MRC Forum- brought to you by www.morini-riders-club.com Member: g7AW3f

Was wondering if any one has come across this before.
The starter works fine on a cold engine, but once the engine is hot the starter motor spins but won't start the engine I.e won't turn the engine.
Electrical or mechanical?
Thanks in advance.

No answer for you, I'm afraid, but have a similar problem on my K2.
Starts fine when cold with Kickstart or starter motor. When hot will easily start with kickstart, but not with starter motor. Starter motor spins OK and turns engine over fast but it will not fire up, even though it produces a good spark at plug.
Same fault, or is the starter motor drive slipping on yours so that the engine is not revolving?

Sicxtyone wrote:Was wondering if any one has come across this before.
The starter works fine on a cold engine, but once the engine is hot the starter motor spins but won't start the engine I.e won't turn the engine.
Electrical or mechanical?
Thanks in advance.

I would have thought mechanical if the engine is not being turned over.

Hi Richard,
Thanks for the reply.
Im pretty certain the engine isn't turning but I will have to check this.
On mine the kickstart is unusable as the previous owner fitted a non folding footrest so am dependant on the electric foot until I look into altering the foot peg

The engine will have it's clearances reduced when hot - no gas leakage past the piston rings, valves tighter etc, so if you have worn linings on the starter shoes they will slip. The old remedy was to use an automatic centre punch to punch dimples in the steel ring attached to the flywheel which worked put had a tendency to wear the friction material out even quicker. I would suggest you have the friction material replaced. This topic has already been discussed sometime last year. I have 507 barrels on a five hundred bottom end and 12 ;1 compression and have no problem with the clutch biting into the flywheel ring. It turns over easier when cold and is quite free running but when hot, it still bites but turns the engine more slowly before starting but it does start instantly. All my Morinis had the kick starter levers removed as has this one. If I want to kick start my bike, I will buy another MZ.

Thank you Mr HM,
This will be a good place to start investigations.

With a hot engine, try taking the footrest off and using the kickstart. Mine starts instantly that way, would be interested to hear if yours does the same!

Had a few hours this weekend to look into my starter issues.
Firstly the friction material is shot getting on for a third of each shoe is missing
So they will be sent to Villiers services for a re-line.
The brushes look fairly newish but there was a lot of dirt/ oily residue in there.
The previous owner said the starter had been refurbished ho hum
Also no rubber bung in the gearbox filler hole so if there was any oil in there it ain’t now practically empty.
While I’m here the handbook is a bit vague on adjusting the chain to the starter there only seems a tiny amount of adjustment available so a new chain looks needed
And Richard the bike starts fine on a hot engine if you have a big enough boot
Thanks Mr Webber.

I spent a lot of time getting my starter to work on my 350,including new chain,old one was shot and was almost touching the case,new starter clutch,cleaned out internals,new bronze gear,new oil seals new brush holder and brushes.I am currently(ha ha) using an Odyssey battery which being at least 12 Years old may be past its best. I know I am.And do you know what,the starter sometimes works really well. I intend to replace that Odyssey with an equivalent from BBL batteries, as this is as good but 30% cheaper and slightly less tall. john

I have a Motobatt in my K2 and it turns the starter very rapidly. I had one in a BMW F650 before that and it turned that lump easily, too. Price seems reasonable.

Continuing the subject, my 500 came with a motobatt 18 ah that stays on an Optimate. So it spins up well, however I have started to take apart the starter motor as the gearbox oil drains out as soon as you put it in. O ring seal behind sprocket.
So I intend to re new seals and bearings. 3potjohn could I ask where you sourced parts when you did your re build? Prob nlm. Do you have a parts list? Andrew at Mdina although always helpful drew a blank here.
Probably have to take to bits measure and look at bearing station or simply bearings.
The starter shoes are away at the moment with Villiiers services £33 seems ok as new set is north of £80.
A question about the chain I have got a new one to go in but comparing to the old it doesn't seem any better. The slotted adjustment is very small, should the chain have 2/3 mm slack? If so I'm struggling to get this.
Regards all