my bonnie isn't feeling good

[bonniegirl]

hi all... my bike isn't running, or to be more specific she's running very very poorly and we need some diagnosis assistance. the history:

about 2 months ago I was pulling into our back yard, hit some loose dirt while turning around and (gently) dropped her on the R side. lovel and I got her right up, no damage, parked like usual... lovel rode her to work and she spit and sputtered and backfired, especially at low speeds, satrting from stop signs etc.
these are the things we have done:
-emptied the gas and refilled with new (it had been a while since she had been ridden)
-changed out the rubbers that connect the carbs to the head. we noticed dry rot while going over things. she was "puffing" there with the backfires.
_pulled the K&N air filter, noting engine oil, about a teaspoon or so in the bottom of the filter box. took off the K&N, put a clean stock filter on (didn't have the stuff to clean the K&N here)
-checked the plugs and noted a quite a bit of dry black yuk. got new plugs but have not put them on yet. they were probably 6-7 years old. my bad, she had a top end rebuilt and valve adustment 3 years ago and figured (foolishly I guess) that they'd change the plugs.

I still think that it's an air/fuel issue, but lovel is leaning toward electrical now.
she ran like a top til she got dropped in the back yard
2002 with 55,000 miles, airbox removed, running with bub pipes.

lovel is going to do the plugs this wknd, I have to work...
any other ideas?

robin

[mark]

Have you given the carbs a thorough cleaning? That's where I'd start.

--mark

[matts1050]

Maybe run a can of Seafoam through gas tank -better the less gas is in there.

[bonnevillebilly]

hey Rob and Paul,

My best guess is it's the ignition coil.
The symptoms sound very familiar .
I chased the same thing at slow/low speeds but, she seemed to run ok at higher rpm's
First check that all connections are good.
The coil is not cheap. If you could find another coil to try would be the best way to check.
I got Marty to let me try his coil in my Bonny and BINGO!!! that was it.

Good luck

Looking forward to seeing you guys

Bill

[LoVel]

While replacing the plugs I checked the wires. The left side wire almost fell out of the coil. I stuck it back in the coil and pulled back out with almost no resistance. I squeezed it to make the plug/clamp thingy a little smaller and stuck it back in there. On the test ride it ran much better but was still a little wonky. I am going to pull the wire back out and resize it yet again. Hopefully that will fix it. I will let you know.

[Billbikes19810]

Have you verified it's not a stuck float?

[LoVel]

I have not opened up the carbs yet. I'm thinking when I go that route I should have new gaskets on hand since these are probably 14 years old. Will be ordering some soon if the remainder of the electrical testing is unsuccessful. Will be checking spark plug wires and coil today with the meter thingy.

Last test ride it still had hiccups but they were throughout the rev range and at steady throttle.

[LoVel]

Ordered new spark plug wires today. One of the wires gave me three different readings on the multimeter. It does happen to be the same one that was extremely loose when I pulled on it.

First it read zero. Then it gave me a high reading of 12. something. The third time I checked it I got 5.5 which is close to what it should be.

The readings on the coil were in spec.

Hope this works.

[bonnevillebilly]

Hey Paul

The coil on my bike and the coil on Marty's bike both tested the same, both winding were good.
Both coils were stock coils.
But I put Marty's coil in and she ran beautiful, she didn't skip a beat.
I put my coil back in and she would cough, spit, fart and then burp at low rpm's before she would get up and go.

I bought the one New Bonneville carries, and she has been running great.
I went through the whole fuel/air system for a whole riding season before I look at the ignition system.

again, good luck

I'm getting ready to do the valve adjustment on my Bonny, it's been about 30.000 miles since I last did them

[LoVel]

I was afraid someone would say that. Well heck if the plug wires don't fix it I will order one of those. Needed new wires anyway.

[mark]

For what it's worth, I had to replace the coil on my Bonnie too; also got the one New Bonneville carries (Nology). In my Bonneville's case, it ran fine once it was running, it was just a bitch to get it started if it was less than 65 degrees out. It took me a long time to notice because the Bonnie has always been a cold-blooded beast, but I used to be able to get it started even if it was in the 30s. It would take several pokes at the starter button, but it would start. Over time, I guess the coil weakened. Anyway, installing the Nology coil fixed the problem, and now my Bonnie is back to where it's just a pain in the ass to start if it's 35 out, not impossible to start.

It would probably help if I rode the poor thing more...

--mark

[LoVel]

Just found out my dad has a spare coil at home. At least I can test it before purchase If the wires don't fix it.


I may buy a new coil anyway even if the wires do fix it.

[bonniegirl]

thanks for all the tips. poor girl is just getting a little old and parts are starting to go. she also doesn't get ridden as much as she should...
we both have the wknd off and the weather is supposed to straighten out. hopefully the plug wires will get here.
paul also ordered speedo stuff for the front wheel. we've replaced the speedo and cable and the thing still jumps like crazy, bounces all over.
we are back down in the teens here...for the ovenites. 30's during the day.
was I sold a bill of goods when I was lured down here??? I thought the south was warm??
we'll keep you updated.
thanks again!
robin

[Billbikes19810]

It's January. It'll warm up MUCH faster down there than up here, LOL. Good luck getting your baby going again. I know coils are a problem on these bikes. I know folks that keep a spare, just in case.

[mark]

we are back down in the teens here...for the ovenites. 30's during the day.
was I sold a bill of goods when I was lured down here??? I thought the south was warm??

If it makes you feel better, Robin, it was -17 here when I woke up this morning. And never made it up above zero all day. Brisk!

--mark