CZ 250 and 400 ignition timings

[Simo63]

Hey CZ gurus can you help me with ignition timing on my 2 1973/74 CZ's.

One is a 250 and one is a 400.  Both bikes have a PVL ignitions fitted and I'm just looking for the timing specs for these bikes.

Thanks

[Davey Crocket]

Are they in the RACQ for free towing when they break down?

[Simo63]

Are they in the RACQ for free towing when they break down?

LOL .. they don't have to be John .. I'm an ultracare member so whatever I'm driving or riding is covered 

Now do something useful and find me those timing specs I need will ya 

[tony27]

Don't know about timing for PVL ignition but the standard timing for the 250 is 2.8 - 3.0mm btd & for the 400 is 3.4 - 3.6mm, I ended up setting my 400 to 3.5mm at maximum advance on the hybrid Suzuki ignition

[Simo63]

Don't know about timing for PVL ignition but the standard timing for the 250 is 2.8 - 3.0mm btd & for the 400 is 3.4 - 3.6mm, I ended up setting my 400 to 3.5mm at maximum advance on the hybrid Suzuki ignition

Thanks Tony.  Would the PVL ignition change the timing?

[shortshifter]

I have specs for this,will bring on Wednesday.They would have been set up already wouldn't they?

[Simo63]

I have specs for this,will bring on Wednesday.They would have been set up already wouldn't they?

Thanks Paul. 

I imagine it would have been set up Paul but I was told the 400 would be "hugely powerful" and you could leave it in one gear and ride it because of the huge torque but that isn't the impression I got when racing it at Toowoomba recently.  It didn't seem like it was quick and it cetainly did not pull out of corners low in the revs like the tractor I was expecting 

I was talking to the guy that was my mechanic back when I was road racing about the lack of power and grunt (in my opinion) and the first thing he questioned was ignition timing.  Once we know that is right then we can look further.

On paper the bike sounds good, rebuilt engine, Mikuni Carb, PVL ignition, GMC pipe .. the list reads like an A-List of parts so on paper it should go good you would think.  I runs okay but it's just not as powerful as I expected and I wanted to ask so we can check it as it's his son that will be riding it at the Nats next week.

Maybe I should call Chris and ask him if the PVL's have different timing specs to the origninal points but I couldn't imagine that would be the case.

[shortshifter]

Yep,should be bags of torque.The hand drawn diagram I've got is from Mark at NW Maico and CZ,is for the 250.From memory the ignitions aren't actually PVL brand but something similar.Yeah maybe give Chris a call,this is a front running bike in the right hands.Are you being cyber stalked by Davey Crocket?

[Simo63]

Yep,should be bags of torque.The hand drawn diagram I've got is from Mark at NW Maico and CZ,is for the 250.From memory the ignitions aren't actually PVL brand but something similar.Yeah maybe give Chris a call,this is a front running bike in the right hands.Are you being cyber stalked by Davey Crocket?

Thanks Paul.  I thought Chris said they were PVL's?

I did achieve 2 second placings on it at Toowoomba once I figured out how to ride around the lack of torque but with the gearbox as "typical CZ" as it is, I would rather have it pull better and not have to play a tune on the gearlever to get it to perform.  It also didn't have the top end I had hoped so I suspect something isn't quite right.  Could be jetting as I didn't change the jets to compensate for the altitude.

Everything else on the bike is fine, handles nicely, stops well etc but just lacks mumbo in  my humble opinion.

I think Davey has a secret fetish for me .... I probably should stop sending him pics of me in fishnet tights

[shortshifter]

Simmo,Tony's figures are dead on,same as on my diagram.Send me your fax number and I'll send you a copy.

[Simo63]

Simmo,Tony's figures are dead on,same as on my diagram.Send me your fax number and I'll send you a copy.

Okay I sent you an SMS.  R u coming over tomorrow night?

Cheers mate.