How & when should you cut/trim HT leads | GTAMotorcycle.com

How & when should you cut/trim HT leads

smudger

Well-known member
Still struggling with the bogging down of my 1991 ZX7 at high rpm (above 7500) even though carbs have been thoroughly cleaned & the (Dyno) jets re-set to factory spec for the OEM muffler.
Am now thinking ignition system, maybe too much load for it at high rpm????
Or perhaps the spark from 1 cylinder is not strong enough to cope with lots of fuel at higher rpm as someone following me at Cayuga yesterday commented that when the bike sounded to run rough at rpm's above 7500 they saw a puff or 2 of black smoke from the muffler?

  • What would prompt you to remove the plug caps & trim the HT lead & re-fit the caps?
  • How do you trim/cut the HT lead?
  • How do the leads come off the coil - pull off or screw off?

The bike has the 3 Ohm Dyno coils on it & I noticed that the rubber cap over the HT lead & top of the plug cap on cylinder #4 has some little splits in it, would that make a difference?
Smudger
 
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lot of questions...

trim HT leads if you want - or replace them since you seen they are cracked/split

i find it odd you have dyno jets with a stock exhaust system

YOUR QUESTION: how do the HT leads come off, pull off or screw? why dont you just look....

was bike previously running well?

RED FLAG: you had the carbs jets re-set? jets are replaced, not re-set. who did the work? was the bike running well previously? are the main jets OEM stock size

accelerating at 7500 rpm and up the bike will be "on the mains"

did you ever notice an improvement when you turned the throttle down a bit, rather than holding it wide open?
hve you looked at spark plugs for a hint?
 
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Thanks for replying Boyoboy
So cylinder 1 was definitely not firing, only had lukewarm manifold when 2, 3 & 4 were very hot.
Noticed that the plug cap was cracked all the way through & could see evidence of arcing inside the plug cap so made a new plug lead with new plug cap for cylinder #1, replaced the plug cap on #4 & put 4 new plugs in - bike worked flawlessy at GBM this past Friday.
No idea on the dynojets, they must have been in the carbs when I bought it last October, maybe it had aftermarket exhaust which the seller took off before selling the bike.
The coil leads just pull off ha ha
I'm just glad she;s running ok now :)
 

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