facebook1 youtube1 twitter1 instagram linkedin1 pinterest1

NOTICE:  If you are not a free registered member of the site, you will not see the photos in the forum, and you won't be able to access our premium member content. Please consider joining our community! REGISTER AND MAKE THIS BOX DISAPPEAR!

×

Pictures Posting Not Working (12 Jun 2023)

Picture uploads is again unavailable. We are working on the problem. Thanks for your patience.

Makotosun

Re:Re:HT1 No Spark Help

  • oldyamahajas
  • oldyamahajas's Avatar Topic Author
  • Offline
  • New Member
  • New Member
  • Posts: 3
  • Likes received: 0

HT1 No Spark Help was created by oldyamahajas

Hi guys (and gals)
I can't seem to find my original thread on this; but I'm slowly making some progress or at least ruling things out I guess.

My 70 HT1 has zero spark. Zilch. Nada. I've confirmed the coil and wire are good. I think that I should be getting some level of voltage from the black wire (as shown in the image below) as it comes straight from the magneto to the coil (is that correct??). There is zero voltage there, so I'm wondering if either I'm wrong with that assumption, OR the points, condenser, or magneto are bad?




Should I try and replace the condenser? Is it still available somewhere? Or should I just punt and try replacing the entire magneto (hoping to find one with a valid points and condenser?)

If I put a test light on say any of the wires on the light circuit (headlight, etc) I see power coming... just the starting magneto side is giving me a world of pain. I really do like this bike and would love to get it running.
26 Sep 2020 19:17 #1

This message has an attachment image.
Please log in or register to see it.

Please Log in or Create an account to join the conversation.

  • Posts: 13386
  • Likes received: 9252

Replied by MarkT on topic HT1 No Spark Help

Have you tried just cleaning the points?
1963 YG1-T, 1965 MG1-T, Allstate 250, 1970 CT1b, 1971 R5, 1973 AT3MX, 1974 TS400L, 1975 RD350, 1976 DT175C, 1976 Husqvarna 250CR, 1981 DT175G, 1988 DT50, 1990 "Super" DT50, 1991 RT180, 2017 XT250
26 Sep 2020 19:26 #2

Please Log in or Create an account to join the conversation.

  • oldyamahajas
  • oldyamahajas's Avatar Topic Author
  • Offline
  • New Member
  • New Member
  • Posts: 3
  • Likes received: 0

Replied by oldyamahajas on topic HT1 No Spark Help

I did try cleaning the points (very lightly). They don't appear to be burned or corroded but I suppose they could still be bad? Am I correct in that the black leading coming from the magneto should give a voltage on kick? Test light on it (on one end) and a ground on the other doesn't give any results.
26 Sep 2020 19:35 #3

Please Log in or Create an account to join the conversation.

  • Posts: 13386
  • Likes received: 9252

Replied by MarkT on topic HT1 No Spark Help

A very brief spike of voltage when points open. Not sure it would light test light.
1963 YG1-T, 1965 MG1-T, Allstate 250, 1970 CT1b, 1971 R5, 1973 AT3MX, 1974 TS400L, 1975 RD350, 1976 DT175C, 1976 Husqvarna 250CR, 1981 DT175G, 1988 DT50, 1990 "Super" DT50, 1991 RT180, 2017 XT250
26 Sep 2020 19:49 #4

Please Log in or Create an account to join the conversation.

  • Posts: 13386
  • Likes received: 9252

Replied by MarkT on topic HT1 No Spark Help

Have you checked primary resistance with ohmmeter?

Points get an almost invisible coating on them when sitting sometimes. They can look clean but aren't.

Contact cleaner and pulling strips of white business card (uncoated paper) through the contacts until they come out clean should fix that. (open points, insert card strip, let points close, pull out strip)

Second most common problem is wire rubbed through insulation under flywheel.

Condenser would be my next guess.
1963 YG1-T, 1965 MG1-T, Allstate 250, 1970 CT1b, 1971 R5, 1973 AT3MX, 1974 TS400L, 1975 RD350, 1976 DT175C, 1976 Husqvarna 250CR, 1981 DT175G, 1988 DT50, 1990 "Super" DT50, 1991 RT180, 2017 XT250
The following user(s) Liked this Post: oldyamahajas
26 Sep 2020 19:58 #5

Please Log in or Create an account to join the conversation.

  • oldyamahajas
  • oldyamahajas's Avatar Topic Author
  • Offline
  • New Member
  • New Member
  • Posts: 3
  • Likes received: 0

Replied by oldyamahajas on topic HT1 No Spark Help

What type of ohm levels would be good for checking the points?
26 Sep 2020 20:33 #6

Please Log in or Create an account to join the conversation.

  • Posts: 13386
  • Likes received: 9252

Replied by MarkT on topic HT1 No Spark Help

Very low. With points closed, ohms should be zero. With flywheel rotated to where points open, the reading is usually under two ohms. Analog meter with an "R X 1" scale works best in my experience.

Also curious how you know ignition coil is good?
1963 YG1-T, 1965 MG1-T, Allstate 250, 1970 CT1b, 1971 R5, 1973 AT3MX, 1974 TS400L, 1975 RD350, 1976 DT175C, 1976 Husqvarna 250CR, 1981 DT175G, 1988 DT50, 1990 "Super" DT50, 1991 RT180, 2017 XT250
26 Sep 2020 20:41 #7

Please Log in or Create an account to join the conversation.

  • Posts: 9
  • Likes received: 3

Replied by SuperKev on topic HT1 No Spark Help

Hi guys, Did you get to the bottom of this?
I’ve been rebuilding a 70 HT1 and I have a wicked spark, until I wire up the flasher unit and connect the ground,
02 Dec 2022 13:36 #8

Please Log in or Create an account to join the conversation.

  • Posts: 472
  • Likes received: 304

Replied by adguy2112 on topic HT1 No Spark Help

I don't know about HT1 model but are you connecting to the black test lead that comes out of the loom on some models near where the coil connects in? I don't think the HT1 came with turn signals as original equipment.
The following user(s) Liked this Post: MarkT, Ht1kid, SuperKev
02 Dec 2022 16:05 #9

Please Log in or Create an account to join the conversation.

  • Posts: 1361
  • Likes received: 794

Replied by Ht1kid on topic HT1 No Spark Help

Adguy is correct it didn’t come with turn signals if that’s the flasher you are talking about 
The following user(s) Liked this Post: YamahaForumUsername
02 Dec 2022 16:50 #10

Please Log in or Create an account to join the conversation.

Moderators: yamadminMakotosunDEETVinnieJames Hart