KEEPING OUR COOL
Over the last couple of meetings we’ve suffered from high temperatures while racing the ZX-7R.
A hot pace on a hot day means a hot engine.
At Mallory Park our Ritchie was losing power after 3 to 4 laps because of it, and at Rockingham – where we tried a larger Fireblade rad with a high-pressure cap – it wasn’t running at it’s best either, it was still much too hot
.
The only difference with the Fireblade rad was that it took longer to get up to temperature, but didn’t really keep it any cooler than the standard Kawasaki rad when it was running out on the circuit. We ended up switching back the original ZX-7R one in the end.
Ritchie has been asking some guys in the US, who ran Muzzy bikes back in the day, and found out that their bikes either had double radiators or ran a double-pass type radiator that can be modified fairly easily from the standard road radiator.
This needs a skilled alloy welder and because of time constraints – although it’s a relatively simple job – it won’t be done for Anglesey.
We have also found out that the air can be managed much better by channelling it through the front of the fairing directly into the radiator. A special shroud can be made and fitted inside the front of the fairing, mounted to the front of the radiator. Once again, this takes time, so we decided to get creative and make our own to be ready for the next round.
First we cut a model from cardboard to fit inside the front of the fairing.
Then we used this as a template, to create the fibreglass air intake.
A bit rough round the edges, but it worked out fine.
All cleaned up and trimmed to fit.
Painted and fitted to the rad, ready for the fairing to go on.
Secured to the side of the radiator the air can’t by-pass the sides, and is forced through the radiator fins. It’s like creating an air-box for cooling underneath the front of the fairing.
In principle it should work, we’ll just have to wait and see.
Other work going on in the garage is building a spare engine out of pieces from previously broken, spare engines and leftover parts. Amazing that we’ve got enough bits and pieces to build another strong motor.
We’ve had an old cylinder head re-skimmed and refreshed with lapped in valves and new seals.
As well as having the head skimmed, we had the ‘recycled-liner’ cylinder bores honed by Roland and Aslsop; specialists in machining racing engines. Thanks to Wiseco, who have delivered our new piston kits, rings and gaskets, all we have to do is put it all together.
Shouldn’t take us long – we’ve had enough practice putting these engines together now.
Looking forward to running this one in too.
We’ll be sticking this engine into one of our road bikes probably – for a week or two – that should be fun going to work.
When the flat-slides are running right the ZX-7R is anything but flat.
Along with checking everything with our existing engine, and fine-tuning the flat-side carbs again, we’ve had a pretty busy old time of it.
If all goes well after the next round we’ll be treating the ZX-7R to a bodywork and paint refresh - it deserves it, after it's worked so hard to put Ritchie on the top step so many times this year
See you at Anglesey for some ‘Cool Runnings’, hopefully.
TEAM 71
