Honda CBR 300 Forum banner

1 - 11 of 11 Posts

·
Registered
Joined
·
5 Posts
Discussion Starter #1
Hello,

This is a newish 2018 CBR300R ABS with 3000 miles. All the initial maintenance has been done.

Over the last few weeks when I get to a stop light, the idle gets rough as if it is missing. This problem has got progressively worse. The weird thing is that it is typically fine for the first few minutes of a ride. When the engine dies at a stop light and i restart, it fires back up and runs normal for a mile then I have the issue again at idle. Today the dash just turned off after my ride, before i turned the key off. Not sure if that is related.

I replaced the air filter, no issues there. Most the service dealers here cannot see the bike for a week or so. Any help is appreciated. I do not know much about these bikes. My best guess is their might be a physical connection issue with the spark plug or the electronic system that controls the firing.
Any thoughts and inputs would be appreciated.

Thanks,
Brian
 

·
Registered
Joined
·
228 Posts
I would start checking the battery and the charging system. The battery needs to be fully charged first, then load tested. You may need to take it to your dealer's service dept., or an automotive supply store to load test for a bad cell. In inexpensive 12voltage tester can verify the charging system, but it's a waste of time to check until the battery is verified good. I'll admit it's early for a bad battery, but this a good place to start.:nerd:
 

·
Registered
Joined
·
5 Posts
Discussion Starter #5
I will charge the battery and then have it load tested. How would the bike start right back up after dying if that is the issue?
 

·
Registered
Joined
·
228 Posts
I will charge the battery and then have it load tested. How would the bike start right back up after dying if that is the issue?
I can't give you a good answer. But you can't check the charging system without having verified the battery is fully charged, and does not have a bad cell. Your problems sounds electrical to me. And it's the only logical and economical starting point. IMO, anything self diagnosed beyond this is hit-or-miss. Without proper knowledge and equipment to plug into the ECU's diagnostic side, you may stumble upon the fix, but the learning curve could be steeper than you like.
 

·
Registered
Joined
·
391 Posts
I’m with airhead 83. It very easily could be nothing to do with the battery, but unless that is established as good, nothing else can be reliably diagnosed. Besides, I have had any number of motorcycle/automotive problems cured by fixing battery/ground/charging, even when there is no way they should have been related. Now that electronics rule the world, this is only more true.
 

·
Registered
Joined
·
5 Posts
Discussion Starter #8
Well I did get the batter out today. It appears that the negative terminal was not secured, the bolt was loose & threads were cross threaded. Furthermore the terminal was cracked where the nut turned into it. Hopefully that is my problem in its entirety.

Any suggestions on replacement batteries? Also, what is a good site to get replacement hardware?
 

·
Premium Member
Joined
·
5,282 Posts

·
Registered
Joined
·
228 Posts
Brian, I believe most batteries will come with new bolts and washers. If not, you can always hand carry the old ones to a local automotive store to match up. Hope a new battery cures your problems.
 
1 - 11 of 11 Posts
Top