This Saturday saw a number of activities come to fruition.
Firstly we finished the cooling system and fitted a new fan that I had bought off ebay. The new fan is a full half a kilo lighter than the old fan, and it’s easier to mount. The CBr1000rr has an ECU controlled fan which starts the fan up based on the engine coolant temperature so in theory you do not need a separate thermostatic switch. However the ECU exhibits some odd behavior. It starts the fan when the water temp reaches 105 deg c and shuts it down again at 99, which is a bit odd essentially it keeps the coolant temp between 99 and 105. It also starts the fan under heavy acceleration which I guess is sensible. however when I’m on the grid I want the engine warm (say 85 deg c) but not cooking at 100-105. It’s going to get thrashed and hot enough pretty soon so lets start with some capacity in the coolant circuit. To that end I wired in a parallel manual switch for use in assembly/on the grid or in post race cool down plus a dashboard warning light to let me know it is on. That way I can manually control the coolant temperature as I want, and the ECU will protect me should I forget. Other than that and a few leaks that needed nipping up when we ran the engine the cooling circuit is complete. It seems fine…. how it stands up under race conditions with the Rads in the side only time will tell.
The other thing we finished was the exhaust system. I was going to change the direction of the can to get the exhaust exiting out of the side of the car. I may still do this, but for now I just wanted to get it running, so refitted the exhaust in the “straight out the back” configuration it was in in last season. To do this I had to shorten some of the link pipes and weld the exit pipe on the Cat. .
The gap between the exhaust can and the cat is to allow the driveshaft to articulate through its full travel. Incidentally the radiator fan has the happy side effect of also cooling the exhaust system and can. We don’t just throw this thing together you know!
At the front of the car Duncan got on with working on his favorite material (wood- he’s a boat builder/chippy by training) and he’s virtually finished the front floor.
As you can see it is now much easier to get to the master cylinders and much easier to replace. I will be putting a foam filled crash box up the front though.
So will coolant,fuel and oil (5 litres for a full fill where the oil hoses and filter are empty) all filled we were ready for a restart of the lump. A few fuel pump off cranks until the new oil pressure gauge read about 9 psi and then we went for it. Uh Oh she doesn’t go! Perhaps we shoudl plug the ECU in 
(it had been unplugged a few weeks ago for some welding). Hmm still no suck,push, bang blow.
Ah… connect the cam sensor.. and Vrooom! Nothing like the smell of exhaust and hot oil to stimulate the old enthusiasm gland
Interestingly the Cam sensor doesn’t show a FI code when disconnected, but the engine fails to start…. that’s worth remembering in the paddock!.
The new oil pressure and temp guages work fine, Pressure is 25 with cold oil and elevated idle, but with oil a 50degs it drops to about 15. At 6000 rpm it hits the regulation 71psi right on the button … FAB
About now we had an odd occurrence, while trying to get the indicator lights for fan switch to work we had some really odd beaviour.
The DL1 stopped working, the fanswitch also controlled the oil pressure warning light and then engine wouldn’t shutdown…even when Duncan was waving the FI key at me. Weird.
A confluence of events meant that the ECU was receiving power from a short near the fan (5v) as it turned out because the DL1/dash fuse had blown but the “indicator fuse” that lights a light on itself when it blows was still passing 5v. The DL1 wasn’t getting enough power to run properly and when the fan switch was turned on it sinked enough current to stop the oil pressure light from working. All very odd.
Of most concern was that removing the red FI Key didn’t kill the engine. The ghost in the machine kept it running in self sustaining mode, not good for scrutineering and not safe. The Auxiliary terminal on the FI key breaks a circuit when the key is pulled. I had used this to replace the kill switch in the original honda loom and it had always previously worked fine. However, the Kill switch circuit basically powers down the engine stop relay, which in turn should power down the ECU, the fuel pumps, the injectors and the stick coils, which are all powered (through) a couple of other relays by the engine stop relay.
Now either it was the short, an odd current loop caused but the not quite blown fuse, a faulty relay or I’d screwed up the wiring elsewhere. But the engine stop relay remained energized even with the FIA switch out.. and the engine still ran.
I can’t have that again, but there are so many connections in the original circuit that I would have to tear apart half the loom to fix it , so I’ve changed the kill switch to basically break the power line to the stick coils, as close a possible to the coils on the engine loom itself. That way no other power supply can feed the coils by accident and no petrol engine can run without sparks. I’m also going to replace all those “tell tale” fuses. I want a fuse to be on or off. Blown or not Blown…. passing 5v with all its myriad of unpredictable results on a 12v system is just daft.
So fuse replaced, and kill function rewired I ran her again. even with the ECU, fuel pumps and everything else still live… now break just the kill circuit and she dies. Job done!
So overall a successful weekend, with only a small amount of time faffing around chasing wiring demons…. we’re pretty much onto bodywork now, to which end I’ve decided that this season’s colour is going to be Subaru World Rally Blue. Paint code Subaru 02C provided I can get it in 1 pack acrylic (I don’t fancy painting 2 pack)