Building, racing, crashing race cars with the 750 Motor Club
It’s been a while since I posted here, for which there’s a complicated reason that won’t fit into this margin.
We’re working up now to the next race at Anglesey. As I write it’s warm and sunny outside; doubtless this presages a race weekend at Anglesey with horizontal rain. Having suffered hugely at Anglesey in the past I’m very wary about the weather there.
 Well, I’ve managed to do a couple of small things but hopefully over the next week I can manage to spend a good deal of time in the garage. We’ve not got too much on over the next week, probably mainly because we didn’t arrange too much because of Anthea’s operation; a couple of months ago it was hard to think about Christmas. Mind you, she’s much better now which is great. We’re starting to talk about the next racing season which puts the pressure on my to actually get on with getting the car sorted.One thing that needs doing for the new engine is the inlet. The CBR1000 engine has two sets of injectors. The primary ones are in the normal place on the throttle bodies; you can see them on the right of this photo of the airbox. There is another set though which are positioned above the inlet trumpets and squirt directly into the trumpet when the ECU decides that a huge dose of fuel would be useful. You can see the secondary injectors on the top of the airbox here. The problem with all this is, of course, that the standard airbox ends up with being really tall. This isn’t a problem on the bike but in a car it’s a pain. Most of the modern bike engines end up needing quite a bonnet bulge. Dan’s car has a positive skyscraper for example. However, Andy says he’s making a new GRP airbox which will be better, although it’s still going to be tall. |
 Not too much progress to report, but a bit anyway.
The major activity over the last couple of days has been converting this thing into somthing useful. This is the entire loom from the bike, other than the tails connected directly to the lights and so on. It’s a lot more complicated than the equivalent thing for the CBR900. It’s also made doubly difficult to use by being set up to connect properly to all the sensors, and so on, when in the bike. On the bike the ECU mounts on the very top of the airbox and the loom wraps around the engine to all the sensors and so on. The problem is that the top of the airbox would be a daft place to put the ECU in the car. If I mount it, as seems sensible, on the scuttle then nothing’s going to fit any more. |
Continue reading “The red one goes to the green one with the purply stripe”
 I seem to have been beavering, in a rather restrained way, away for ages and not getting that far. However, things are happening even though the on-track day is getting alarming closer and closer.
I said I’d probably have to modify the pedal box again, and I’ve now done this. As you can see from the photo I’ve cut off the top corner of the box. I have checked that my size 12 race boots don’t bash into the new corners. (And, for the reader who questioned me; yes, it was the left boot.) The other thing I’ve done is added a new master cylinder which you can also see in the photo. This isn’t actually the final cylinder but a spare one I had lying around. Well, to be fair I knew I had it somewhere but it only took me about 2 hours to find it. I needed it in there, though, as when I made the engine mounting I was going to have to arrange to miss the additional obstruction. |
 One of the things I need to do for the new engine is to get a fuel tank that’s suitable for the new engine. The most critical issue here is the fuel pump mounting. In order to make the Honda ECU happy it’s been found to be best to use the standard CBR1000 fuel pump. This is an in-tank device that pokes up into the bottom of the bike’s tank.
So, the idea is to make the same sort of thing work in the car. In order to do that I need to get this device in the bottom of a tank. It’s upside down here but it provides the proper mounting for the Honda fuel pump. |
 Well, at last it was time to press on with the CBR1000 fit. I went up to Andy’s last weekend to look at how it fitted in Rob Grant’s striker. It didn’t look too difficult although I already knew I was going to have to make some brand new engine mountings.
First thing, though, was to take the CBR900 engine out, as seen in the picture here. This should, I hope, be the last time I take this engine out. |
The last race of the RGB season is coming up so the car needs a bit of preparation.
Most important is the oil cooler. I took this off before Oulton as it became apparent that something was leaking from somewhere. However, the oil temperatures at Oulton were back to being alarmingly high (as in the output from the logger just on the right.) As you can see, the oil temperature was up to nearly 160°C before the end of the race.
I’ve carried on using Susprog3D on the suspension and it’s really rather interesting, or alarming depending on your point of view. All I’ve done with the suspension in the past is just calculated the roll centres and used that, along with a nifty spreadsheet, to calculate the roll stiffness distribution. That was fairly successful. However, the current investigation is producing all sorts of odd things.