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Discussion Starter #1
2005 died yesterday while cruising at about 60mph. Cranks but will not start.
Felt similar to running out of gas. Plenty of fuel in the tank and carb.
Cleaned the carb. Still cranks no start.
Removed valve covers and everything seemed to move as it should. I lost a tappet lock nut in the intake last year, tappet fell out and the bike would still do 25mph.
Checked timing. Looked about right, maybe one tooth off but lots of tension in the chain, did not seem possible to slip.
Put the plug against the cylinder and the spark seemed weak and inconsistent.
Went through the supplemental manual did resistant checks on each item. Everything was in spec. The ignition coil primary was a little high, 0.8 ohm. Just touching my leads together I measured 0.3 ohm, so maybe it is ok.

Is there a diagnostic for the cdi? I hate to admit, I even tried a ether and nothing.
Cranks,cranks,cranks -- nothing. Every once it a while it will for real backfire and blows the carb off the boot. Lol.

Any help is greatly appreciated.
Thanks -- matt
 

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Post #23 in this thread...


That’s a new one for me. I’ve never heard of a backfire blowing the carb off the boot. And those intake boots are an there pretty tight. Good luck with your fix. Cheers
 

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Hey Matt,

Sorry to hear about your problems with your bike.

What does your plug look like? Is it wet with gas and can you smell gas at the tailpipe, or is it dry? Have you checked your compression?

Brian

p.s. I was born in Marysville
 

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Discussion Starter #6
Hey Matt,

Sorry to hear about your problems with your bike.

What does your plug look like? Is it wet with gas and can you smell gas at the tailpipe, or is it dry? Have you checked your compression?

Brian

p.s. I was born in Marysville
Plug looked really good. Completely dry light tan. Replaced it anyways. Spark is weak and inconsistent with each.

I moved here in 2002 after taking a job at the local automotive R&D facility. Very nice town and growing fast.
 

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Discussion Starter #7
205619

These are the electrical measurements I have taken. Are the pickup And source coil parts of the stator? Is there more to check? Should I put the cdi in the fridge?

And my tusk hand guards arrived today...

It is so nice out. Mountain bike for today I guess.
 

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View attachment 205619
These are the electrical measurements I have taken. Are the pickup And source coil parts of the stator? Is there more to check? Should I put the cdi in the fridge?

And my tusk hand guards arrived today...

It is so nice out. Mountain bike for today I guess.
I hope this makes sense and I didn't get too wordy and complicate the issue.

These problems are tricky for sure. If you think it's the pulser coil (co-located with the stator), and I can't tell you this is for sure, I had a similar experience and this is my story. Your problem still could be something else.

On the TW I'm only familiar with the ignition coil and pulser coil. The pulser coil is the one that is located with the stator. You can remove the pulser coil and leave the stator in place.

Sometimes the term pickup coil and source coil reference are other names for the pulser coil.

On my 2015 I had it quit on me while riding like you. Crank over no start. Subsequently, it happened a few other times. I found a youtube video providing guidance on the problems of testing a pulser coil. What happened in my case was when the pulser coil got hot if failed but would start when cold and this is what the guy explained in the video. Testing the wires when cold showed the pulser coil fine but when hot, not!
This is not to say your pulser coil has failed altogether. I have heard of someone on the forum with the same symptoms as yours (won't start at all even cold) and when they replaced the pulser coil the problem was solved.

A new pulser coil is around $75 which is expensive. If you don't have access to a buddy who can loan you a pulser coil, I have a new one I could send you for you to test and see if this is your problem. If it fixes it then send me money and keep the pulser coil I send you in your TW. If this does not fix the problem then send me the pulser coil back.

This is the best I can do with my limited electrical knowledge. And saying its knowledge is being kind haha. Private message me your address and I'll get it sent off in the mail this week if this interests you.

Good luck either way.
 

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I would check the compression.
 

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Discussion Starter #10
Wiped out nice on the mountain bike today. Back to the TW.

Cold CDI - no change.

I will check the compression in the morning and report the results.
 

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Discussion Starter #11
Thanks Admiral. Received the coil today.
I still need to check compression, then I will try the coil.
 

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Discussion Starter #12
Compression kit did not have a 12 mm.

Pulled the side cover off and was surprised by the amount oil.
Is that normal
 

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That's perfectly normal. Next time if you want to preserve your oil, you can just lean your bike over on it's right side.

Be very careful when you replace the side cover that you don't pinch the wiring where it exits from the crankcase/side cover.
 

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Discussion Starter #18
Replaced the intake valve, guides, tappets, piston, and gaskets.

The timing chain was a pita to get back on the lower sprocket. I straddled the bike and fiddled with the chain while the neighbor boy turned the bottom end and looked inside with his iphone.

I rewarded him with the first ride around the block.

Thanks for the help. This is a great forum.
 

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Hey Worms,

Did you do this head work yourself and what did the parts cost you? I have several heads with broken valves but wasn't sure if I could tackle the rebuild job myself.

Brian
 

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Discussion Starter #20 (Edited)
Hey Worms,

Did you do this head work yourself and what did the parts cost you? I have several heads with broken valves but wasn't sure if I could tackle the rebuild job myself.

Brian
Hi Brian.
The parts were about 350 from partzilla. That included a new pulsor coil to ship back to Admiral.
A machinist at my works fab shop took the head apart and re assembled the valves. He also cleaned up the damage in the head that was caused by the broken valve seat or the tappet nut. He was amazed at how clean the cylinder walls were and he polished them. I used a standard size piston.

He tried to do this pro- bono ( I am not his supervisor). I gave him $200 because I rushed him to then let it sit while I took a vacation....

If I had extras I would like trying to do this myself. I looked at ebay, but am a little gun shy for used parts online...
 
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