ZX6R Track bike Project
Discussion
Jonjo91 said:
I thought i was there yesterday. Hit the ignition....fuel leaking from the fuel mixture screws, all 4 of them.
So carbs off again and I think the floats my be sticking, they have been ultrasonically cleaned and then sat for a few weeks in a box. Any less anyone can suggest a different fix?
I've got the same issue on a pair of Ducati carbs. I suspect that the float heights are off and the needle valves are not shutting off the fuel until it is above the level of the overflow.So carbs off again and I think the floats my be sticking, they have been ultrasonically cleaned and then sat for a few weeks in a box. Any less anyone can suggest a different fix?
Having a nightmare with the rear shock. I think the nitrogen has leaked out, the bolt to the external reservoir showed a very small bit of oil around the copper washer, I’ve tightened this up since and all has been fine in terms of no oil showing, but guessing all the nitrogen has gone.
Even with the preload adjuster almost all the way down I’m getting 30mm static sag and 80mm rider sag. I weigh 12 stone 10 so not the heaviest out there. With the shock fitted I seem to have lost 25mm off the seat height too which will come from all the static sag?
I sent the shock away to be rebuilt and have new spring fitted for my weight – can’t remember spring rate so have emailed to double check what was fitted.
Could this annoying issue be something as simple as no nitrogen?
Even with the preload adjuster almost all the way down I’m getting 30mm static sag and 80mm rider sag. I weigh 12 stone 10 so not the heaviest out there. With the shock fitted I seem to have lost 25mm off the seat height too which will come from all the static sag?
I sent the shock away to be rebuilt and have new spring fitted for my weight – can’t remember spring rate so have emailed to double check what was fitted.
Could this annoying issue be something as simple as no nitrogen?
No, the purpose of the nitrogen is purely to prevent the oil cavitating and foaming up. The amount of spring "rate" that the pressurised nitrogen adds is absolutely negligible compared to the spring itself and will have no measurable impact on sag.
It sounds like whoever refurbed the shock has fitted the wrong spring.
It sounds like whoever refurbed the shock has fitted the wrong spring.
Still learning about suspension. Gone back to who did the rebuild to ask spring rate supplied.
What rate,length etc should I be looking for my weight(12st10lbs without leathers) and bike? (1997 zx6r) this is the final piece of the rebuild so eager to get it right and get the bike out for a blast.
What rate,length etc should I be looking for my weight(12st10lbs without leathers) and bike? (1997 zx6r) this is the final piece of the rebuild so eager to get it right and get the bike out for a blast.
For a rider weight of 178lbs on a 1997 ZX-6R, the Racetech spring calculator says:
Stock Shock Spring Rate: 8.6 kg/mm (stock)
Street:
Recommended Shock Spring Rate: 8.838 kg/mm (use closest available)
Race:
Recommended Shock Spring Rate: 9.015 kg/mm (use closest available)
Looks like the standard spring isn't too far out anyway in this case.
Stock Shock Spring Rate: 8.6 kg/mm (stock)
Street:
Recommended Shock Spring Rate: 8.838 kg/mm (use closest available)
Race:
Recommended Shock Spring Rate: 9.015 kg/mm (use closest available)
Looks like the standard spring isn't too far out anyway in this case.
Mr2Mike said:
For a rider weight of 178lbs on a 1997 ZX-6R, the Racetech spring calculator says:
Stock Shock Spring Rate: 8.6 kg/mm (stock)
Street:
Recommended Shock Spring Rate: 8.838 kg/mm (use closest available)
Race:
Recommended Shock Spring Rate: 9.015 kg/mm (use closest available)
Looks like the standard spring isn't too far out anyway in this case.
Thanks very much, very useful. Stock Shock Spring Rate: 8.6 kg/mm (stock)
Street:
Recommended Shock Spring Rate: 8.838 kg/mm (use closest available)
Race:
Recommended Shock Spring Rate: 9.015 kg/mm (use closest available)
Looks like the standard spring isn't too far out anyway in this case.
Had a reply from the supplier
"A 65mn spring is good for a person weighing 11-12.5 stone,this is from
an OHLINS spec sheet.An 8.6kg/mm is for a 14 stone person."
I did said in my original email to the supplier I weighed 83kg (apparently I've lost a few lbs since then..must have more beer and pies) so the 65 spring is off anyway.
How accurate is that Racetech calculator? Even taking a pinch of salt with the figures, what I have is miles off.
I spent hours searching for Kawasaki official spec spring rate etc but led to nothing.
Waiting on suppliers reply now
"A 65mn spring is good for a person weighing 11-12.5 stone,this is from
an OHLINS spec sheet.An 8.6kg/mm is for a 14 stone person."
I did said in my original email to the supplier I weighed 83kg (apparently I've lost a few lbs since then..must have more beer and pies) so the 65 spring is off anyway.
How accurate is that Racetech calculator? Even taking a pinch of salt with the figures, what I have is miles off.
I spent hours searching for Kawasaki official spec spring rate etc but led to nothing.
Waiting on suppliers reply now
Jonjo91 said:
Had a reply from the supplier
"A 65mn spring is good for a person weighing 11-12.5 stone,this is from
an OHLINS spec sheet.An 8.6kg/mm is for a 14 stone person."
I did said in my original email to the supplier I weighed 83kg (apparently I've lost a few lbs since then..must have more beer and pies) so the 65 spring is off anyway.
How accurate is that Racetech calculator? Even taking a pinch of salt with the figures, what I have is miles off.
I spent hours searching for Kawasaki official spec spring rate etc but led to nothing.
Waiting on suppliers reply now
I used the Racetech calculator when I fitted a new shock to both my SV650 and my CBR900RR and it felt perfect on both, firm but not stupidly stiff. The stock spring rates on Japanese sports bikes are never targeted at riders weighing 14 stone IME."A 65mn spring is good for a person weighing 11-12.5 stone,this is from
an OHLINS spec sheet.An 8.6kg/mm is for a 14 stone person."
I did said in my original email to the supplier I weighed 83kg (apparently I've lost a few lbs since then..must have more beer and pies) so the 65 spring is off anyway.
How accurate is that Racetech calculator? Even taking a pinch of salt with the figures, what I have is miles off.
I spent hours searching for Kawasaki official spec spring rate etc but led to nothing.
Waiting on suppliers reply now
Even ignoring the Racetech calculator, since you have far too much sag even with the pre-load wound right up means the spring rate is too low, a fact which is beyond debate (though I'm assuming you have the original shock linkage on the bike). It's not inconceivable that the Ohlins catalopgue has a mistake in it, or that they are looking at the wrong model, or at fork springs etc.
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