Nova Diff and CBR1000 Billet Sump

I've collected my loan differential and swinging sump from Nova engineering so I thought I'd post a couple of pictures. The differential has been a bit of a TV star before when it was used on in the Discovery series "Kit Car Crisis" where a guy was building a car to come and race ion RGB.

Unfortunately the series didn't show Kit car building in a very good light and mainly served to highlight some of the pitfalls that can befall an inexperienced car builder who is badlya advised . Me, I doubt I could go racing without the vast store of knowledge and experience that my mates in Cam7 and the RGB racing fraternity happily share with me.

However none of that is relevant to the Diff.

The main reasons for changing over from the existing diff are

The new diff offers an engine driven reverse. This removes an area of constant irritation because every time you adjust the gear ratios on my existing diff (by changing the drive sprockets) you have to move the diff to retension the chain and then you have to spend a good 30 minutes readjusting the electric reverse system. This discourages me from making changes in the paddock as I know it just takes ages and I'm usually stuck for time. Plus I've been known to forget and an inoperable reverse is a common reason for RGB cars to get excluded (disqualified). Plus after a couple of seasons racing one of the key lessions I've learned is to keep it simple stupid! Any thing that requires unnecessary precise adjustment, or simply adds to your workload in the paddock is bad. You're there to race!.. Everything else is a distraction and the more of those mechanical distractions you can remove the better.

1. The engine driven reverse actually has a chance of moving me backwards... unlike the current electric system.
2. The current electric system which also has an alarming habit of blowing batteries by over discharging them (I've already damaged 3 like this). This means that I can probably lose some weight by going for a smaller battery too.
3. The drive ratios are very easily changed by simply removing the blue aluminium mounting ring and bolting on a new driven sprocket (which also hides a cush drive to help reduce driveline shunt). In fact by changing both the front and rear sprockets you can get a very fine range of diff ratio adjustments although I think this would more faffing around than it's worth. Currently I can't change the driven sprocket as it is encased in enough steel to make the Forth road bridge extension so I can only change the front sprocket which is a bit of a pain and also only give quite coarse adjustment, plus my current diff's chainwheel needs replacing and some of the mounting bolts have a habit of coming lose.
4. It runs entirely enclosed so hopefully won't spray grease all over the engine bay like my current setup.
5. It weighs a bit less than my current setup (about 3 Kg), so I get these advanteges for no weight penalty. Although as it's a prototype unit no doubt at some stage I will pay a penalty of some sort as we hit teeting troubles. However Graham at Nova will hapily machine up some bespoke mounting brackets for me so quid pro quo. Grahams long term plan is to be able to use it as a stressed member, and hopefully over time we can reduce the weight even further.

While at Nova I also collected the billet sump pan, at this stage it is without the oil pickup so I can only dry assemble the engine, but that's ok as my current primary requirement for the sump is that it has a flat bottom. This is because tomorrow after a hefty bit of garage tidying I intend to start fitting the engine and the new diff. And having an engine that will simply sit flat on its bottom while I line it up and make the engine mounting frame around it will be a great advantage. The standard sump is pyramidal and the engine wants to do nothing but fall over at the moment.

The sump is very nicely machined from a large chunk of billet, but again it is a prototype unit.

After handling it, and looking at it for a few minutes two or three potential enhancements come to mind.

1. It needs a small drilling so that you can lockwire the sump plug in place
2. It need a fitting for an oil temp sender
3. it needs an extra mounting eye in the appropriate place so that the oil filter can be lock tied to it. Oil filters tend to unscrew themselves on bike engines if not held in place with a suitable jubilee clip or tie wrap and I know at least one engine that has been blown like this.
4. It could do with some cooling fins machining into the surfaces.

Hoiking out the ZX12- R + Chassis Weights

I've spent the day stripping and weighing the car I wanted some solid metrics against which I can measure the changes I plan to make to the car this winter.

Remember, I'm taking the slightly odd decision to have less power in my racer, as this will allow me to step down a class, and hopefully lose a lot of weight from the car which in turn will make me more competative in Class B.

So having borrowed Steve's corner weight scales I set about taking a bunch of measurements to get a solid idea of weights of each major component. What followed was quite enlightening, well it certainly explains why the marshalls grunt a bit when pushing me around the paddock.

Firstly I weighed the car as it came back from the Birkett, fully fuelled and full of oil and coolant without driver

It weighed 555.4Kg, Gosh that's quite a lot given that Tim's Fury is 470KG in the same condition and our class weightlimits are 560 and 530Kgs respectively, although that is normally at the end of the race when we are not carrying much fuel. Still it's pretty lardy!

Secondly I weighed the car with the driver in it. And ... well you don't really want to know! But I think there's a couple of bags of spuds hidden in the car somewhere or a fragment of neutron star! Let just say that I can easily miss the weight limit by 100KG it's the rowing machine for me this winter I think.

Next I drained all the fluids, oil, water and the 25+ litres of fuel, the weight without the driver but dry with all fluids drained was 531.2Kg. So that is some 24Kg of fluids most of which was fuel. But there is probably 8 KG of oil and water in the car.

Next I removed the ZX12R, and the engine lump complete with the exhuast headers and dry sump pump, it comes in at 90Kg. Given that it puts out over 180bhp that's 2BHP per kilo, a quite impressive power to weight ratio.

With the ZX12R, diff, exhuast and Drysump tank removed the car weighs 378.4KG, so the engine, diff and lub system and mounting hardware weighs 152Kgs.

Which actually gives me a bit of of hope, as the cbr1000rr is reputed to be about 65kg, add the diff at 27kg and say 10KG for exhaust and mounting hardware and I could be looking at a saving of around 50KG on the dryweight on the car + whatever I can off load from the lard arse in the drivers seat. That's got to be a reasonable goal for the winter, to offset the slight drop in power that the new engine will have.

Incidentally the Diff weighs in at 26.8 Kg without the CV joint cups, the Nova diff I'll be using weighs about 27 dead including the cups so allowing for the mounting hardware there is probably a couple of kilos to be saved by making the effort to get it into this chassis. I wasn't going to do this as it generates a bunch of other issues, like a different handbrake assembly and changing the driveshafts so on. But with a small weight saving to be made it must be a good idea. Also after a day dissassembling the engine bay the one thing I can accurately say is that is is absolutely full of lithium CV\Diff grease. It is absolutely everywhere and yucky as hell.

Swapping to the Nova diff is worth it just to keep the engine bay clean, but the other advantages of engine driven reverse, weight saving and so on make it a no brainer.

Such Fun at The Birkett

Team Genesis came 8th on the road in the Birkett!

There are a bunch of Photos at Isadora Poggis' site which far better explain the concept of the Birkett than any prose I can write here. It is a unique event in uk motoracing and if you ever get a chance to compete or watch it I heartily recommend that you go along. Just remember when you are looking at the pictures that all those teams were on the track at the same time and that we were all racing each other.

I'll certainly race in it again whenever I get a chance it was so much fun!

I'm 47D and a couple of specific pictures of me are at these links.
http://www.isadorapoggi.co.uk/2006/750/birkett/061028_184.htm
http://www.isadorapoggi.co.uk/2006/750/birkett/061028_234.htm


In short I had a the most fun exhilerating, entertaining and educational days racing I have ever completed. It was an absolute hoot!

I Learnt more about race craft and overtaking in one afternoon than I had accumulated in three entire seasons racing.

We turned up the day before with the express intention of getting the car scrutineered when there wasn't much of a crowd. Good job we did too, a faulty memory cell on my part meant I forgot to put the extinguisher control box in the car and a faulty earth connection meant I had no brake lights. so for the first time ever I failed scrutineering. All told it only took 15 mins to sort out but I wouldn't have wanted to do it on the morning of the race when 200 other cars were trying to get through scrutineering as well. On Friday afternoon it was quiet and we got our ticket to ride nice and quckly at the second visit.

The only other thing of note on Friday was the fact that the race van got us to the circuit with no problems whatsoever. The recent investements in new starter motor, alternator and switched to control the fridge are finally paying dividends.

Saturday

In the qualifying session I went out early and did 10 laps or so. It has been a couple of months since I raced and I wanted to get used to the relativly high speed differentials between the cars and evaluate the recent addition of the Gurney Strip to the back of the car. I'm happy to report it has made a big difference, the back end is now much less lively, in fact it is pretty planted to the track and when she does start to spin it is not an unrecoverable Snap SPin, more a gentle slide out of the backend which is nicely controllable on the throttle. All of this new stability was now reflected in very much improved grip. Previously I had been lifting slightly through the Woodcote kink in the main straight as the imbalance between front and rear end grip at this point made the car unstable and it felt like it was going to let go. With the new gurney flap it's just so planted and I can now hammer down the straight flat out all the way along. And of course improved stability and confidence meant faster times and I could do 1:11s without really trying very hard.

Remember I was also trying to learn how to overtake a Porche Carrera who was braking some 100m before I needed too, while trying to avoid a 2CV at the corner's apex which was plainly doing what seemed to be 35mph. Eventually I got brave enough to show the slower cars in fro ont my nose on the inside lines as we approached the corner so that they would know I was there. Then stuff it up the inside under braking and use the new found stability and grip to get round the bend.

The other guys in the Team, Tim Pell, Doug Carter and Steve Robinson all had pretty sucessful qualifying sessions, however Steve came in trailing oil from a failed union which caused us some concern.


The Race
Timp went out first and we started from a position of 10th on the Grid. Once underway it became pretty obvious that the pace had picked up substantially from practice. Tim moved up to 4th place and was plainly driving the wheels off his car fighting with the big block cobra in front and lapping in the 1:03s which was pretty something considering the mixed traffic they encountereed as they started to lap the rest of the field at about lap 4 or 5. Tim went on to set the fastest time of the day at 1:02:xx a top effort.

Tim came in and Doug went out and continued in much the same vein. Then it was Steve's turn, and as I was due out after Steve it was my job to be in the car, ready, helmeted and strapped in. Rady to go at a moment's notice in case he had a problem. A position some call "the hare" but I prefer the term "ready 5".

Unfortunately we lost Steve Robinson's car early in his session due to a thrown rod and blown engine, so I went out immediately and started mixing it with the different cars on the track. In this session I did 1:11s and 12s and came in some 25 laps later comepletely exhilerated I had been a bit trepidatious at the increased speed and the difficulty of negiotiating traffic. But I had such fun! Hammering along the back straight trying to find a way past three or four tin tops, all fighting amongst themselves for position and swapping lines across the track was really something. Of course it was easier now my car is a bit more planted and amongst the fastest out there but even so it was a hoot. I got overtaken by a few of the faster cars but generally I felt I had performed to my handicap marker lap.

The driving standards were exceptional, civilised & gentlemanly infact. By the end of the day I took to showing the cars in front my nose in their mirrors so that they knew I was chasing up the inside on the run in to Brooklands I had no one turn in on me all day,Ok some only gave a cars width plus an inch but that was all I now needed.

I went around Luffield up the inside of a Stock hatch and I felt I could have reached out and adjusted his wing mirror if he had needed me too. I touched Nobody all day. Top top fun.

With one car out and only three running the rest of the day was very busy with less than 30 mins between getting out of the car after your session and getting back in to be ready 5 for the next guy

I calculate I did 87 laps, 75+ of which were under race conditions, and I was mixing it with such different machinery everything from Toyata MR2s to classic Jag e types. And I got progressively much faster and more agressive during the day, and as a result I got overtaken less and less.

The Highlights were

• Outbraking a Westie and a tin top on the inside line at high speed into Copse , Holding it on the tighter line and then making it stick on the run up to MAggots.
• Outbraking loads of cars all day in the run in to Brooklands\Luffied.
• Stuffing it up the inside of a tin top a Luffied.
• Driving around the outside of Judy at Becketts.
• A couple of four or five lap battles with big engined Morgans and an Original Whale tail Jag.

The car was glued to the track all day, the Gurney flap has really helped it's stability and I was driving the wheels of it by the end... not wanting my sessions to end.

Now I can just play around with it at the limit... a bit more throttle here for controllable back end slide or to turn the nose in, bit less throttle there to get it to tuck in. I'd heard guys talk about playing about on the limit before but I've never been able to do. I guess parallel development of b oth car and driver is the key.:-)

It was such fun and my confidence grew hugely throughout the day.
This was refelcted in my laptimes... 1:11s in fist sessions, 1:9s in the second.
Best in my 3rd sessions was 1:06.87 ONE OH SIXES! Whooo Hooo! That is 3 seconds better than my previous best.

That would put me 10th ot 11th on the last RGB grid at Sillystone a move forward of 15 places from my last position. Bejezzus and that was on old rubber too!

Today I feel I really came of age as a driver, helped in no short part by a solid stable predictable platform to drive. Hopefully higher speeds and mixed traffic will no longer phase me.

We finished 8th of 51 teams on the road which is a fine effort, but the handicap system hurt us as did the loss of one of our faster drivers so we finished 5th in class. but it was none the less a top top day.

I've been wearing a very big grin for two days as a result

New Chassis Pics

I've scanned in a couple of pics of the new chassis. They are fairly poor quality I'm afraid as the paper copies roamed around in my trouser pockets for a while. However you can clearly see the construction method for the new chassis.

Final Preparation for the Birkett

Today I did my pre race checks for next weekends 6 hour relay race at Silverstone. For those of you not familiar with the Holly Birkett relay it is basically a 6 hour endurance race for teams of 4 or more drivers. It runs just like the the Le MAn race in that it starts at 11am finishes at 5pm exactly and whoever does the most laps wins!

Unlike Le Man though it is open to any sort of closed wheel cars, RGB cars, Jag XK120s, Caterhams and everything in between even the little reliant powered Formula 750 cars. With such a wide range of hardware they can't all be in one class and the race is handicapped.

Basically the team of fastest cars are the scratch team, in that they get no gredit laps. All other teams get a certain number of credit laps. The credited amount equals the difference in no of laps they will do and the number the scratch team will do on the six hour period. So if you do more than your assessed handicap amount you can win the overall handicap trophy even if you don't win on the road.

All very complicated but should be great fun... if a little busy with up to 50 cars on the track at once. I'm racing with Tim Pell, Steve Robinson and Doug Carter in a Team which will bring all 4 of the racing Genesii together in a single team and expect to do a couple of 30 minute sessions in the 6 hours.

The other guys think we might actually win (not normally a word in my racing vocabulary) as there are only one or two other teams with faster average lap times than the RGB cars. However as the slowest member of the team if this looks like becomeing a reality I'll happily let the faster boys drive extra laps

So today I did my normal pre race checks, on things like fuel, water, oil systems, suspension and so on. It usually takes all day to do this and today was no differerent. Infact I was slowed down a bit by the need to change a worn suspension bush on the right rear wishbone. Anther issue is that my front right tyre is pretty worn, (this one takes all the load on our clockwise mostly right hand turn circuits). I'm not going to buy new rubber at this end of the season (it degrades over the winter) so I swapped it with the front left. This reverses the tread pattern, but the Yokohama website says that the tyres are reversable and I know several people in the paddock that run them this way around so it shouldnt be any sort of problem.

I've a couple of little jobs to do during the week and then I'm ready. These are fit a new rear view mirror and hoover it out.

I also went around the car and labelled everything up so that the Team Genesis pit crew who will probably be unfamilier with my car know the tyre pressures to set, correct coolant level and so on.

Lastly I finalised the installation of an oil pressure guage and voltmeter in the race van. So that I can watch these variables.

Details of the Birket are on the 750 Motor Club Website at www.750MC.co.uk, it a great day out and well worth the 14 quid entrance fee.

It is held next Saturday October 28th 2006 at Silverstone

Next Year's Engine Arrives

Today my nice shiny new CBR1000 RR engine turned up from Malc at Yorkshire engines. Very new looking it is too. It looks like an American spec engine as it seems to be fitted with the standard American emissions control systems.

Along with it also arrived the CBR 10000 clocks which contain a very nice sweep tacho, and I’l be finding a way to incorporate this into the racer instead of the Digidash.

The CBR engine has a couple of other interesting quirks, firstly it does not have a gear position switch. Now the Kwaka zx12r has a gear position switch to tell the ECU which gear the system is in, so that the fuel and ignition mapping can adjusted accordingly. Usually the ECUs do things like limit the pickup in first so that the rider doesn’t fall of the back of the bike, provide max torque in the mid gears and them apply a top speed limit in 6th. Some racers have benefited from telling the system that it is always in 5th so that max power is always available without an ECU imposed limiter.

The lack of gear position switch must mean that the Honda ECU calculates gear ratio based on engine RPM vs output shaft speed using the gear ratios of the standard bike to modify the fuelling. The second issue is that I’ll be without a gear indicator in the racer as my current indicator is driven from the KWakas gearbox switch. Still it’ll save the weight of the wiring but will be a new challenge to have additional awareness of how many change downs are needed for each corner.

It also has a secondary set of external injector (injectors that are positioned above the inlet trumpets on the outside of the butterflies) which are housed and mounted in the airbox. Now this probably means that I’m going to have to retain the original airbox, which has a nifty little vacuum driven sealing flap on the air intake which is vacuum driven and closes when the engine is on overrun to ensure any fuel floating around inside the airbox gets sucked into the engine. I’m understandably nervous about fuel vapour in the engine bay. This will cause me some initial packaging issues as the air intake on the bike points forward in front of the engine. In the racer this will be facing the bulkhead so not to much air flowing there then!


On the subject of the digidash, I’m really only using this for oil and water pressure\temp alarms now, and for sporadic Laptiming. But I’ve never been very successful at getting the timing to work reliably and it’s a pretty heavy unit to just feed me Alarm data. Although in fairness I am also using the output from the sensors to feed into the DL1 Data logger.

SO my Plan is to lose the Digidash and replace it either with Tim Hoverd’s palm pilot based dash\laptimer which he wrote the code for. It does lap timing and sensor monitoring based on the serial stream out put from the DL1 and also does useful things like providing a count down timer which help as all our races are now measured as X minutes + 1 lap. Hmm I wonder if Tim’s DL1 software can display the current gear?

Or if I win the lottery use the Specific dash available for the DL1 from Race technologies, and maybe if I got amy arse in gear I could develop a little minidash of my own.

Preparation for the Birkett

I spent much of the day today doing preparation for the Birkett relay race in two weeks time, we have a set of team orders that requires such things as external battery hookups for start\boost batteries and general things like labels for tyre pressure and so on.

I also finally got round to fitting a gurney flap to the back bodywork, I’ve only been trying to get this job done for 2 years but it has always fallen off the bottom of the to-do list. Everybody in the paddockj tells me that this will glue the back end down, I guess my development as a driver is now getting to a stage where I’m beginning to be able to feel these sort of effects and want to do something about it.

Hopefully before the Birkett I can also get an engine bay floor fitted as I’m advised that this will further help to stabilize the airflow under the rear of the car. The other things that I managed to get under way today were some changes to the race van to try and improve its reliability. I fitted a new starter motor. it has a habit of not starting when hot and I think this has largely been due to the fact that the started doesn’t spin very quickly when hot. The volt meter I temporarily fitted a few weeks ago shows that when hot cranking the battery voltage drops to about 9v as the old tired starter draws a lot of current.

So I fitted a new started and it now spins much more quickly, doesn’t sound like it is labouring like the old one did. And when cranking the voltage barely wavers. All very goods signs, I also started a permanent install for the Voltmeter and Oil pressure gauges that I bought for the Van a couple of weeks ago. Hmmm the Birkett is really getting rather close now…. I can feel the nerves beginning to develop.

Progress Swinging Sump for Next Year

Today I popped over to see Nova Engineering. And had a good chat with Graeme about the CBR 1000 RR swinging sump system that I'll be using next year. A couple of useful pieces of information emerged. The first is that he would really like to be able to identify the sump pickup position during use this would require some sort of remote sensing application that watched the position of the pickup from outside the sump pan. Maybe a hall effect or magnetically driven sensor fitted to the outside of the sump (or a series of them at key locations. I don’t know id this is possible, but I’ll ask my electronic engineer mates on Cam7 to see if they have an easy solution that could be used. I suppose the key criteria are that it is light, tolerant of heat, easy to fit and cheap. Hmm not a difficulttset of design criteria then.

The other piece of information was that it looks like the GP sidecar boys will next year also be swapping to a CBR 1000 RR engines…. Or so the paddock gossip goes. The swinging pickup sump assemble is coming on nicely and should be ready in the next couple of weeks, which is handy as that is just after the Birkett and I’ll be looking at fitting the new engine in that timeframe.

A Fruitful Development Partnership

I've just a very fruitful visit to my local engineering company Nova Race Gearboxes. I found them while looking for a billet sump system for the CRB1000RR The owner is such a racing enthusiast so we spent a long time chatting about his Jedi racing and my RGB racing.

We also spent a good deal of time chatting about a CBR1000 swinging sump system he is developing, and his ATB equipped diff with engine driven reverse. He simply very keen to see his creations run in competition and by a midfield runner at that. He's not interested in guys chasing championshiops as they want to win at all costs and won't tolerate unreliability. What he needs is a development partner to feed back real world data and help him on the development curve for the items.

The upshot of all this is that he'll happilly let me run both the diff and sump on long term loan for free. His plans for the diff were eventually to give it mounting ears so that it can become a stressed member in the chassis, but it didn't take off after the Kit Car crisis fiasco. So it's just sat on the shelf.

Time to rekindle those plans me thinks.

The diff actually weighs around the same as my existing setup, but has three crucial advantages

1. Change of final drive ratio... I bet you could do this in less than 10 minutes, there is no necessity for split sprockets or other nasties. 6 allen head bolts allows the sprocket to be removed. And it has an integral cush drive too.

2. Engine driven reverse which doesn't need re adjusting after the sprocket is changed, and may actually move the car backwards... unlike my current system

3. Ease of fitting to the engine so that the sprockets are in the same planes. careful design of the CRB engine mounting system would take an engine swap down from a full days work to an
afternoon.

It would move a little bit of weight to the rear of the car, as the sprocket is not concentric with the drive shafts, but behind it to increase the chain length and its life. but as it is no weight penalty it seems an absolute bargain.

Whoo Hoo!

The last Day of Term

Today I went the the RGB meeting at Snetterron. I wasn't racing as I'd decided to skip it to save the engine for The Birkett in three weeks time. I love watching clubman racing as its so entertaining due to the different skill levels. Experienced old hands + novice new boys in their first races

I also picked up the front 3 bulkheads for the new chassis. From Tim Pell. Looking at the picture I suspect it is going to be fairly light weight :-)

The rgb races went well and some of the RGB mob were also racing in an closed wheel all comers race which saw stock hatch pitted against RGB cars and loads of other different machinery. So we all stood on the bank with the rest of the rgb paddock and cheered on our mates

The complete field was being led by a glorious bikesports Speed who led all the way until the last lap when because of waved yellows at Richies Chicane he slowed right down and was caught and passed by the second place Caterhan R400 while still under waved yellows. Overtaking under yellow is strictly forbidden and will normally earns you a good wigging from the clark of the course, disqualification and a licence endorsement!. Scandelously the race was awarded to the R400 and the results were confirmed.

Still with the remainder of the RGB field having a great time on the bank in the autumn sunshine cheering the RGB boys taking part in the last race of the year, there was a real last day at school atmopshere with lots of laughs. Everybody was talking about plans for next year and I'm now fired up with enthusiasm over the engine change and new chassis build .

It looks like Class B could be quite busy as several drivers were talking about engine changes and so on to get into Class B. But first comes the Birkett!