CT-70HK1 Ignition (again, I know. Sorry)

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TAWPTool

New Member
I have my restored (ish) HK1 and it's gorgeous! But she won't run.

I have a very weak spark. I have cleaned all grounds, new points, new spark plug, etc. I am at the end of my patience level now and am reaching out for a little help from the collective group.

Can anyone recommend something else to try? I know that these ignition parts are fairly rare on the new and used market. The CDI retrofit looks very compelling, but I have read here that it has a possible rocky success rate on the 4-speeds.

Recommendations, ideas, and suggestions are very welcome! Before I bury her in the backyard. Haha!

Thank you,
Guy
 
hrc200x

hrc200x

Active Member
Is the spark intermittent or not very blue? If intermittent double and tripple check the points. Somtimes the feeler gauge can push open the points, you need to look in the hole of the flywheel with a flashlight to make sure adjustment is being done the correct way. Set them to .012-.016 with the T strait up pointing to the notch in the case. Its possible on a 4 speed that the points cam/advancer be 180 degrees out, but that wouldn't cause weak spark, just spark at the wrong time.
 
T

TAWPTool

New Member
It is a consistent spark, just orange/yellow in color.


hrc200x said:
Is the spark intermittent or not very blue? If intermittent double and tripple check the points. Somtimes the feeler gauge can push open the points, you need to look in the hole of the flywheel with a flashlight to make sure adjustment is being done the correct way. Set them to .012-.016 with the T strait up pointing to the notch in the case. Its possible on a 4 speed that the points cam/advancer be 180 degrees out, but that wouldn't cause weak spark, just spark at the wrong time.
Click to expand...
 
ctbale

ctbale

Member
I would resist going the CDI route. I will throw a china carb on a CT70 in a minute, but I like the ignitions on these bikes. Weak is better then no spark. I have never seen a spark plug coil fail. The coil under the flywheel can get weak or fail. The points, condenser (the condensers are pretty reliable too) , the spark plug cap, a good NGK spark plug. Good grounds, corrosion free connectors, lots of stuff to check.
 
6

69ST

Well-Known Member
Condensers used to be stone-reliable. That's changed in recent years. IDK to what extent, or the reasons why. It'll be years before the former question gets answered, the latter maybe never. Suffice it to say that a lame condenser is now something worth considering. It's also the most likely ignition system component to cause a weak spark, as opposed to no spark.

Suggestions...
Clean the point contacts. A few swipes with 600-grit sandpaper, followed by cleaning solvent, should remove any potential flash rust, anti-oxidation coating, or oil. Start with a new plug, if you haven't already. If the spark still lacks normal strength, replace the condenser. In proper working condition, these old breaker point ignitions can produce spark that rivals CDI.
 
cjpayne

cjpayne

Well-Known Member
I agree with racerx. My first thought was the condenser. If it's been replaced, it may have had the solder gun held on for too long and was damaged. Make sure that the stator to magnet surfaces are clean too.
 
A

allenp42

Well-Known Member
2x on this statement.

racerx said:
A few swipes with 600-grit sandpaper, followed by cleaning solvent,
Click to expand...

Recently, I have had to spray down the points with contact cleaner before I get solid connection when the points close. It seems to be a lot worse on aftermarket points (K&S for example) than OEM Honda points.
 
T

TAWPTool

New Member
Thanks for all of your suggestions. I will methodically do all of the above one at a time and report back. Again, thank you guys.

Guy
 
6

69ST

Well-Known Member
allenp42 said:
2x on this statement.



Recently, I have had to spray down the points with contact cleaner before I get solid connection when the points close. It seems to be a lot worse on aftermarket points (K&S for example) than OEM Honda points.
Click to expand...

That's not all bad, btw. Some breaker assemblies are coating to prevent rust. Sandpaper and Brakleen make quick, easy, work of the pre-installation cleaning, before the points are screwed to the stator plate.
 
ctbale

ctbale

Member
I use a tiny points file on the breaker points. single cut file. But I usually just put new ponts in, only $10. Then cut a white index card in 1/4 strips, dip them in iso alc and when the points are closed draw the wet paper thru. gets them clean and debris free.
 
R

Roy Chambers

Member
TAWPTool said:
I have my restored (ish) HK1 and it's gorgeous! But she won't run.

I have a very weak spark. I have cleaned all grounds, new points, new spark plug, etc. I am at the end of my patience level now and am reaching out for a little help from the collective group.

Can anyone recommend something else to try? I know that these ignition parts are fairly rare on the new and used market. The CDI retrofit looks very compelling, but I have read here that it has a possible rocky success rate on the 4-speeds.

Recommendations, ideas, and suggestions are very welcome! Before I bury her in the backyard. Haha!

Thank you,
Guy
Click to expand...
Did you check the Spark Plug Cap ???
These bikes use a Resistor Cap! Sometimes they go bad.
You can check them by unscrewing it off of the wire like a Nut. Turn it counterclockwise off the wire, then using a Ohm Meter on each end of the Cap, check the Ohm's. It should be around 5K OR 5 thousand Ohm's!

If the Meter shows a Open, then it's bad! To reinstall it, or a New one, turn it to the Right and push wile turning it on the wire.

ALSO: I never Sand OR File brand new points!
Good made contact points have a Super Thin plating of Silver on them, it's so thin that you can file it right off in a few strokes.
Only File points if they show hi resistance, cause once you File points, they expect you to do it to them all the time.
Even if they look bad, don't file them if they are working OK. You can, however pull the paper through them to clean them.
Even if you just want to readjust the gap, don't file them unless you absolutely have to.

Another tip is, to set the points, use the fatcaaat method ! Look under, Modifications. increase the performance of your stock engine, post #10. OR use a Timing Light instead of a feeler gauge.

Thanks Roy
 
ctbale

ctbale

Member
using a feeler gauge to set timing never made sense to me. I do it with a meter, when it goes from .5 ohms to 3 ish ohms then you know the points just opened. should happen on the F mark. only way to know when the spark happens
 
cjpayne

cjpayne

Well-Known Member
I just set them to .016 with a feeler gauge. I have a set just for this and the valves. I made the .016 narrower with a bend at the end and the valves(.002in .003ex) with a bend at the end. Just makes it easier.

I have never had to clean new OEM points(knock on wood). If I'm diagnosing and putting new points in to maybe cure a problem, I set them to .014 just to make sure I didn't go over the limit. I'll fine tune it later.

I've had an idea for awhile now to make the cam rider piece last longer between adjustments. I thought about mixing bearing grease with Castrol syntec or some other synthetic or super lubricant. Just an idea
 
kirrbby

kirrbby

Well-Known Member
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T

TAWPTool

New Member
New spark plug - same weak spark.
Filed and cleaned the points - still no start.

I ordered a new condenser from DRATV. When it arrives, I will remove the flywheel, then all of the ignition parts and methodically clean every possible connection and grounds. If it still won't start then I will replace the condenser.

Frustrated fingers crossed.

Guy
 
T

TAWPTool

New Member
I know everyone enjoys photos so...
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6

69ST

Well-Known Member
You've all but confirmed a weak/dying condenser, at this stage. Might be worth throwing a new set of points at it, while you're into the stator assembly. Sanding/filing point contacts is usually just a temporary fix, or diagnostic tool, to be used if the contacts are rusty or worn. With new points, a little solvent and a clean rag, or paper towel, is all that's needed and then only if they've been sprayed with cosmoline (or equivalent).
 
A

allenp42

Well-Known Member
Do you have the Hitachi or Mitsubishi flywheel/stator? If you're not sure, pop the cover off and post a pic. The condenser is different for a Mitsu vs. a Hitachi.
 
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