CBR600FY - Problem

Hi Guys

Gota bit of an issue with my bike (CBR600FY) at the moment. The bike starts from cold with no problems(even with the lights on. However, if I thenride a few miles (3.6 miles this morning), stop the bike & switch off theengine, and after a few seconds try and start it again, the engine struggles toturn over, like the battery is flat even though it was charged last night.

Thestrange thing is that if I leave the bike for an hour or so, it will start asnormal. Anyone had this happen to them or got any ideas as to what’s going on?

Whatvoltages should I get from the rectifier if I throw a meter across the batteryterminals with the engine running, with the lights on and off?

Whatindicated voltage from the battery (when pressing the starter button) wouldshow is as being on the way out?

Anyuseful advice would be most welcome. Thanksin advance.

when it fails, do the lights dim? or appear dimmer than usual?

seems strange that it would be a battery issue that would rectify itself over time.

Check the bikes earth straps
You could have a poor earth

I remembered seeing someone enquire about a similar problem in MCN a while ago. I managed to find it while sifting through my digital copies.

I know it’s not the same bike and not the exact same problem but it does sound somewhat similar. See if any of the suggestions made in the answer could be applicable to you:

A similar issue to yours on MCN forums: https://forum.motorcyclenews.com/topic/80938/bandit-hot-staring-problems/7
(apologies for cross-posting, hope it’s not forbidden)

Have a look/ask on here http://www.bikersoracle.com/cbr600/forum/index.php

Pretty sure I’ve heard about a hot starting issue on there.

Scorchio covered regulator rectifier fault finding last week

The Triumph RAT forum is the place to go have a read here

Just noticed that if I apply either the front or rear brake with the lights switched off, the small position light in the headlight cluster lights up albeit about half power. Is this connected to the original problem? Does this indicate a reg/rec fault?

that sounds like a crossed connection. as in 2 wires touching that shouldn’t be.

Tells you how to check the battery and charging system http://www.yuasabatteries.com/faqs.php?action=1&id=30
Probably not definitive but a start.

Possible poor earth as someone already said.

Could be your brake lights are earthing through another circuit, i.e. the parking lights circuit.
And/or there’s a short from the brake lights to parking lights circuit.