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Tech Time with :

Jamie Ron Dave Jim

 

TWO STROKE OR TURBO FOUR?

Hi Jamie,
The time has finally come time in my life to build a custom bike that I will never sell. I would love to build a YZR500 race replica, like the Gary McCoy replica [Rapid Bikes, July 2006] as I have a wrecked RS250 and I think that would be a good bike to share parts with. I would like some info as to who could build this or help with the build.
I am also thinking of a turbo ’Busa, but not a stretched one because I love track days. I’m thinking that S&R Pro would be the ones for the build. I have never seen a turbo ’Busa on a racetrack… I currently ride a 2004 ZX-10R so power is not an issue with me. Your advice would be appreciated…
S Campbell, email

JamieHi mate,
It all comes down to how much money you want to spend and how fast you want your custom bike finished. As for a track bike I would sugest doing your wrecked RS250 but it would take a long time to finish off and it would cost you a lot more money to do. I am not to sure on were to start on this bike or who to ask about building it but micoproducts.com is a start. Now as for a turbo ‘Busa I can help you here. It would take about four to six weeks to do the turbo kit and you will have over 240-horsepower but you will have to do some serious suspension work on the bike to get it handle on a track with that type of power. Also we would do a custom raditor that is a lot larger to handle track work. Your ZX-10R would also be a great bike to turbo and would be an even better track bike than the ‘Busa and it will take the same time to turbo kit and you will get the same power if not more – Jamie


BANDIT POWER

Hi Ron,
I own a 2008 Suzuki Bandit, which I’m looking at upping the horsepower without spending the big dollars. I’m thinking of a slip-on exhaust like Yoshimura (or similar) and maybe also a performance ECU. I’ve heard that if you go for the exhaust option you have to remap the ECU. Is this true, or is it best to leave the ECU alone?
Robert, email.

RonHi Robert,
For the best results it is always advisable to tune the bike to any mods you have done. This is where the dollars come in. If you fit just a muffler to the bike, you might get away without tuning but you could have some backfiring and a slight flat spot in the rev range. You might not, every bike is different. Either way, there is not a huge horsepower gain to be had from just an un-tuned muffler. For more horsepower you will need a full system and something fully tuneable. It will save a lot of weight, look great, sound great, and go a lot better but it will cost you. You’ll be looking at between $1000 – $3000 for the exhaust and installation, and an extra $1000 for tuning. So if that’s too much of a turn-off, it’s OK to just buy a muffler and stick it on and see if you need to tune from there. Keep a high-flow airfilter in the back of your mind too – Ron


COOLANT

Hi Ron,
I was reading the December/January issue and noticed that you used Liquid Performance coolant in the long tern ZX-10R. Is this legal for racing and if so, who is the Australian distributor? I figure this has to be better than distilled water, which keeps boiling on me when I pull into the pits during the summer months.
Bill Evans, email

RonG’day Bill,
LP Antifreeze is imported by Warrian Enterprises on (07) 3279 4500. As far as I know, no coolant is legal for racing at the moment. Coolant producers have been trying to butter up the Australian Race organisers but, understandably, they won’t have a bar of it. Straight water on the racetrack surface is fine, but coolant is very slippery and too much of a liability. There is not much you can do in this case, but not many racers suffer from that problem. Cooling systems are good enough today to keep engines at a moderate temperature with water when the bike is at speed, but as soon as you slow down or idle it can’t cope.
If you still have a fan on the bike I’d check the temperature switch and thermostat. But if this is happening in cooler months too, you might be able to richen up the fuel mixture a little bit to help cool the engine a bit. You’ll lose a bit of power but the engine temp will be more acceptable. One thing a lot of the race teams recommend is to do a cool down lap before you come in, so that the bike is getting air flow without high revs. Give that a try – Ron


MAPPING EXPLAINED

Hi Dave,
I’ve been riding for 20 years and always do my own servicing. I can service carburettors, valve clearances, do most chassis work but I have no idea about EFI. Let’s just say that I’ve only just come to grips with my mobile phone let alone this computer! So, can you explain the fundamentals of an EFI system and the tuning process? I ride an SV1000.
George, email

DaveHi George,
Fundamentally, the fuel is electronically injected under extreme pressure into the inlet airflow of the throttle body in millisecond-timed pulses on the inlet stroke of the engine. To tune this we use a piggyback control unit (Power Commander) that allows us to lengthen (richer) or shorten (leaner) the millisecond pulse. For example, across nine throttle positions, from 0 to 14,000rpm in 250rpm increments the equation is 56 points x nine throttle positions. That gives 504 places to tune the length of that pulse. Then with your SV1000 twin, double that job as we can do the front and rear cylinders separately for an extremely fine tune – Dave


NEW POWER COMMANDER ON THE WAY?

Hi Dave,
I heard there was an all-new PC on the way with fuel, ignition and auxiliary capabilities. Is this true? Is it a complete replacement ECU?
Brent, email.

DaveHi Dave,
The new PC V (5) is still a piggyback unit. Dynojet has started with the Harley Davidson range with other brands to follow but it will only be for bikes made from 2009 onwards. In advanced mode, it’s possible to run 24 individual fuel tables! Check out www.powercommander.com/ powercommander_hd/ – Dave


PICK OF THE BUNCH

Hi Dave,
I am pretty sure you are not affiliated with any brands so, in your expert opinion, what is the pick of the bunch of the current 1000s in terms of engine performance and gains through minimum spend. For example, pipe, airfilter, PC and mapping. I need a powerful bike. It’ll be my only transport and I do track days.
Andre, email.

DaveHi Andre,
Crikey! Twin or four, Jap or Euro? It would be fair to say there is not a lemon among them. Your budget you must allow about $2000 – $2500 for your bits and $3000 – $3500 if it needs twin mufflers. If you were on a tight budget then a good starting point would be a Suzuki Bandit 1250. Good value for $1100 – $1200… – Dave


RE-CHROMING

Hi Jim,
I have an old GSX-R750 and need to have the fork inner tubes re-done. Can you recommend anyone in NSW?
Thomas, email.

JimHi Thomas,
Yep, A1 Hard Chrome Pty Ltd, (02) 9648 5299. They are not the cheapest by any means; but they do good work – Jim


R1 FORKS

Hi Jim,
What is the advantage of the 2009 R1 forks over standard forks? Are having the damping circuits separate a new thing or old? I seem to recall another bike with this set-up, an old Maico dirt bike!
Derek, email.


JimHi Derek,
As far as road-machines go, yes it has happened before; usually with Guzzi’s and the like – I have done it to a few of my Honda’s as well; and Ohlins had three years worth of FG Racing forks with the facility too, as far as I can remember (FG4, 5, and 670).
The advantage over a standard fork is debatable really, as in some ways it’s good due to the fact you are able to adjust it without bending down! Because it doesn’t work like regular-type compression base valve damping, it is a little contingent on its internal setting, being spot on for the application at the time (the who and the where). Plus, they usually tend to ride higher in the stroke on average, which some will not adjust to as well as others.
A revalve or a more regular approach to fluid control will be more suited for some riders. It is a different sensation that some will love and others not. However, my comments are really based on the other previous guises for this design, because I have not seen inside the 2009 R1 (aside from Ohlins’ race-kit stuff) fork yet; so am not properly able to pass comment as to whether they have done it well or not! – Jim


RZ500 SET-UP
Hi Jim,
I own an original RZ500 after many years saving. I have been warned by all of my mates about these things so want to get it set up as safely as possible. What are your recommendations?
Gary Taylor, email

JimHi Gary,
It is highly likely that if it has a few kilometers on it then the shuttle valve within the fork will be quite worn; and this will affect your damping, which is largely noticeable from it becoming quite vibrant and bouncy over uneven surfaces. Naturally, having fresh and appropriate viscosity oil in them will help a bunch too! In any case, the spring rate is quite low; so a good set of springs and preferably some adjustable valves under these would be the most cost effective of cures. Beyond that is to fit an entirely different fork/front-end…
Ironically, the rear shock which sits underneath the lower exhausts might seem hard to do anything about, and it is not itself a serviceable item; but what I mean to say is that fitting another shock in there is fairly straight-forward – there is even a certain Honda shock that I have used before with just a simple spring swap to it…
I would do something about the front fork first and foremost, and depending on the shock’s overall condition, consider doing something with that too. Because they sit so low in the bike, they really do cop a lot of grime from the road surface as you pass over it. Good luck with it, and what a grand machine! I can remember riding those in the 1980s and thinking they were totally wicked! – Jim


STROKED
Hi Jamie,
After reading dyno time I have been wondering if it is possible to successfully turbo a two-stroke engine. I have found articles on turbocharging two-stroke diesel engines for marine applications but not much on petrol engines. The little bit I have found states that turbo charging a two-stroke doesn't destroy all exhaust resonances but you have to place the turbo after the expansion chamber and match the turbine and housing carefully against the resonances in the pipe. Would running a passive exhaust be an option? If possible, what type of turbo would suit?
Dean Riordan, Warwick, Qld

JamieHi Dean,
Yes it is true, turbo charging a two-stroke doesn’t destroy all exhaust resonances as long as you place the turbo after the expansion chamber and match the turbine and housing carefully against the resonances in the pipe. Running a passive exhaust on a two-stroke engine is not a good idea as you are restricting the standard power while not on boost. It’s hard to say what turbo would suit as I need to know a few details like the size of the engine, what the bikes rev range is, what size carby's etc. I have turboed an old 1985 model RG250 that made just on 80 horsepower and ran a 1/4 mile time of 12.5@118mph. The turbo I used for that was a small IHI turbo with a modified exhaust housing.


NATURALLY ASPIRATED
G’day Jamie,
Your Hayabusa is 500-odd horsepower but how much power would it have without the turbo? The reason I ask this is because I am considering building a ‘Busa (I have a wrecked one) but I want to stay naturally aspirated while still getting big power. How far can you go with a ‘Busa without turbo power?
Ian Aitkin, Auckland, NZ

JamieHi Ian,
If I took the turbo off my bike it would only make 140 horsepower which is less than standard. The reason for this is because it is a low comp motor and the whole motor set up is for turbo only. To get big power out of a ‘Busa, naturally aspirated, you can get around 300 horsepower. But it’s not suited for street use, as you would need to run the bike on race gas. The reason for this is because your compression ratio would be sky high and it would not be very smooth due to the amount of engine work needed to get this power.


DRAW THROUGH
Hi Jamie,
After reading Rapid I am seriously considering my own turbo
project. However before I start I would like to know how hard it is to set up carb's for a turbo and what's really involved. My project bike would be a ZX-7R. Is there any well-known weaknesses with the 7Rs motor or ‘box that would definitely need attention or is it a straight bolt on affair?
Mark, Deception bay, QLD

GJamie’day Mark,
Setting up carb's for a turbo is hard. The reason for this is everything works in reverse. Boost pressure forces fuel back to the tank and to fix this problem you will have to get a fuel pump capable of running at least 3-4psi over your desired boost pressure and a good fuel pressure regulator to do this. You would have to find some way of getting boost pressure to your fuel bowl and blocking off any air leaks on your carbie. After doing all this you will have to do a lot of dyno time to get the desired air fuel ratio needed for turbo charging. As for the ZX-7R running around 7psi boost shouldn’t be a problem for the bike provided it is in good mechanical order. You should expect to get around 180 rear wheel horsepower.


STORM TROOPER
G’day Jamie,
I recently purchased a 1998 Honda VTR1000 Firestorm as a project and on the things to do list is an engine rebuild. From information I have been able to find it seems the cam-chain tensioner is a real problem on these engines. It has been suggested that a CBR tensioner is the go and can be fitted. What are the options to fix this problem? Also, what other modifications are the go on these engines? From what I have read they seem to be pretty good and people don't mess with them too much. I have a pair of Staintune exhausts to fit and intend to get some later model inlet manifolds which are a different size (and apparently improve airflow) but apart from that what do you suggest for a motor that will only see street duty?
Shayne Faulkner, Brisbane, Qld

Hi Shane,
To be honest I haven’t had that much to do with the VTR1000 Firestorm but what I would suggest is to source a cam-chain tensioner off a later model VTR1000 Firestorm as one would hope the manufacturer would have fixed the problem. For other modifications the norm is an after market exhaust system, K&N air filter, Dynojet kit and a few hours on the dyno should give you about a 12 horsepower increase. As for another option a NOS kit and an after market exhaust system and you could get around a 40 horsepower increase depending on fuel quality. With the different size inlet manifolds, I can’t say, as I have not dyno tested them to see if there is any difference.


WET ONE
Hi Jamie,
Why do people use water injection in some turbo engines? What are the benefits and why?
Ben Young, Melbourne, Vic

G’day Ben,
Water injection is used to stop detonation on turbo vehicles or high compression vehicles. Your vehicle shouldn’t need water injection unless you have a badly designed combustion chamber, bad quality fuel, too high compression ratio for street fuel or too much boost. Basically water injection is a cover up for not doing the job right the first time.


DUCATISTI
Hi Jamie,
I own a Ducati 999 that is stock except for a carbon fibre clutch cover (woohoo).
The bike is superb in its current state and plenty powerful enough but I would like to add a set of pipes, mainly for the noise. However, owning a Ducati seems to imply that you have no brain but lots of money.
I have been told that you can’t buy a second-hand set of Termignioni pipes without the matching CPU and air filters. Sure you may be able to locate a second hand set of pipes for about $1000 but the CPU will cost another $2000! I have also been told that the Termi pipes + ECU + filters are the only ones that will really benefit the bike.
However, I have also been told that a second hand set would be no problem.
So can I fit a second hand set of Termi pipes to the bike without the factory CPU and overcome this by fitting a Power Commander?
For a straight talking magazine like Rapid, this should be a no-brainer.
Peter Pyriotis, email

Hey Peter,
You’re right, this is a no-brainer. I have always thought that some Ducati riders get mislead when it comes to after market parts that aren’t made by Ducati. You don’t need the factory CPU, you can use any aftermarket computer such as a Power Commander, S&R PRO Interceptor, Motec, Haltec, MicroTec, etc. And the bike can be tuned with ease. You can also fit different exhaust systems, or anything else for that matter, like turbos, NOS and superchargers. Your bike is no different to any other bike.


SUPERCHARGED FJ
Oh Great Bezzina enlighten me with your words of perverse horsepower wisdom. I’m about to start a project supercharged FJ1200 and I have a few questions. Do I get better drive off gear or chain drive and how far will I have to modify the fuel system.
I'm an older (48) biker and it really gives me a buzz blowing away the new bikes on an old sport tourer at the lights. I know I could buy something off the showroom floor but where would the fun be in that?
Paul Galna, email

Hi Paul
You will get better drive off the crank using gears as there is no lag or chain stretch. In regards to power and performance using either gear or chain it is very hard to notice the difference. As for the fuel system it’s hard to say as I need to know what boost pressure you are running and what fuel you are using to determine what the right set up for your bike is. As a rule, 11.7:1 AFR is a very safe ratio to start with. This way you will make power without doing engine damage.


PULP or ULP
G'day Jamie,
I have owned six bikes in the last 15 years and my latest is a 2001 R1.
I've been obsessed with motorcycles all my life and it's good to see I'm not alone. I Love the R1 and was wondering
if there is anything I can do to improve the exhaust note without replacing the muffler? My other question is about unleaded fuels. I have tried both ULP and PULP but I can't notice any real difference in performance. Is it OK to run standard unleaded?
Scott Woodroofe, Adelaide

Hi Scott,
For the first question, yes you can modify the exhaust and get power increases but I would not recommend you doing so as it is highly illegal and you could cop a fine for $10,000 from the EPA if and when you get caught. For the second question you will make more power on standard unleaded as it burns faster. The higher the octane the slower it burns, the lower the octane the faster it burns. If you run a high compression engine (most modern sportsbikes, including yours) you should run high-octane fuel because it burns slower and has less chance of detonation. Thus giving you less power but better fuel economy. If you have a lower compression engine you should run low octane fuel, as it will burn faster giving you more power at the risk of detonation.


BIG BORE
Hi Jamie.
I have a Yamaha SRX250. It handles superbly but has no guts. I am considering putting a 350 top-end off an XT or TT 350 on. My question is, will I need to adjust the weights on the counter-balance shaft?
Tim, email

Hey Tim,
The answer is yes, you will have to get it balanced and you will notice a great difference in torque rather than horsepower, which is what counts anyway (torque sells bikes, horsepower wins races).


FUEL CONFUSION
Hi Jamie
I'm new to riding and have recently purchased myself a Suzuki GSF250 Bandit. I'm enjoying the time I get to spend on my bike however when I fill up my bike I'm getting confused between the various types of fuels that are available. It seems every service station has a different type of premium unleaded with a different octane level. Is there any difference between the many types of premium unleaded fuels that are available and is there any particular type or octane level that would be better to run in my bike?
Rebecca Pethybridge, Bendigo, Vic

Hi Rebecca,
With a bike like yours (low compression) I would suggest sticking to the standard unleaded (see PULP or ULP question). This will give you more power as it burns a lot faster than premium unleaded.


BUDGET BLADE
Hi Jamie,
I currently ride a CBR250RR that I bought for only $600 and have done up for $2000. I now have a great L/P plater bike. But after riding for around a year now I find the bike a bit slow. I was just curious to know whether you could help me with some ideas on how to get a bit more from the bike with out breaking the budget?
Josh P, Sydney, NSW

Hey Josh,
Unfortunately there’s not really much you can do without spending a bit of money. Buying an after market exhaust, which will give you anywhere from three to five horsepower extra (after tuning) will set you back around $600 is the cheapest thing I can think of.


 

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