FAQs

Question:
What are my options for new camshaft profiles?

Answer:
There are effectively 3 options when it comes to Hayabusa cams:
1. Regrind a standard cam profile, this reduces the size of the cam in order to increase the lift and duration. You would then have to run a thicker shim to take up this difference. You are also limited by how much material that it is possible to remove from the original cam in order to produce a larger profile. We produce 2 profile designs; the first only require a pair of standard Gen1 camshafts. The second larger profiles require either a pair of standard Gen1 inlet cams or a pair of standard Gen2 cams because these cams have more material.
2. Hard weld on to standard cams, this is not something that we do. The problem with this process is that the material can sometimes then come off the cam profile causing damage to the cam and valve train.
3. Use steel billets to grind fresh profiles, which allow within reason any profile to be ground. The limiting factors are as follows, the steel billets are of a similar hardness to the follower so to prevent the 2 components wearing each other away, we would use either a DLC coating on the cam profiles or the followers to prevent any chance of this happening, but this is extremely expensive. The next factor is that as you increase the lift of the cams, the springs need to be significantly increased in strength. This creates extra load on the valve train, chain, guides, etc and also reduces their life.

The choice is dictated by your budget and the life expectancy that you hope to achieve, so if you want to do a drag run and have to rebuilt it every few runs, then you got for the biggest cam. If you wish to do a hillclimb, you go for something milder and if you wish to do sprints or racing, you look at something milder again.

Question:
I’m looking for a 100mm diameter dry sump oil tank because of installation issues. I noticed that the one on your site, but it says it can’t be used with a Hayabusa, why?

Answer:
The biggest problem with Hayabusa engines, in all bike engines, is the gearbox, clutch and generator areas in the engine. These can fill up with oil under different conditions e.g. cornering, accelerating, braking, etc which means that they can retain a lot of oil under these conditions and only when the area is full of oil and no longer any space, can it reach the bottom of the engine so be evacuated by the scavenge pumps. These creates 2 problems, most important of which is that you can end up with an excess of 3 litres of oil within the engine. The engine also normally retains between ½ to 1 litre when running. This means that you can end up with in the region of 4 litres of oil within the engine, so we have found the minimum capacity for oil within the dry sump tank needs to be 5 litres of oil (this excludes what is in the pipes, oil cooler and actually within the engine when running. Anything less than that will cause a problem, not just due to the lack of oil in the tank but the secondary problem which I will describe now.

The top of the dry sump tank is used to separate air from the oil, there will always be air extracted by the scavenge pumps and this can be up to 90% more air than oil. The oil is sprayed around the top of the tank and jetted as a film of oil around the wall of the tank. This helps the air to separate and by the time it is spun round the tank, the majority of the air is separated out. The taller the tank, the better this functions and the less complex the tank needs to be, the shorter the tank the less time available for separation to take place. Ideally you need a minimum of a 1½ litres of air space before the oil level is reached.

The tank we recommend for the Hayabusa engine is made taller than the original design, its first baffle has about 1.5 litres of air space, you can see the detail of the construction on the website. This tank is designed to separate air further as it passed through each level and the lowest level in the tank, in theory, does not allow for oil movement, but must be completely filled with oil only as any air left at this point would be compressed by the oil system and create catastrophic failure of the engine. This tank has an oil capacity of 5 litres, the smaller tank that you are looking at was originally designed for the Vauxhall engine in sportscars, the Vauxhall engine can run on 3 litres of oil in a tank, this meant that the tank itself has a large area for the air, it has no baffling due to its small diameter and its height. The Vauxhall engine only has small areas that the oil could congregate, so therefore would not retain as much oil as the Hayabusa.

If you do the calculations on a 100mm diameter tank, you require a tank in excess of 600mm tall and this is probably still not sufficient because you are more likely to require over 2 litres of air capacity due to the lack of baffling to allow the air to separate. Also due to its smaller diameter, you wouldn’t be able to incorporate the small internal design of the larger tank and without extensive testing could prove disastrous.

Question:

I have a 1999 std Busa engine that I’ve mounted in a custom made chassis. I plan to keep the motor stock as its fast enough for what I want. I’ve looked at your web site and think you have what I need to get it running?

I have all the original loom and ancillaries but it looks way too complicated and over the top. I would like a simple loom and I assume a new ECU. In time I want to have a power shift on it but that’s another budget. My idea is to have a paddle shift off the steering wheel.

Do your looms just plug in? What electrics do I need to save from the old loom? I assume I need a charging circuit and a ignition circuit? I’m not too worried about lights etc as these can easily be done on a separate switched circuit.

Also do I need to alter the charging rotor thing? If so is there an exchange option for this part? How does the old one come off?

Have you a full typical circuit diagram showing what parts of the existing loom/wiring I need to save? The engine does run, but I know it can be much simpler. In your loom do you cut out most of the silly sensors? Does the standard fuel pump (mine is on the back of the engine) plug straight in? Is it a simple plug in start up and go system?

Please can I have some advice, I don’t want to make an expensive mistake here.

Answer:

The installation of our system will be extremely simple by comparison with what you have there. Most of our harness will simply plug in to the original coils and sensors and what sensor you don’t require will simply be eliminated. The only update we have carried out recently to our wiring harness is to change the injector connectors to make them more user friendly for future engine updates, but it is a fairly simple process to either add or make simple adaptors to convert from the standard Suzuki injectors to our wiring harness (there is no cutting of our wiring harness). If you are OK with a heat gun and a crimp tool, it is no more than 1/2 hours work. There are instructions within the installation instructions of the kit that show you in pictures how to modify the connectors, which you would remove your existing harness or there is an option to buy ready finished adaptors.

The charging circuit is relatively easy to modify but we do make a simple charging harness, which simply plugs into the generator and the regulator pack and then gives you 2 wires for positive and negative.

Your original fuel pump can be used, the only issue you could potentially have is that on the motorbike the petrol tank is mounted above the engine and therefore the fuel is gravity fed to it. When fitting it to a car you would need to ensure that the pump is mounted lower or at least at the same level as the bottom of the fuel tank, so you may need to reposition it. Alternatively, if your budget allows, you could a more traditional supply and return system and replace the fuel pump, fuel rail and fuel regulator to suit.

The generator trigger wheel is easily changed with the correct Suzuki tool or if you are suitable mechanically minded, it wouldn’t be too difficult to produce something for yourself. Effectively you need to remove the generator cover, then there is a bolt retaining the generator rotor which locks it on to a taper and key. You simply undo the bolt, which exposes an external thread, the Suzuki tool is then tightened into this thread, there is then 2 flats on either side of the generator, which can be held with a spanner. This then pulls the generator off the crank, the generator itself on the early engines such as you have, has 8 teeth and you require a 24-1 which is fitted to the 2003 – 2007 engines and will fit directly with the Gen 1 generator. Alternatively you can fit the 24-2 trigger wheel from the Gen 2 engine, but you will also need the generator windings as well as the rotor because they are a slightly different size. We will need to know before programming your ECU. It is best to hunt through eBay or similar to look for a second hand unit, new units are available but are very expensive.

Once the system is fitted and the throttle position sensor is adjusted, which can be done with a volt meter, with the standard map loaded which we would supply in the kit, your engine will be ready to run and use. Please refer to our Instruction Sheets for the wiring harness fitting instructions.

It may be worth a phone call to speak to me directly as quite often questions you may feel are complicated can be simply answered on the phone. The system you are looking at is, we believe, the simplest on the market and we supply this kit worldwide to trade and retail alike. If you wish to upgrade your engine and other components associated with it, it can be easily done. You mentioned about Powershift, the standard wiring harness that we supply has a Powershift connector built in and the ECU will be programmed and ready to use it as standard. You can simply then order the Powershift unit, which you fix to the lever on the gearbox and connect the other end of the cable to your steering wheel paddle or gear lever.

Question:
I have a 2003 Westfield Megabusa with a 99 Hayabusa and it has your SBD dry sump pack. The oil temperature gauge never seems to get much above 65-70C on a trackday after circulating for 15-20 minutes. I suspected that the gauge wasn’t reading correctly, but I’ve tested it static and the reading on the pipe at the oil cooler is the same as on the VDO gauge, around 65C according to the temp sensor for my multimeter.

The oil system takes just over 6 litres and there isn’t a thermostat. I have an oil cooler with core dimensions of 360W x 193H x 50D, which to me looks very large for a 1300cc bike engine. The previous owner replaced the oil cooler, and decided to fit a bigger one on the “bigger must be better” principle!

I’m under the impression that the oil temperature should be around 100-110C when working hard. If so, what setup would you recommend in conjunction with the dry sump kit?

Answer:
If your engine is running the oil temperature you are seeing, this will be a first. Suzuki bike engines were originally air cooled, then oil cooled and then finally water cooled, but when they produced the water cooled version, it was effectively only added on top of the oil cooling design, which instead of virtually same amount of heat transferred into the oil system as in to the water system, hence the reason for running a very large oil cooler. Keeping the oil temperature under control helps to keeps the water temperature under control as well, due to heat transfer within the engine.

You have to remember that the oil temperature you are seeing is after it has been cooled, before it re-enters the engine and therefore it would be lower than if you measured the oil temperature within a wet sump for example. Normally cars such as sportscar and single seaters have space to mount the radiators and oil coolers on separate sides so they both get clean air flow and would be able to achieve efficient cooling. Normally on cars such as the Westfield, this is very difficult to achieve because all the air flow has to go through the nose cone and therefore either the oil system or water system will have an advantage. Obviously we don’t know your installation and how you have fitted the radiator and oil cooler, but if they are both achieving good efficiency, it is some that I am sure others including us would like to know how you have done it.

Since we don’t know how your installation is done, we can only give some basic advice. The Hayabusa itself is effectively a road bike engine, which has reasonably large clearances so it can be driven quite hard when not up to optimum temperature, otherwise they would be engine failures on the road bikes. As the temperatures rise the engine case expands, the clearances increase and the oil pressure will drop. When you get up to what would be called optimum oil temperature, when the oil is at its most efficient, the crank cases are potentially larger than would be optimal so we quite often like to see the engines running at a minimum of 60-degC and 80-100-degC, even though the oils can work at 120-degC the slightly lower temperature help to keep the bearing clearances tighter. Remember that the oil temperatures you are seeing, if correct, are after cooling.

Fitting thermostatic controls adds weight and complexity and not something that we try to do. Fitting a smaller oil cooler means you limit your cooling capacity and if you want to slightly increase the oil temperature, the common practice in all motorsport is to blank off parts of the oil cooler effectively reducing its size, you then have the ability to increase or decrease its efficiency very quickly. I would also check the oil temperature with a laser temperature gun directed at the oil in the tank from the filler cap just for piece of mind.

Question:

Hello, I’m looking for a for a bit of information. I’m running a Suzuki Hayabusa in stock condition. I’ve purchased your dry sump and tank which is working quite well. We set the engine up with dual radiators, and one single oil cooler. Water temps have been 170-180°F, oil temps have been 240°F and climbing. We have not allowed temps over 240°F. We’re not really sure what is normal oil temps for this engine, but were concerned were on the edge. Can you offer some info on this and some possible solutions?

Answer:

The Suzuki Hayabusa engine, as with many Suzuki engines, has evolved from the oil cooled engines and almost as much heat is transmitted into the oil system as the water system. The temperature of your oil at 240°F (116°C) is ok, but because the engine expands the bearing gaps increase dropping oil pressure. If the temperature could be kept closer to 230°F (100°C), this would help oil pressure as well. My suggestion would be to increase your oil cooler size significantly. You may also find that once you have managed to reduce the oil temperature, that this will also help to control your water temperature better as well.

When your engine is cold (oil temperature of 0 – 20°C) at tickover, I would expect to see between 50 – 60psi approximately and if revved over 100psi. Obviously this is not recommended until the engine is hot.

As the oil temperature rises, the tickover oil pressure will drop quite quickly and I would expect to see approximately 20psi when oil temperature is 60°C. As the engine is revved, peak oil pressure will probably be just under 100psi. I would recommend that you try and maintain between 80 – 100°C, this way your oil pressure at tickover will be in the region of 7psi and peak oil pressure 60 – 70psi.

The further the temperature rises, the lower the pressure will get, this drop in oil pressure is caused by 2 main factors; first of all the engine block grows dramatically with heat causing increased clearance between the bearings and the crank and secondly the oil itself gets thinner with heat, this is quite normal. If your engine was running a standard oil pump gear as opposed to our uprated gear, I would expect to see a 10% reduction in oil pressure throughout the range. It is not uncommon with oil temperatures in excess of 120°C being tickover oil pressure as low as 2psi and peak oil pressure down to 35psi. The most important thing to look out for is that the oil pressure follows the rpm, if you see any drops in oil pressure at higher rpm it is likely that your oil tank is carrying insufficient oil and therefore oil surge is occurring, which will cause engine damage.

Question:

What are the differences between the Hayabusa Gen1 engine and Gen 2 engine?

Answer:

The Hayabusa Gen 2 engine 1340cc has been around now since 2008 and therefore more readily available. The earlier Gen 1 engines were discontinued at the end of 2007, this means that the engines are now getting quite old and in shorter supply because of its popularity.

The Gen 2 has quite a few advantages over the earlier engine; the gearbox was dramatically improved and some of the shortcomings in the original design and the weak output shaft were overcome. The slight increase in engine stroke gives a nice improvement in torque and the engine having a better design of piston and higher compression has allowed the engine to produce the performance in standard form of a reasonably tuned Gen 1 engine and with the added advantage of the increased torque, a nicer all round package. The cam profile are also slightly larger, which helps add to this.

The downsides to the Gen 2 engine is that the valves are now titanium and they have seen failures in motorsport applications. Also the valve springs are now a single valve spring where the Gen 1 has a double valve spring, so a common modification is to replace the valves with either the Gen 1 valve or a stainless steel high quality replacement and fit the Gen 1 valve springs.

The barrels on the Gen 2 engine are windowed, which is fine if the bore size remains standard but if the bore size is increased, they will quite often fracture, so it is recommended for big bore versions that the Gen 1 barrels are sourced because they are much stronger but they are becoming harder to find due to their age.

The crankcase of the Gen 2 has been thinned around the area where the head studs or bolts fit into, this is normally not an issue unless you are using a turbo application.

Question:

I have got a Hayabusa 2004 Gen 1 engine with nothing special on it at the moment. Is running the 4 short airhorns is a better option?

Answer:

The use of a combination of air horn lengths has a tendency to smooth the torque curve, the longer air horns promote lower to mid-range torque and the shorter air horns improve the upper mid-range torque to peak bhp. If your engine is solely being used at higher rpm on the standard 1299cc engine, then potentially 4 short air horns will be the preferred option.

If you are using a long stroke engine in the future, then 4 longer air horns would be the best option for that engine because the engine does not rev as high.

Question:

I am currently working on a 1.6L Hayabusa and would value your opinion whether to use 4 or 8 injectors?

Answer:

The throttle body we designed for the Gen1 engine produced superior torque and power over the standard throttle bodies and during its design, we specifically worked on testing it against 8 injectors on the dyno. The end result meant that there was no advantage in running 8 injectors.

The Gen2 engine is produced with 8 injector set up as standard. We have tested the design on both 1000cc engines and the larger capacity Hayabusa versions. The standard throttle body set up with 8 injectors only increases performance when the upper injectors are used above 7000rpm and gives an increase of approximately 5bhp. The reason I believe the manufacturers have gone for 8 injectors is to allow them to move the lower set closer to the engine for emissions and then the upper set in an attempt to regain the performance that would be lost in doing so. When tested against the twin throttle body set up we have designed to fit the later spacing of the inlet ports of the Gen2 engine, we found we had a gain in performance everywhere over the standard Hayabusa throttle bodies.

So provided you are able to replace the standard throttle bodies with our throttle bodies, they will always give an improvement.