Polarity reversed on 81 gs450

[Guest]

Hello everyone it seems a better may have been out on backwards on my 450 and now nothing works. I am able to get lights if I hook it up to a jump box so I think the battery is toast. I'm not able to get it to start with the starter button. Not even a click. One thing I was able to do was push start it with no battery and everything came to life but in 3rd gear with the throttle open it wouldn't rev at all or pick up speed. If I dropped a gear it would misfire terribly. Any advice I could get would be much appreciated. Thanks everyone!

[Steve]

First of all, welcome.

Next, remove the battery from the bike. Use a jump box or jumper cables to a vehicle that is NOT RUNNING, connect your battery cables to the jumper cables. See if the bike works.

Is this bike new to you or do you know some of the history? If you do know some of the history, how long has it been since it ran regularly? Last valve adjustment? Last oil change? Date code on the tires?

If the bike is not new to you, assume that NOTHING has been done, and you will have to do it all. Include a carb rebuild on the list of things to do.

Have a look in our library, paying particular attention to the Top 10 Newbie Mistakes.

.

[Adammworden]

First of all, welcome.

Next, remove the battery from the bike. Use a jump box or jumper cables to a vehicle that is NOT RUNNING, connect your battery cables to the jumper cables. See if the bike works.

Is this bike new to you or do you know some of the history? If you do know some of the history, how long has it been since it ran regularly? Last valve adjustment? Last oil change? Date code on the tires?

If the bike is not new to you, assume that NOTHING has been done, and you will have to do it all. Include a carb rebuild on the list of things to do.

Have a look in our library, paying particular attention to the Top 10 Newbie Mistakes.

.

i did try that and it did not start, wouldn't even click. Could this be a blown fuse or something worse? Is newish to me but it has been running fine for about a month carbs could use some cleaning and usually takes a bit to get going but normally they clear up quickly. I wonder if it's not spitting out because the rpms aren't getting high enough but I don't know what would stop it from getting any higher rpms. Thanks for the help in advance.

[Steve]

Check for a blown fuse. Not sure how many you have on that bike (what year is it?). If you have only one fuse and your lights work, the fuse must be OK. If you have more than one fuse, the lights and ignition are on different fuses.

Hard starting can happen for three reasons:
1. Dirty carbs and/or incorrect mixture settings
2. Improper valve clearances (usually tight)
3. Weak battery

When everything is working properly, you should be able to set the proper amount of "choke", turn the key ON, hold the clutch lever, then just give the starter button a stern look and the bike will be running.

.

[Adammworden]

That is the first thing I'll do tomorrow. I'm not sure how many are on t it was wired by a precious owner. It's an 81 gs450. I'm hoping it's just a blown fuse so I'll check in the morning and report back. As far as hard starting is that what it's called when the bike runs but doesn't gain any rpms with a full throttle? If I drop a gear it just misfires tho I was doing that without the battery in so maybe that was the issue. Carbs do need to be cleaned and re jetted which is next but I'm hoping it's not something worse since the battery was reversed for a bit. If it's not a fuse any other ideas I could look into? Thanks again I will check the fuse tomorrow!

[tom203]

"One thing I was able to do was push start it with no battery and everything came to life but in 3rd gear with the throttle open it wouldn't rev at all or "

don't run these things without a battery in and connected- the r/r (rectifier/regulator) needs one or the charging voltage can spike too high, doing unpleasant things to expensive parts. Hopefully your bike didn't rev up too high in your push start episode.

[Adammworden]

"One thing I was able to do was push start it with no battery and everything came to life but in 3rd gear with the throttle open it wouldn't rev at all or "

don't run these things without a battery in and connected- the r/r (rectifier/regulator) needs one or the charging voltage can spike too high, doing unpleasant things to expensive parts. Hopefully your bike didn't rev up too high in your push start episode.

Oh ****. Good to know I actually couldn't rev it high at all so hopefully that saves me. Thanks for the heads up

[BigD_83]

I'm confused by your opening (mobile phone auto-correct induced?) line:


Hello everyone it seems a better may have been out on backwards on my 450 and now nothing works.



Care to clear up what you intended to say?

[Adammworden]

I'm confused by your opening (mobile phone auto-correct induced?) line:


Hello everyone it seems a better may have been out on backwards on my 450 and now nothing works.



Care to clear up what you intended to say?

Yea sorry. Battery.

[Adammworden]

Hello,
Just an update, I replaced the fuse which was blown and now have lights. I do not have starter but if we jump the wires we can get it to turn over but not start. It seems like only one spark plug is firing as well now, any thoughts?

[Redman]

New bike to you?

Maybe some one can say if a 450 requires the clutch to be pulled in for the starter button to power the solenoid .... which could be the "not even a click".

If one spark plug is firing then most of the ignition system is good. (and your reverse polarity incident apparently did not fry your igniter).
Problem is related to the other plug.
Do you know that the spark plugcaps can go bad? THey are replaceable, and cost about $5 a piece, and can be found at most any mo'cykle shop, need not be a zuki dealer.
Spark plug cap Like this:

https://www.denniskirk.com/ngk/lb05ez-spark-plug-cap-lb05ez.p20372.prd/20372.sku

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[Redman]

From BassCliff BikeCliff site:

https://onedrive.live.com/?cid=2370B62DDF9F0C6B&id=2370B62DDF9F0C6B%211031&parId=2370B62DDF9F0C6B%211030&o=OneUp

Yep, has clutch swtich (called "starter disconnect switch" on schematic, lower left on these Clymer manual schematics).

[Steve]

Now that you have power, your starter "issue" might simply be that you need to pull the clutch lever to engage the electric starter.

That was Suzuki's idea of a "safety" switch to prevent dummies from starting the bike in gear.

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[Adammworden]

New bike to you?

Maybe some one can say if a 450 requires the clutch to be pulled in for the starter button to power the solenoid .... which could be the "not even a click".

If one spark plug is firing then most of the ignition system is good. (and your reverse polarity incident apparently did not fry your igniter).
Problem is related to the other plug.
Do you know that the spark plugcaps can go bad? THey are replaceable, and cost about $5 a piece, and can be found at most any mo'cykle shop, need not be a zuki dealer.
Spark plug cap Like this:

https://www.denniskirk.com/ngk/lb05ez-spark-plug-cap-lb05ez.p20372.prd/20372.sku

.

Thanks I will give it a shot. Just another question it seems like the plate that houses the cdi and igniter is showing hit when I tests it. Should this plate be grounded or should it be coming up hot? I also noticed that a black wire coming out of the igniter was attached to the top left corner of the plate and that was hot as well. Is this correct? Thanks for the help I'm going to try the clutch now.