View Full Version : Mechanical question

December 29th, 2004, 05:29 PM
Thanks to Andrew and Tim for making sure I was going to get home.

Last night we put a new battery in the F2, because I haven't been riding it enough and it was pretty well dead. I made it to the Goose with no problems. But upon leaving I made it about 10 feet out of the parking lot before it died. (Yes, it was ran for a few minutes and was at a good operating temp) It took many tries, but then it fired and stayed on for maybe 30 seconds before dying again. Then after another 5 minutes we got it running and I was able to ride it home. I stopped at the gas station by the house only added 1.8 gallons, so it wasn't low. It fired back up without problem and made it home.
This morning I fired it up and it ran for maybe a minute before dying. Then after maybe 10-20 tries it fired again. It stayed on for maybe 3 or 4 minutes while I went inside to put my gear on. I heard the idle drop and headed outside only to hear it dye yet again. This time when I tried to start it if I gave it gas it made a knocking sound? I gave up and drove the truck.

Could this be:
bad spark plugs?
old gas (it has been in the bike for a few months)?
Dirty Carb?

Also the bike turns over fine it just doesn't want to fire.

Any other suggestions on things to check?

Sorry for the novel, but figured it would help with the diagnostics. ;)

[ December 29, 2004, 17:30: Message edited by: Heather ]

Greg Sampson
December 29th, 2004, 05:40 PM
My first thought is that you've got bad gas, given the knocking... but it could also be a dirty sparkplug since that would also cause it to miss. But, I'm no expert.

December 29th, 2004, 05:41 PM
It could be any one of the following or it could be a combination of them. I'd look into it in this order.

1) Spark Plugs. Cheap fix. Change them if they are old.

2) Change your air filter (or clean it if it is a K&N)

3) Old gas and/or clogged jets/injectors. Run that gas out and fill up with new. Put in some carb cleaner but only proportionally enough for the amount of gas you are putting in. This did wonders for my DRZ that was having a similar problem.

4) Change your fuel filter if it is real old.

5) After this, it starts to get more difficult and expensive. Luckily it shouldn't get this far. At this point you probably have to start looking at whether you are having spark, fuel, or air problems. If it is spark, it may be old wires or the coil. If it is fuel then you may need to look at changing the filter, pump, or lines. It could also (doubtfully due to the symptoms) be a leaky carb/throttle body where you are losing vacuum.

December 29th, 2004, 05:42 PM
One more important thing! Get that battery on a Battery Tender ASAP! Running a battery down is very bad for it. If it is new, keep it in good shape by getting it charged right back up!

mike s
December 29th, 2004, 06:18 PM

In addition to the battery tender put a little Stabil in your gas tank and run it briefly if you think you may not ride the bike for a while.
It is very cheap insurance compared to tearing into a carb or injectors.
Although it really doesn't sound like a battery issue you are welcome to borrow my battery tender if you are worried about the battery too.

Loyed Hinkel
December 29th, 2004, 06:32 PM
Fire your mechanic!!!! tongue.gif :D

Greg Sampson
December 29th, 2004, 06:39 PM
Wouldn't draining the gas and adding new be cheaper (and easier) than new plugs? I'd start there. Also, did it run better or worse when warm? It could also be carbon on the plugs or some gunk in the carb. Get a can of carb cleaner while your at it and clean them out if new gas doesn't work.

Also, get your spark plugs from this website (http://www.sparkplugs.com) as they are much cheaper than the dealer. Cyclegear also carries plugs.

December 29th, 2004, 06:51 PM
I just put a brand new battery in before going to the Goose. I have a battery tender but thanks anyways.

The spark plugs probably need to changed anyways so I might as well go ahead and do that. I usually get them at Cycle gear for the 80, I always forget to order them online. How long does it take them to ship? We will probably be working on the bike Friday so I will just go buy some at Cycle Gear. (Dave I am coming to see you again. :D ) Guess we will drain the gas too. It's a nice full tank too. :( Think it would work in my truck? ;) lol

The bike ran fine on the way home, except it didn't seem as peppy. Not sure if it was just me, but when I got on the gas it didnt seem to pull as hard as usual. :confused:

December 29th, 2004, 06:54 PM
Originally posted by Loweed:

Fire your mechanic!!!! Don't think I can blame this one on him. He hasn't touched the F2 in a while. I think she is just feeling neglected. ;) I keep running off to the track without her. :(

December 29th, 2004, 06:59 PM
I just put a brand new battery in before going to the Goose. I have a battery tender but thanks anyways. It is always highly recommended to trickle charge a new battery overnight before it is put to use.

A weak battery can cause the regulator/rectifier to overheat. And since the Honda reg/rect already has bad reputation I'd closely scrutinize that component.

As for problem solving, I'd try new plugs and charging the battery. Then check the voltage of your charging system with the vehicle running. If it's not greater than 13.5 volts or more than 16 volts, you've a fried reg/rect.

December 29th, 2004, 07:00 PM
It is probably the gas and/or carbs. When it is cold, it is choked so it gets plenty of gas but as it warms up, it leans out to normal and it chokes. Drain the gas, put in carb cleaner, and you should be fine.

December 29th, 2004, 07:05 PM
We checked the Voltage after putting in the new battery and it was 14V, (we checked that to make sure it was the battery that was dead and not the reg/rect) I also have an added heat sink safety wired onto my reg/rect, not sure how much it helps, but it makes me feel better. ;)

December 29th, 2004, 07:08 PM
Guess I will start with the gas since it's easy enough.
Thanks for all the responses. I will let you know how it goes, but it may be Friday before I get to it. That way if we have to tear the carbs apart we will have time. ;)

December 29th, 2004, 07:15 PM
Intermittent electrical is a good suspect too especially as the batt was replaced, check for spark delivery when it refuses to start. You sure it's not a circlip floating around in there somewhere? :D

[ December 29, 2004, 19:19: Message edited by: Faisal Khan ]

December 29th, 2004, 07:19 PM

No, no circlips in there. ;)

The Big Spank Daddy
December 29th, 2004, 08:04 PM
Check your email, I sent you a message. I might have an answer, maybe.

December 30th, 2004, 09:55 AM
my f2 had a similar problems. It was the petcock. It is vacumn operated and the rubber diaphram was torn.

December 30th, 2004, 11:25 AM
Same exact thing happened to my CBR F2 when it sat a while.

I changed the gas, cleaned out the carbs, new plugs, and she ran like a champ again.

December 30th, 2004, 03:05 PM
Just another suggestion:

You must check the reg/rec while the engine is running... and BTW it can be out of spec either way (too little or too much voltage) in either case the battery can get fried.

Hondas are notorious for poor reg/rec's.

December 30th, 2004, 04:27 PM
Originally posted by CBeaR:
my f2 had a similar problems. It was the petcock. It is vacumn operated and the rubber diaphram was torn. Did the pet's **** tear the diaphram? :rolleyes:

December 30th, 2004, 04:38 PM
One cheap & quick check you can make is ride with a half full tank with the filler door open. If the symptoms go away, the vent hose is clogged. Although the symtoms of this fault is usually loss of power at highway speeds and not stalling at or near idle.

Loyed Hinkel
December 30th, 2004, 06:21 PM
I remember the last problem the bike had with the fuel tank. tongue.gif

Of course it may just have some mud in it. :D

YZF Cathy
December 30th, 2004, 09:03 PM
[/qb][/QUOTE]Did the pet's **** tear the diaphram? :rolleyes: [/QB][/QUOTE]

Sean, Sean, sean.............

December 30th, 2004, 09:36 PM
Yes, I remember the last problem with the fuel tank too. Cost me a full tank of gas. And had your pops not crashed the bike and taken the belly pan for repair it might have been a little toasty and I might of had to jump. ;)

December 30th, 2004, 09:43 PM
Going to work on it tomorrow. Thanks for all the ideas. Guess I will start with the easiest and go from there. Already bought plugs since I don't think we've ever changed them since I bought the bike.
How long are they good for? The two-smoke gets a new one every 2 or 3 races. But it only takes one and two-smokes run so much better with new plugs.

[ December 30, 2004, 21:45: Message edited by: Heather ]

December 31st, 2004, 08:19 AM
There is a simple diagnostic you can try to see if the tank is pulling a vacuum. Run the bike with the gas cap open. If it runs fine it, I'd check the vacuum lines and diaphram.

Brian Montgomery
January 1st, 2005, 10:58 AM
I would look at the 3 yellow wires that are in the plug for the rectifier. Norious Honda problem in old bikes. Chris sent the email. I am almost willing to bet 100% that it will be the solution to the problem. They Heat up over time, the contacts get dirty and melt. Sometimes they even get grounded out on the subframe. Like Mels did in Arkansas on the IBI. I fixed her up and I doubt she has had a problem since.

January 1st, 2005, 11:46 AM
We looked at those wires and they appear to be fine. We changed the sparkplugs. One was loose and had turned colers up higher than the rest. But after putting new ones in it still won't fire. It cranks no problem, but it won't fire at all anymore. Ever since the knocking sound it hasn't fired since? Ryan is cleaning the carbs right now. When he pulled them off the far right side of the carb had build up of some sort. But no idea where it came from.

January 1st, 2005, 11:48 AM
With the reg/rect problem would the bike crank fine?

January 1st, 2005, 01:31 PM

January 1st, 2005, 01:55 PM
If the residue in the float chambers is white it's probably due to condensation in the fuel. I suspect that the problem is fuel related. Cleaning the carbs and making sure the float valves are free should cure it.

Good luck.

January 1st, 2005, 03:35 PM
Check your fuel pump.

January 1st, 2005, 07:42 PM
fuel pump? F2's don't have those, but thanks. ;)

It's alive again though. After cleaning the carbs and putting new plugs in it still didn't start. But after messing with the wires for the kickstand kill switch it fired right up and ran for 30 minutes straight with no problem.

January 1st, 2005, 07:54 PM
[QUOTE]Originally posted by Heather:
[QB] fuel pump? F2's don't have those, but thanks. ;)

Ummmmm, yes it does have a fuel pump! Under left side cover I believe. Looks like a little black can with wires and fuel line coming out.

January 1st, 2005, 08:10 PM
No fuel pump on F2 only on F1 hurricaine and F3's

January 1st, 2005, 08:32 PM
Nope no fuel pump... ;)

Check bikebandit.com for a 1992 F2 if you want, but it's not there.
F3's have one though.

The Big Spank Daddy
January 2nd, 2005, 07:23 AM
**** interlock switches...guess that's why mine are all disconnected (defeated).

Loyed Hinkel
January 2nd, 2005, 08:38 PM

All that and it was a loose-ish kickstand switch?

tongue.gif tongue.gif tongue.gif tongue.gif tongue.gif tongue.gif

Do tell us which of you found the problem. smile.gif

January 3rd, 2005, 06:56 AM
Like Chris I defeated mine. I donít want any surprises while running down a bumpy road. Marginal switch, big bump, engine suddenly dies in turn, bad things happen.

The switch was put there by lawyers to prevent legal action from people who ride off with the side stand down. First left turn is interesting.

I figure is natural selection in action. Kinda like riding while standing on the seat.

January 3rd, 2005, 09:40 AM
Originally posted by sportbiker929:
Originally posted by Heather:
fuel pump? F2's don't have those, but thanks. ;)

Ummmmm, yes it does have a fuel pump! Under left side cover I believe. Looks like a little black can with wires and fuel line coming out. OH NO... someone must have stolen my fuel pump! tongue.gif

Its vacuum operated.. smile.gif

January 3rd, 2005, 08:52 PM
ok, so it doesn't have a fuel pump. I would have sworn it did. Oh well, so its not the fuel pump.