ZZR400 cold start clutch issues

[MaxCannon]

Recently picked up a ZZR400
It's in reasonable condition and was very cheap.

One strange issue is that cold starts are impossible unless I pull in the clutch.

I notice that when on the centre stand in neutral blipping the throttle when cold causes the rear wheel to spin, almost as if the bike is in gear.

Could the clutch be dragging in some way (perhaps thick cold oil ?) and having a similar effect as trying to start when in gear.

Starting from cold with the clutch in works a treat, just wondering if a change to thinner oil or a clutch adjustment is in order.

[breakaway]

What oil is it running? What is the status of the clutch springs?

Disclaimer: I have no clue

[MaxCannon]

Oils was just changed by the bike shop
I'd asked for a Semi synth but I don't know if thats what I got.
The invoice said mineral oil but doesn't specify the grade.

This issue wasn't there prior to the change but then again it's been a lot colder recently.

I'm wondering if it's normal for the back wheel to turn when in N on the centre stand.
Don't ever remember it happening on the GN.

[Squiggles]

I'm wondering if it's normal for the back wheel to turn when in N on the centre stand.
Don't ever remember it happening on the GN.

Yep, its normal for it to spin slowly

[MaxCannon]

Yep, its normal for it to spin slowly

Ah - righto then

[CookMySock]

take it back to the workshop and show them what its doing.

Are you starting it in gear ? My bike tows heavily starting in gear with the clutch in. This is hard on the starter.

DB

[xwhatsit]

Wheel will spin slowly in neutral, so that's OK. Is it just a simple case of it being one of those silly bikes with a clutch switch that won't let you start unless you pull it in?

[FROSTY:Me]

heavy oil cold nights. The oil goes like treacle and keeps the clutch sorta engaged when theres no load on.

[xwhatsit]

heavy oil cold nights. The oil goes like treacle and keeps the clutch sorta engaged when theres no load on.

But but but...

I might be really confused here, but should it matter if the bike's in neutral? I mean, the clutch is out anyway. So whether or not the clutch is dragging shouldn't enter into it, right?

I'd understand about clutch drag being a problem if you were trying to start it in-gear, with the clutch in, but we're starting it in neutral with the clutch out.

[MaxCannon]

No clutch safety switch as far as I can see and it's not in gear.
Hot starts aren't a problem

Was a bit worried that the clutch was poked as there is already a big shopping list
Tyres
Brakes
Rear Shock

[FROSTY:Me]

But but but...

I might be really confused here, but should it matter if the bike's in neutral? I mean, the clutch is out anyway. So whether or not the clutch is dragging shouldn't enter into it, right?

I'd understand about clutch drag being a problem if you were trying to start it in-gear, with the clutch in, but we're starting it in neutral with the clutch out.

I was simplifying it --In Neutral or in gear clutch pulled in--same sort of effect. its the oil that causes the drag.

[Max Preload]

Disengaging the clutch with the lever when the engine is cold so the bike will start is simply compensating for the oil viscosity which is causing considerable drag through the gearbox. However this shouldn't be an issue unless it's an extremely thick oil.

Exactly why won't it start cold without the clutch lever in? It won't wind over? Or does it wind over but just won't fire? There should be no appreciable difference between the winding speed of the starter with the clutch engaged or disengaged.

I'd be looking at the battery condition as a first port of call, not oil.

[xwhatsit]

Oh really? How interesting. I've put 20W50 in my bike (mostly an accident) and when it's been overnight in a stone-cold garage it does require a fair bit of kicking and coaxing to get started. Once its warmed up a bit it's normal. I'll try pulling the clutch in and see what happens

Cheers.

[MaxCannon]

Exactly why won't it start cold without the clutch lever in?

It just turns over then dies.
Nothing will make it go, choke or blipping the throttle it just stalls.
When you blip the throttle it makes an odd sound, can't really describe it.

I'm going to do some more testing over the weekend and see what happens with a cold start on the centre stand.

[Sketchy_Racer]

It's bad form to start a motorcycle in gear. Don't be lazy. Park with it in neutral, then start in neutral.

As mention cold oil is enough to create a fluid drag between the gears, clutch plates and moving parts inside your motor. Having it in gear putting that extra load on your starter motor is unnessary. Also if the motor is cold your going to put it in neutral to warm up for a bit anyway (right!) so why not put it in neutral when the motor is off. It's easier too!