Honda CT70 - no spark

This video walks thru the steps I took to diagnose a “no spark” issue. #HondaCT70 #Honda #Trail70

[@eastcoastish]

It's always such a relieving feeling when you finally get an old bike to spark and get it to start. Glad to seeing you work on the original engine on this one 😁

[@jupitercyclops6521]

I hate auto electrical issues

[@MiniBikeMike]

Agreed. I’m just going to flip this one, so it will stay stock.

[@michaellee6762]

@@MiniBikeMike I'm having the same exact issue with my 71 Yamaha G5 trailmaster. Got it running previously and returned it to its owner, sat for acouple weeks and now...nothing! The kicker for the starter (its splines) were just about stripped so I've been popping the clutch and started right up. Now... when I remove the spark plug, its soaked. It ran so well too when I had it running. Wish I was better at life...lol

[@gabhayasinghe8688]

Your vedeo is great

[@Oldtimeytools]

Just bought the same bike, in red too! No spark. This is invaluable advice thank you

[@dyske-]

Thank you for taking us along for the ride! I enjoyed watching the troubleshooting process. I had the same reaction as you did when you got it to start! Take care!

[@MiniBikeMike]

Thanks!

[@82em1]

Well now i know how to trouble shoot without taking everything apart!! Thanks Mikey!🤘🏽

[@MiniBikeMike]

Thanks for watching!

[@TMichaelJKnivestmichaeljknives]

Gotta love the excitement when it fired up. Great vid.

[@denisthek]

Thanks so much for one of the best videos I have ever seen. So much for if it has flywheel magneto you (DON'T NEED A BATTERY) this is ture but if you don't loop the to black wires together at the battery it's going to be open circuit and no run. Thanks for teaching me that you can have a the light show points open and close and voltage. I would have put down money that a bad condenser would not show voltage, because it would have gone to ground. Thanks again for a really good video and teaching me what the to black wires at the Batt. are for and what a great test point it is. Sincerely Denis Kerechuk.

[@yokomzare201]

Always look forward to Your Videos on these bikes. Thanks so much. Carry on.

[@MiniBikeMike]

Thanks for following along!

[@noahrost5694]

Super helpful in a number of ways thanks!

[@bartgoins1782]

Great video! Yep, I learned a bit about diagnosing the lack of spark. Glad I found your channel.

[@MiniBikeMike]

👍🏻

[@ea4063]

Thank you for showing us how to take care of business, now I am your subscriber.

[@MiniBikeMike]

Thanks!

[@stevothegreat]

Good job of tracing the problem !, some of my bikes have electrical problems due the age of 30 ,40 years .Usually the connections of wires are corroded to the point that currents can`t go through , high resistance. Looks look the moisture must have got in the codenser area with that white powder formed. Perhaps gaskset got weaker around the cover which could have break down to let moisture form. Good job and thanks for showing the video. Always i learned alot from your videos on maintaining these gems !

[@MiniBikeMike]

Thanks! I’m going to guess that the condenser was probably good, just a bad connection. It came loose very easily.

[@my50bike]

Having issues with a few Dax in the garage with no spark... this has helped me a great deal thank you! I have spark on a few still battling with a few but just realised my health and safety battery charger does not work unless connected to a batter :-) will have to go find an old-school one somewhere...Why they needed to put the coil where it is on these bikes is beyond me ;-)

[@MiniBikeMike]

I’m not a fan of these new safety chargers. And agree, the coil placement is a pain. 😂

[@Bradleytlohman]

So enjoy your channel! You have helped so much

[@MiniBikeMike]

Thanks!

[@reggydunlop5770]

Very informative. Thanks Mike

[@heydonray]

Learned a lot. THANKS.

[@205dante]

Amazing video Mike! You should keep the original engine on this one. :)

[@MiniBikeMike]

Definitely keeping this one stock. I typically only install a Lifan if the original engine is missing or has a serious failure.

[@dougdavault4256]

Good video on troubleshooting for spark . Video on rebuild stater keep this bike with original motor thanks again amazing video

[@MiniBikeMike]

Thanks! Yeah, I’ll sell this one with the original engine.

[@solonwoodall1330]

Great video!!

[@tomnix1941]

You saved my day..I now can trouble shoot my ct70..Thank you so much for your video! also want to say I subscribed to your channel and gave a thumbs up !

[@levylovits]

Hey mate ty i confirm the magneto is working. Next would be coil for me

[@mikeangelastro7648]

Great video….thank you!🇺🇸

[@MiniBikeMike]

👍🏻

[@mmetz1877]

Helpful video, thanks!

[@MiniBikeMike]

👍🏻

[@marioruiz5313]

Mike "Merlin" doing his thing 🧙‍♂️🎇

[@MiniBikeMike]

😂

[@mikeb6431]

Excellent troubleshooting video Mike! Be thankful I'm not close to Indiana! I could learn so much visiting with you! LOL!!!

[@MiniBikeMike]

Thanks! I’m always down for visitors.

[@unclemoki6502]

Great video. Working on my first CT70 K1 and this was very helpful. Question about the black jumper on the pigtail - I picked up a new wiring harness from CHP and there seems to be continuity between the black stator wire and the black ignition coil without the need for the jumper. Found an old wiring diagram and it shows that the jumper should be the only thing creating continuity between the two black wires. Wondering if you’ve seen this before? Guessing it won’t hurt to add the jumper anyway but it seems unnecessary, at least with this new harness I received?

[@MiniBikeMike]

I’ve not used a CHP harness, so I’m not familiar with it, but that sounds odd.

[@Parry635]

thank you

[@jaredheywood7707]

Hey there! I have followed and passed your first 2 steps. However, during your 3rd step, checking the coil and attaching it to a 6v charger I’m getting no spark. I put the positive to the harness under the seat, spark plug up against the cylinder head, then negative to the engine case but still no spark. I need some help on what to do next. Also the coil is brand new. Thoughts?

[@Mark-xs7st]

One other question: My battery charger setting is 6V and 15 amp as the only setting. Is the amperage to much to use? Any other way to check the coil otherwise? Thanks

[@Mike-wx7bx]

Awesome

[@jeffferguson899]

good job

[@MiniBikeMike]

Thanks Jeff!

[@richarde.weixelbaumsr.4077]

So, when you put the test light into both ports on the plug and they both light the bulb (even without kicking the bike over) - I assume that means the points are stuck open?

[@KevinPatz-pn2gs]

I thought if you were getting the light to flicker on the black stator wire, this would mean the condensor and the stator is working properly? Confused as I just seen a video where guy says if your getting the black stator wire to flicker it means everything on engine is fine and to look at wiring or coil problem.

[@vernprescott7084]

Really learn thru your step by step diagnosis, how do you mouse proof the CT70's that you have sitting around. I have to keep mine in a shed and its not mouse proof whatsoever Also how can I look up the tools that you use?

[@MiniBikeMike]

Thanks. I’ve never had a mouse problem at the shop. I’ve never done anything to mouse proof. What tool are you interested in, maybe I can find a link.

[@Mark-xs7st]

Great video. Question: I did the test light test and the light does not flicker - it just stays on when cranking over. Are the points stuck together or something else? I have a flywheel puller on order so plan to take a look shortly

[@MiniBikeMike]

Yes, if the light stays on, your points aren’t opening or the points are grounded to the engine somewhere.

[@vernprescott7084]

hey Mike what brand of coil do you like? for 1970 CT70H

[@MiniBikeMike]

Honestly, I’ve never purchased new coil for an original bike. I’ve never had a bike with a bad coil.

[@heydonray]

That dirty soldering tip and wires needed some flux…

[@MiniBikeMike]

Yeah, unfortunately, I rarely work on the original engines, so I don’t keep the needed tools/equipment around. I much prefer a Lifan swap.

[@jeanjacquesfortiable]

hi I see that you use your impact to run your engine but what type of socket do you use? nice video bye

[@MiniBikeMike]

It’s not an impact, just a regular drill. I just use a standard socket.

[@jeanjacquesfortiable]

@@MiniBikeMike Thank you very much my friend ! Are you using a socket the same size as the one that goes on the stator nut or larger so as not to break the shaft threads?

[@austincannon3128]

My 1977 ct 70 shows all the same signs and I replaced the points and the condenser but still no spark? Do you have any pointers?

[@MiniBikeMike]

Have you confirmed that the coil is good and working properly? If so, the next step would be to eliminate the harness from the system. Unplug the engine and the coil from the main harness. Run a jumper wire from the black wire of the engine to the black wire of the coil. If still no spark, the problem has to be under the flywheel. Double check that the wiring and solder on the condenser are not touching the outer case of the condenser. If it is, it will ground out the system and kill spark.

[@austincannon3128]

@@MiniBikeMike man thank you that’s so helpful! You really know your stuff 😀. I ran a jumper wire just like you said, it sent a nice spark! Then I greased up the connections and plugged it all back in. And sure enough I officially have spark! Can’t thank you enough!!

[@MiniBikeMike]

Glad it worked for you.

[@franciscoolvera6871]

👏🏼

[@MiniBikeMike]

Thanks!

[@cainbeeping8480]

Maybe the wire between when you move it it might lose connection

[@scottlancaster8669]

I would like to get a bike from you how do I do that?

[@MiniBikeMike]

Which bike would you like?

[@ifitsfreeitsforme1852]

How come whenever I find these little bikes, the wiring is a cobbled together mess of electrical tape and wire nuts???

[@MiniBikeMike]

Because these were kids bikes and kids were working on them. 🤷🏻‍♂️

[@ifitsfreeitsforme1852]

@@MiniBikeMike I dunno, I've seen some grown ups that weren't capable of anything better . Lol

[@MiniBikeMike]

@@ifitsfreeitsforme1852 Not everyone is mechanically inclined, some did the best they could. I’m sure if I went back and looked at my work, when I started on these bikes 30 years ago, I’d shake my head at some of the stuff I did. Hell, I still cut corners every now and then. 🤣

[@ifitsfreeitsforme1852]

@@MiniBikeMike Yep, I wasn't a born Einstein either. I learned from my mistakes as I went along.

[@ifitsfreeitsforme1852]

@@MiniBikeMike Do you work on Aermacchi mini bikes , like Z-90s ? If I'm not mistaken, they're positive ground like British stuff

[@jupitercyclops6521]

Always remember; Lefty tighty - righty loosie (I'm lex-dysic though)

[@petervandenbrink4860]

Misschien een idee om eens één ct70 met originele motor klaar te maken kijk er na uit

[@MiniBikeMike]

Yes, definitely keeping this one original. 👍🏻

[@jupitercyclops6521]

No spark is the issue I'm having with my old trail 70.

[@MiniBikeMike]

Hopefully, this video helps you track down the failure spot.

[@gerardkenny8408]

Awesome

[@MiniBikeMike]

Thanks!