Dies when hot Part 2

[Tim]

Could a bad coil be causing this problem? Thanks guys, your way better than the other site(s), by far!!!

[tampaFZR600]

First step would be to ohm them out...

[reelrazor]

Could a bad coil be causing this problem? Thanks guys, your way better than the other site(s), by far!!!

Not very likely.

Testing them as shown above won't tell you anything about how the coils are when they are hot-unless you do it right when the problem occurs. If you are preapred to do any test when the problem occurs it would be really easy to pull a couple plug boots and put a couple extra plugs in them and do a spark test.

[Tim]

So, process of elimination leads to the CDI (TCI). Does anyone disagree?

[Fizzinatorr]

i posted a bunch of questions in the last topics you made

check them and answer them, if all your answers are "it's fine" then i'd agree on the CDI

[Tim]

Anyone have a CDI in their closet?

[reelrazor]

So, process of elimination leads to the CDI (TCI). Does anyone disagree?

umm, kinda.

Let's see, I think I recall that you were at a point where the bike cranked but wouldn't start at all....is this correct?

If so, do you have spark? (30 second test).

If spark, forget electrical.

If it will start and run, but the problem occurs when the engine gets hot....do you have spark when it is hot?

if spark, forget electrical.

Occasionally, there will be a weird heat related ignition failure, which is easily tested for(see above) but it is far rarer than:

Engines that get hot and quit running usually have a mechanical-heat related cause. This is often valves expanding and failing to seal, or valves expanding and sticking in guides, can be head gasket seal/head warpage. Or it could be aas simple as carbon in the combustion chamber making contact with pistons while hot, or carbon on the valves expandinga nd eliminating valve seal. AND, these things often go away when the engine cools. AND, if done enough times will result in a permanent condition that will eliminate cool-down restarting.

The 'tick' you hear before the problem occurs could be an exhaust leak (which would heat up the nearby exhaust valves), could be preignition (combustion chamber hot enough to spontaneously combust the fuel air mix), or could be combustion leaking past head gasket into water jacket, or carbon-metal contact.

Any of which will make the throttle unresponsive.

That's my $.02.

I'd do the spark tests, then break out a leakdown tester and get to the bottom of this.

[Tim]

Correct me if i am wrong: I had a CDI go bad and the symptoms were almost the same except the idle would fluxuate between idle and 3500 rpms. When I put that bad CDI back in, the bike will start and present the fluxuating idle symptoms. The bike has very very low miles, I dont know if that would make a difference or not. Would this point back to the CDI? I am open to entertaining all sugestions,but i really think it is electrical. Please dont get me wrong, I am nt second guessing you. This problem is fustrating the hell out of me and has been going on way too long.

[reelrazor]

Correct me if i am wrong: I had a CDI go bad and the symptoms were almost the same except the idle would fluxuate between idle and 3500 rpms. When I put that bad CDI back in, the bike will start and present the fluxuating idle symptoms.

This bike? The one you are talking about die-ing when hot? I guess I missed that it won't run with one TCI, but will with another.

here's a page from the Yamaha Vision rider's group...it has lots of good info on TCI ignition and some test procedures..their TCI's operate excatly like ours, except they have two pickup coils to our one.

http://www.jetav8r.com/Vision/IgnitionFAQ.html#a12p0

[Tim]

Hey guys, I trust you more than EBAY so, I thought i would ask here first. SO, if anyone has a GOOD set of carbs off a late fzr they want to sell QUICK, please let me know. I would like to try and keep the price around $100.
Thanks again for all of your help and valuable advice,
Tim

[ragedigital]

Tim - I would create a post in the ITEMS WANTED forum. That might help you find a set of carbs easier.

darrin