Head Gasket!! :0(

Well, it's been in the garage for ages due to being a poor nursing student, but I'm now looking at getting it fixed!

My beautiful ZX7R has been languishing with very little use, since just after I had it rejetted a year or so ago, as a MASSIVE flat spot appeared between 2,000 and 7,000rpm!!
I then noticed there was a small amount of 'mayonnaise' on the oil filler cap.

I'm just wondering if anyone had a good idea of how much I'll be looking at to get a new head gasket fitted?

I'm going insane not being able to ride and I will likely need to ride to Uni in the next coupleof weeks, as I'm on a different site, that's further away & with very little parking!

[timwilky]

If it hasn't been used for some time. I would be thinking condensation and not a leaky head gasket

Hmmm...
Hadn't thought of that!
Put two & two together with the dirty great flat spot (& lack of power!) and came up with the gasket...

Next question:

Does anyone have a compression tester they might be kind enough to lend me, please!?

firstly restore the jetting to factory standard,

drain all old fuel, refill with fresh fuel

warm up gently and change oil.

warm up properly and see if the missfire still remains,

if so, return getting to old jets and start from there.

welcome back btw

[Sid Squid]

A ZX7 with duff carburation? Well that's never, not never ever happened before, oh no. Check all hoses for leaks, and ensure the airbox isn't distorted and fits the carbs and intakes neatly. I'd also refit the standard jets etc, I doubt that's the problem if it was working OK with them fitted before, but the standard stuff is right and reliable, so just to rule out any jetting faults put them back.

As for your concern over the head gasket, well that's somewhat premature to say the least, for every one with a bit of goo on the oil filler cap caused by a blown gasket there's 10,000,000,000 engines, (at least - probably more), that have a little condensation and oil contamination.

And anyway, welcome back! We haven't seen you around here for aaaaagggeeesss Tim.

Cheers guys!
Unfortunately, I don't have the original jets.
I took it to a garage to get it done re-jetted and dyno'd and they rejetted accordingly, advising there was little point in a dynojet kit and that they had plenty of jets around if it needed any. Was charged the agreed amount and given a beautiful, smooth dyno graph and a nicely running bike.
By the time I rode it again (a few months down the line, due to one thing or another), it had the gaping great flat spot, where it just shuts down. If you pin the throttle, it stutters & judders more and feels like it wants to stop!
I don't know how any of the things mentioned could have just happened!?
Any way - I'll have a look at some point next week and see what I find!

I know I've been away for ages - the pressures of being a husband & father, along with being broke and starting my nursing diploma have taken their toll!!
Still looked in from time to time but was generally too busy to post, let alone ride!!

My other project is testament to this, being sat in the garage in almost exactly the same (sorry) state I bought it for months ago! This DOES need a new head gasket though - clearly evident from the small stream of oil escaping from the gap between the block & the head when you run it!!

Update here!