Honda-SOHC

SOHC.co.uk Forums => CB500/550 => Topic started by: petermigreen on May 20, 2018, 09:47:00 PM

Title: Hard Starting
Post by: petermigreen on May 20, 2018, 09:47:00 PM

Weird one.
Put a brand new battery on my 500 and when I press starter button the engine cranks but really slow and sounds like flat battery but as stated battery brand new/fully charged and also tried with another battery which I know is good so I'm eliminating the battery.
Earthing is fine and also tried with jump wire from negative on battery to crankcase with same symptom.

Starts easy on the kick start so I'm eliminating mechanical resistance.
Starts easy on button when warmed up.


So what causes it to crank so slow/hard? starter motor? something I can't think of.

Thanks, Peter

Title: Re: Hard Starting
Post by: Trigger on May 20, 2018, 09:57:55 PM

You scratch my head and I will scratch yours. I have the same problem on a 750 at the moment. I have changed the battery, solenoid, new earth lead, good ground  ???

Title: Re: Hard Starting
Post by: hairygit on May 20, 2018, 10:28:52 PM

Starter tor brushes, replace (easy) clean commutator and undercut if necessary.

Title: Re: Hard Starting
Post by: mike the bike on May 20, 2018, 10:33:25 PM

Check the battery voltage and condition of the battery.  Does it start OK when using jump leads?
Check the chassis earthing point.  Is it a duff starter solenoid?  check by shorting across the two main terminals.  Is the starter motor itself sluggish?  What is the 12V connection like on the starter?What voltage are you getting on the starter? Are the starter brushes OK.
That'll keep you busy for an hour or so.

Title: Re: Hard Starting
Post by: SteveW on May 22, 2018, 08:12:16 AM

Check the starter cable itself from the starter to the solenoid.

I had the same problem, the starter cable was not routed properly.
Some previous owner must have had the starter off, when they refitted it, the cable was not through the rubber bush behind the sprocket cover.

The sprocket cover was then screwed on crushing the starter cable, cable shorts to the case and therefore to ground.

Starter turns slowly and I was getting whisps of smoke from the point at which the cable was pinched.

Title: Re: Hard Starting
Post by: petermigreen on June 27, 2018, 09:42:55 PM

Resolution to this one now that I've got round to it.
Changed the brushes even though they had lots of meat left on them and undercut and cleaned the commutator.
Spins up lovely now and works as it should.
Peter