that it wasn't getting any tighter.  I tried to take it off, but at a certain point on the bolt the nut just spun.  How does THAT happen?  I couldn't get the nut any tighter, but I couldn't take it off either.  If I put some slight pressure on the condenser wire so that it was contacting and, voila!  All four cylinders starting firing.

After some quick (and careful) dremeling and a trip to the hardware store I had a replacement nut and bolt.  Put it all back together and now have all 750 cc's back.

Once again, this forum has saved the day.  Your diagnosis (bad condensers) saved me from buying a ton of parts or having it sit in the shop and spending a ton on labor.  You guys are all awesome.  And now I have a much better understanding of my bike's ignition system.

Now it's time to get the HondaMan transistorized ignition.

[spitcrazy]

I am a noob too and the wealth of knowledge here has turned me from idiot to someone who will never let a "professional" mechanic touch my bike again. It's hard to find a mechanic that LOVES your bike like you do, and it shows, at least it did to me when I bought her last spring and took it to a local "expert". Keep reading and doing it yourself, so much satisfaction. My bike now ticks away flawlessly thanks to this site.

My HondaMan ignition is on order, I can't wait. We should all carry cards with the SOHC website address and hand them to other owners we see so they can too benefit from this site.

[HondaMan]

HondaMan, what is the current wait list like on your ignitions?  If I can get these points and the new condensers working right, then I definitely want to go the extra step and make them a little more....reliable.  I also like the idea of having an extra "kill" switch for security.  I lowered my headlight a bit, so my ignition switch wires are a little more exposed to any overly-interested people on the streets of Chicago...it would be nice to have that extra little secret step to frustrate any would-be thieves.  Not that anyone would necessarily WANT to steal my bike.  I mean, I would probably want to steal it if it wasn't mine and if I had a looser moral standard, but that's me.  But I digress.

I'm building a batch now, ready on Monday. If you want one with the "security" switch, those are $20 extra. I lived in Chicago during my High School years, and learned how to make these sort of things THERE... 

[1974blaze]

Old condensors leak when cold, which makes for weak spark until the engine is hot, and causes the points to pit faster and eventually burn black, which ruins them. Far too many of these bikes have old condensors.

so, hondaman, i have trouble starting my '78 cb125 after it has run (warm), could this also be a condenser? points look good. i don't fully understand what a leaking condenser would be, but when you say "cold" do you mean not run or middle of winter in colorado?

[Jordan]

judging from the errant sparking and rough running sputtering etc. I experienced, I would guess that it would be leaking in terms of electrical current, not leaking actual substance like a ballast for florescent lights leaks black stuff all over the floor or desk.

[dave500]

umm,its pointless ,go for a dyna or boyer ignition ,,or fumble around with points for ever,youll have trouble setting points up,if your questions have led you here,points are fine but need to be adjusted often,they are a thing off the past,now watch me get flamed,,,,you have to have good capacitors(condensors)you must have a timing light,,you will be told otherwise,yeah sure you can tweak points if your stuck somewhere,,err,with all due respect no offence but,err you cant.,,go electronic.

[HondaMan]

Old condensors leak when cold, which makes for weak spark until the engine is hot, and causes the points to pit faster and eventually burn black, which ruins them. Far too many of these bikes have old condensors.

so, hondaman, i have trouble starting my '78 cb125 after it has run (warm), could this also be a condenser? points look good. i don't fully understand what a leaking condenser would be, but when you say "cold" do you mean not run or middle of winter in colorado?

There's 2 things with those CB125 bikes that will do that: one is the condensor, and another is a too-tight intake valve. Check the clearance: it should be .003" at TDC on the compression stroke. The exhaust should be .003" to .004".

[1974blaze]

set the valves several times, will check again (your numbers are higher than the manual, which seems like a good idea) and maybe i should just go ahead order a condenser, they're pretty cheap.

any other symptoms of a bad condenser just to be sure?

[HondaMan]

set the valves several times, will check again (your numbers are higher than the manual, which seems like a good idea) and maybe i should just go ahead order a condenser, they're pretty cheap.

any other symptoms of a bad condenser just to be sure?

If you have a decent ohmmeter, you can try to check for leakage. It should measure as a open circuit, more then 10 megohms. There's not a convenient way to test it's capacitance, though. Generally, if it is more than 5 years old, it's getting pretty bad. The only exceptions to this rule are those condensors that are epoxy-sealed where the wire comes out: those last longer. When the epoxy begins to turn dark yellow, they are old enough to be changing value.

When you last cleaned your points, which side was the peak on? If the peak was on the bottom (ground) arm, the condensor is doing well. If the peak was on the moving contact, it is losing capacitance. The latter is usually the case.

If the points are generally burning (dark), then the condensor is just plain shot: it's hardly working at all.

[fendersrule]

Sorry to bring up an old thread again (hey, it's better than creating a new one, right?) but I had a question for Hondaman.

Working on CB450 points, but same principle. I decided to file them down with a points file that I got at Napa. After several minutes, I felt that I wasn't getting anywhere so I went out in my shop and grabbed a large file that had more teeth. It's still taking awhile, but I'm about halfway done with developing a flat metal sheen on both of the point faces.

After I'm finished, when the points close there shouldn't be any visible gap on any of the point edges, correct?

Do I need to knock out the burs with the file on the edges of the points?

I heard about finishing with brake cleaner and a business card to polish them. Is this true?

[fendersrule]

Anyone?

[TwoTired]

From a very old Motor's manual.

[Vinhead1957]

Fig 6 I have found in many cases, the key is left ON and it fries the points.  I got in the habit of using the kill switch first then the key.

[HondaMan]

Sorry to bring up an old thread again (hey, it's better than creating a new one, right?) but I had a question for Hondaman.

Working on CB450 points, but same principle. I decided to file them down with a points file that I got at Napa. After several minutes, I felt that I wasn't getting anywhere so I went out in my shop and grabbed a large file that had more teeth. It's still taking awhile, but I'm about halfway done with developing a flat metal sheen on both of the point faces.

After I'm finished, when the points close there shouldn't be any visible gap on any of the point edges, correct?

Do I need to knock out the burs with the file on the edges of the points?

I heard about finishing with brake cleaner and a business card to polish them. Is this true?

The ideal surface for the 450 is to have an ever-so-slight rounded surface on the moving point, and a very flat one on the stationary point. This is because the geometry is slightly off for those bikes, relative to the pivot arm. The 350/360 twin (and the older CB/CL77/72 bikes as well). The best points for those old ones were always the ND type, as they had a flat stationary pad and a rounded moving pad, from the get-go.

So, since the moving one can actually be removed, I often take them off completely when they are pretty old or burned, and work on them that way. Then when done, reinstall them and let the spring pressure hold your points file in between them, and drag it in and out at both 90 degrees to the backplate and as much side-to-side as you can: this will put a small flat spot in the center at nearly the perfect angle. I know this sounds a little "in the weeds", but it will make sense the first time you try it. Then, set the timing about .0145" (i.e. about one-half thousandth extra) if you can: in about 500 miles it will settle itself perfectly to .014" on the money.

Be sure, though, that the points cam on yours advancer is square to the shaft.Honda used some shims at the back to make this happen, and they usually wore out and fell off about 30 years ago. This lets the cam shift away from the L points, causing the gap to have to be set to .015" or .016" to meet the "F" mark, while the R point set ends up at .012" or so for that mark. This is not good, causes all sorts of unevenness in the Twins. You can make new shims, either at the back or the outer end of the cam: I make them from brass sheet. You want to have .006" to .001" clearance between the capture washer on the end of the advancer and the end of the moving points cam. Whne you get it just right, you will find the L points set up right on .014" gap and the R points at about .015".

[fendersrule]

Thanks for the information. I put Diiatchi points on the '74 450K7 as an experiment.

After many attempts running through the proper timing procedure, I ended up setting the points gap initially at .013. Instead of doing static timing this time around, I chose to do strobe timing. Seemed to get more power and accuracy with a strobe this time compared to the static method that I did last time. In the end, the final gap ended up being left at .014 and right at .017 after perfect strobe timing. I lastly bumped the right points down .016 and called it good.

This is after going through the timing three times, and eventually I learned that with these points I cannot set these "perfect", but I can come pretty close.

What do you think?

I talked to Steve from the Twins forum and he mentioned that if I have to file away the outer layer of the special metal on the points, then they are done for. I believe it's going to be really close on these points that I'm filing.