Motorcycle Question Thread II: Less chatting and more questions

The Something Awful Forums > Discussion > Automotive Insanity > Cycle Asylum > Motorcycle Question Thread II: Less chatting and more questions

Ammanas: Jul 17, 2005; Voltes V: "Laser swooooooooord!"

My girlfriend signed up for the MSF, and I can loan her some of my gear. What she doesn't have are a pair of boots for the course - everyting over the ankle she has is heeled.

She basically only needs a pair of something for the course, she doesn't know if she'll actually stick out and get a bike. Suggestions - cheap & returnable? Wal-Mart maybe?

# ¿ Mar 1, 2010 07:46

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# ¿ May 24, 2013 03:41

Ammanas: Jul 17, 2005; Voltes V: "Laser swooooooooord!"

is $160 for a 01 f4i battery a reasonable price? how is it my gs500 battery cost $65, is there a hundred bucks more acid in there or some poo poo
jesus christ

# ¿ Jul 27, 2010 22:52

Ammanas: Jul 17, 2005; Voltes V: "Laser swooooooooord!"

My '01 F4i has been sitting for a few months after it started having trouble staying running while going fast down the freeway. Weather is turning and I'm tired of looking at it wasting away while I drive my beater to work.

What's wrong with my bike? This is from, gosh, six or so months ago so I'm going to describe the problems as best I can.

It initially began as problems catching when starting - a simple ignition push would die instantly. I had to rev it up to 8k or so for a couple of seconds to keep the ignition going and get it to idle. Replaced the stock battery and it helped for a couple of days but the problem returned, but it was ridable so I put it off.

Then it died on me while I was driving home on the freeway at 80 (or higher *cough*) mph. The engine flat out died while the electrics still worked (i.e. headlight, instrument panel etc). A fascinating experience in not panicking. Pulled over, got it to restart and I took surface streets home not going above 2nd. After that it was Car Time.

I've done regular oil changes, replaced the battery and chain but everything else is essentially stock. Around 27,000 miles on the bike. I've run it for a few minutes now and again and while sluggish to catch (from not being used often enough) it holds idle fine. Bit rich.

Possibilities? Fuel filter, fuel injector, spark plugs? Valves wouldn't be relevant?

Interestingly enough my brother had an 02 F4i that developed idle problems around this milage, he never could get it sorted out and just sold it hosed up.

# ¿ Feb 9, 2011 22:59

Ammanas: Jul 17, 2005; Voltes V: "Laser swooooooooord!"

Yeah more info please

# ¿ Feb 10, 2011 22:40

Ammanas: Jul 17, 2005; Voltes V: "Laser swooooooooord!"

Z3n posted:

Ok, there's 3 parts that make up a charging system.

First is your battery. Obvious, and simple. Check it, charge it, it should maintain a voltage of about 12.8v overnight. You can also get it tested at your local auto shop. The first step is ALWAYS to make sure your battery is good. I've seen batteries fail in very strange ways that play hell with charging system diagnosis. With the bike on, and running at 5k, you should see ~14v DC at the battery. If you do not, you have a problem with your charging system.

The next thing to check is the stator. It mounts to your engine casing, and creates AC current thanks to a large set of rotating magnets attached to the crank. You'll see 3 yellow wires coming off the left side engine cover, trace those up to a connector, and disconnect it.

Once you have the connector disconnected, inspect the wiring for any damaged connectors or burned/shorted wires. It should be pretty obvious, and look like something like this:

You need to check those 3 wires with the bike reved up to 5k and the multimeter set to AC Volts. Check them 1->2, 2->3, and 1->3. You should get a consistent 40-60v AC across the 3 sets of wires. Also, check from one of the wires to an unpainted part of the engine. If you get more than ~10-15v AC in bleed over, then your stator is grounding out, and needs to be replaced. If you're not getting 40-60v across all 3 wires, your stator has failed, and needs to be replaced.

If you're good on the stator, then it's time to move on to the regulator/rectifier. It converts the AC voltage from the stator to 14v DC for the battery to charge off of. If you're getting good AC power out of the stator but not 14v DC at the battery at 5k RPM, then either your R/R has failed or a connector or your wiring harness has burned up. To make it easy you can use a wiring harness diagram and your multimeter to make sure all of the wires are intact with minimal resistance. If the R/R has failed, there's no fixing it, it just needs to be replaced. I have seen connectors fail but the R/R still be functional, so hardwiring them together can be worth a shot there's been a failure at the connector but the R/R is still ok. If you can, temporarily hook things up with jumper leads so that you can test before you go hacking apart the stock wiring harness.

80% of the time these failures are R/R failures. 15% of the time it's a wiring failure, and the other 5% of the time it's a stator failure. Ocassionally you'll burn up the wiring harness when the R/R or stator fails, too, so check carefully. Wiring harness issues and charging problems are pretty simple but patience and being thorough is the key to fixing them right.

Good luck, post up if anything's unclear or you have any additional questions

Bumping this cuz I'm finally getting around to working on my bike.

Battery is fine, 14v when running. When I do the stator wiring checks against each other (i.e. 1-2, 1-3, 2-3) I get a pretty consistent read, around 57 volts.

But when I try the one wire against the frame test I get arouynd 16v - but I get this with just one end of the multimeter checking the output whether its against the frame or not. What's up?

The wiring itself looks alright but I'd need to take the tank off to get to the entire wiring unit.

# ¿ Apr 7, 2011 21:03

Ammanas: Jul 17, 2005; Voltes V: "Laser swooooooooord!"

Z3n posted:

14v DC when running and reved up to 5k? 16v AC from the stator to the engine ground is a fair bit of bleed over, but if you're still getting 14v DC at the battery when reved to 5k, then you're ok.

Have you checked the battery recently? What's the voltage on it fresh off the charger and after sitting? What does it drop to when you crank the bike over?

I took it off the trickle charger today after 2 days. It was dead, obviously from sitting nearly a year. I'll check the voltage off the battery when revved.

I'm amazed that the gas hasn't gone bad. I took it out and rode for about 20 minutes and it responded perfectly.

Keep in mind my problem (back then) was largely deteriorative, it got worse as time went by, supporting the idea that there's a charging system problem. Pretty amazed it flat out died while in motion though, that was stunning.

# ¿ Apr 7, 2011 23:14

Ammanas: Jul 17, 2005; Voltes V: "Laser swooooooooord!"

Z3n posted:

Ammanas,

I bet you're going to find that the voltage drops down as you rev the bike. 20 minutes of riding isn't enough time for the battery to completely drain. Probably need a new R/R.

Voltage stayed the same when revving the bike, around 14v.

# ¿ Apr 11, 2011 20:17

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# ¿ May 24, 2013 03:41

Ammanas: Jul 17, 2005; Voltes V: "Laser swooooooooord!"

What would make a fuel injected bike run rich?

# ¿ May 16, 2011 01:59

The Something Awful Forums > Discussion > Automotive Insanity > Cycle Asylum > Motorcycle Question Thread II: Less chatting and more questions