FZRSupport: the FZROnline Archive

Does anyone have any experience in replacing HT leads on an FZR600? My 1989 model is having some issues with a weak spark and one of the HT leads is 'leaking' it's spark when the bike is idling. I've seen the spark jumping onto the cylinder head, and it makes a 'clicking' noise whilst doing this.

I know that the HT leads are connected permanently to the coil packs on the bike. As far as I'm aware, my coil packs are all working well.

So I bought these new HT leads: http://www.ebay.co.uk/itm/361332299152? ... EBIDX%3AIT

My aim is to cut the old HT leads close to the coil packs and then use some HT lead connectors to attach the new HT leads. Any idea if this will work? Or is it best to just buy new coil packs?

Your plan will work Chris.

I am sure I replaced leads on those coils by cutting them as close to the coil as poss. then removing the remains with a
burr on a mutitool.
This exposed a spike inside the coil and I fitted the new leads over the spike and sealed with silicon.

The HT lead connectors are quite bulky...make sure you have room for 4 of them ...there's not a lot of spare space under there.

Those Dynapac leads are very dear to cut up...you went a bit over the top there...

Thanks for the response. And yes, I think I may have gone overboard with the HT leads! I couldn't figure out where to get any cheaper ones from.

Cheers. I'll give it a go and see if it all works.

Chris...you should still be able to get high quality HT lead on a reel from old school auto supply shops.
They would just cut off your total length and charge per ft/metre.
Caps...NGK doe a replacement that is nearly identical to stock.

All sorted now. Thanks for the replies guys.

I basically chopped the original leads right back to near the coil packs, then attached some HT lead connectors and then attached the new HT leads. Everything works perfectly.

Now I've got to sort out the issue of why my bike runs fine for about 500miles and then the spark plugs become very black (cylinder no.1 in particular) and then the bike starts to run on 3 cylinders. Once I clean the plugs then the bike performs perfectly again. I think it may be burning oil

More likely to be over rich mixture Chris...fuel levels firstly then emulsion tubes for ovality .
These aren't usually oil burners and if enough to foul a plug it is caked on baked deposits that are easily recognised.
The plug would need to be very oily not to spark...black and dry is excess fuel...then wet and misfiring is fouled.
Excess fuel forms a varnish that the spark cannot earth through.

Thanks for that. I'll have to check the feeling and mixture. Is it easy to do? I'll have to dig out a 'how to' from the forum.

The reason why I think the bike is burning oil is that the oil level does slowly go down over time. And there isn't any leaks to be seen.

Here's what the plugs looked like, as I've just pulled them out and cleaned them. Apologies for the lack of focus on the photos!

Cylinder 1: Wet, shiny and black


Cylinder 2: Dry and black. Not shiny


Cylinder 3: Slightly wet, shiny and black


Cylinder 4: Dry and black. Not shiny

Also check the choke plungers are returning fully.

That doesn't look like oil deposits
Fzr engines do use oil ..but not to the extent of oil fouling plugs. Mineral oil tends to burn less than semi.

Excellent. Cheers. The bike is due for an oil and filter change so I'll get some mineral oil for it.

Thanks for the advice on the choke plungers too. Any links on how to check them?

Operate the choke and feel if, when closed, they can be manually closed further.
I would also use new plugs for diagnosis...the ones in your pic look done for. They have been fouled/cleaned numerous times despite the electrode being relatively unworn.

Cheers for that. I'll check the choke and definitely need to buy new plugs.

Thanks again.