502 forum posts
How do you 'tune' a bike or an engine? I mean you would think that it was at its best when it came out the factory. So what does 'tuning' actually mean as in what do you physically do?
|michael darby||29/04/2016 19:01:36|
|44 forum posts|
Engines are "tuned" for different reasons, the car engines are set up to be reliable and economical. race engines are usually tuned for outright power.,which loses the reliability and economy. basically its about getting the largest charge,ie fuel/air mixture into the cylinder and producing the biggest bang. this could involve larger carburretor, longer injection timing,higher valve lift,longer valve opening timing and higher compression. but everything is a trade off more power means shorter component life more wear and less reliability.
2314 forum posts
It's long time since I've seen you post! - How are you doing?
4787 forum posts
The factory will set it so that it meets emission regulations in California, even if it is in Europe, (VW excepted) and not too much noise. Bike owners will then fiddle with it in a process called tuning so it makes more noise.
|Mike Poole||29/04/2016 19:40:08|
2185 forum posts
A cynical view Bazyle, but an exhaust can improve the breathing of an engine to take advantage of other improvements. The bolt on noise makers can be an irritation especially when not accompanied by the rest of the package to actually make more power.
Phil Irvings book 'Tuning For Speed' is a good read to cover the basics of engine tuning.
|Sam Longley 1||29/04/2016 20:16:17|
|727 forum posts|
Some time since I tuned anything but as far as I recall the following was standard practice for a car:-
Fluffy dice hanging off the rear view mirror, Go faster stripes down the sides , Peco exhaust booster, Spacers behind the wheels to make them stick out a bit, mix up the macdonalds wrappers in the footwells & remove the wimpey ones,spray some dark spray on the windows so you cannot see in (or out), lower the suspension so tyres rub on the wheel arches when turning corners. If you had any dough then stick on mag ally look a likes to the wheels, Leather steering wheel cover, rake back the driving seat so much that you are almost laying down, Hand holds over the rear windows ( to hook girlfriends feet in) Tracey & Steve sticker along the front windscreen (changed weekly) Couple of drops of castrol R in the fuel to make a smell, White rondals on the doors, preferably with castol emblem on one edge, never clean the car & just use wipers to clean the windows so it looks like you are straight off a rally, stick on bullet holes in the rear windows, & finally a tigers tail hanging out of the tank.
If you were real flash & had an old mini then cut the roof down so you could not get in it & grind all the guttering off. If you had a 105E cause your dad had dough, the fit a lotus twin cam & wide wheels, lower the suspension etc
All standard student go faster tuning tricks when i was a lad designed to make the 100E look quick Speed was irrelevant pulling the crumpet was the aim
Edited By Sam Longley 1 on 29/04/2016 20:16:48
Edited By Sam Longley 1 on 29/04/2016 20:20:26
|Neil Wyatt||29/04/2016 20:25:33|
16738 forum posts
That seems pretty accurate! You forgot "add extra switches to dashboard (not wired up)" though.
These days you just need a few blue LEDs or a scooby...
1624 forum posts
theres tuning and theres tuning. On a standard engine this would entail optimising certain settings to improve whatever you wanted to improve, for example one can sky rocket the power on common rail diesel injection units simply by increasing the line pressure by means of a crude resistor, but more likely the term is confused with modifying where components are altered to enhance a specific charateristic. Take exhausts as mentioned previously. The downpipe/manifold (header) can be tuned/modified/changed to alter the engine characteristics thus effecting back-pressure, speed of flow and resonance, this impacts engine response and power at different parts of the rev range. Couple this with a custom exit and silencer system and all manner of aspects are changed and affected. And as for the people with silly loud exhausts, they are almost without exception actually losing power on their road cars. The 'pipe' needs to be tailored to things like power range, cam profile and swept volume but to name a few.
1808 forum posts
A friend of mine picked up a new bike last week. A ZZR1400 performance sport version. He had a 2014 'normal' version previously to this.
When he picked it up he remarked to them that it was probably the quietest bike he had ever owned. - The reply accompanied by a grin was. "After it has been in for it's 600 mile 1st service I can assure you that it will sound a lot louder and be a whole lot quicker."
Is this a ploy to detune it for the running in period.? I doubt it as they will pull 0-200 in about 10 seconds and continue for a little bit more. So anyone who rode on the roads while caining it would probably never require that 1st service anyway.
I am not normally a cynical person but could it possibly be that bike makers (Kawasaki) are deliberately 'initially' supplying a detuned product to get around the emission tests.???
|Dave Halford||29/04/2016 20:59:45|
|486 forum posts|
I had a Peco once, the perforated tube came loose, and let the wool out and stopped the motor.
You forgot the clip on head rest and Hoddy Patkirk pointy door mirrors.
Oh and the furry dash and headlining.
Those with more sense welded a big windup key to the boot of a Moggy 100 mind you he did only have 2 wheel nuts on each wheel.
|Howard Lewis||29/04/2016 21:36:01|
|2439 forum posts|
Production machines are mass produced, and whilst compromising various parameters. it is surprising how much of an improvement can be made by just setting up the engine to specification.
(For many shops, "near enough" is often "good enough"; and some can't even manage that, making quite incorrect settings. You wonder if those folk could diagnose a flat tyre!)
An easy "improvement" is to match the ports, manifolds, and joints so that there is little or no step between them. Be careful in changing the shape of the ports, sometimes an apparent restriction actually improves the flow and Turbulence into the cylinder.
Sometimes, a small change to the shape of the combustion chamber can increase power.
It used to said that a prewar tuner of Rileys, Freddy Dixon, could add 5 mph to the top speed of a car just by stripping and rebuilding the rear axle. he was, effectively, "Blueprinting" the components. He was also an exponent of inlet and exhaust tuning
On naturally aspirated engines, improvements to the exhaust manifolding, will allow the use of a "tuned"system, with bigger advantage, if the pipework is low back pressure (ie Straight Through silencer rather than baffled. This will remove the high frequencies, leaving the pleasant low notes).
But be warned, "Tha gets owt for nowt", tuning the exhaust or inlet system to get ram at one speed, may well damage performance at lower, often half of that, speed.
The same can be said of changing valve events by altering the camshaft. There may be more power at higher revs, but a lot less torque at low speeds. If the power band is very narrow, you will need a lot of gear ratios to keep it on songl
And some engines need some backpressure, especially two strokes. Otherwise you can have worse performance and higher fuel consumption! In an extreme case the fuel carried into the exhaust could eventually explode, and blow apart the exhaust system
Also, tuning the exhaust system may well need revised ignition timing to maximise performance.
Avoid over advancing, as this will raise rates of pressure rise, and probably peak cylinder pressures. Peak maybe just a short "spike" which gives little extra power but can play havoc with gaskets, pistons, and bearings, and in the worst case the crankshaft or crankcase!
Enzo Ferrari once said that the ideally designed race car would fall apart as it crossed the finishing line; but I don't think that we are interested in going that close to the limits.
Also, remember that higher power has to be transmitted to the road, so the gearbox and final drive need to be considered. And having got the machine upto a higher speed, it has to be able to stop, handle and to take corners, so don't concentrate on the engine in total isolation; you are super tuning the complete vehicle.
In every case, you are balancing output against reliability and durability. The original VW Beetle engine was very reliable, (it was virtually impossible to over drive it), but as the capacity and power was increased reliability decreased. Some folk advised that to prevent valve failures, and extensive engine damage, the 1303 should have new exhaust valves fitted every 30, 000 miles. Apparently, the quickest way to break a crank was to increase the maximum engine speed. In my opinion, that was NOT reliable
Upspeeding any engine will decrease the reliability and durability of components, possibly just by extending the running range into the region where components go into resonance, and overstress themselves.
3463 forum posts
The easiest tuning example for me would be the 2.0 litre pinto engine they put into Ford cortinas back in the 80s
If you started tweaking that engine and bolting on grunty bits it could become an RS 2000 and even a rally competitor
Aye, them were days lad
3463 forum posts
Aero engine tuner Fred carter was famous for improving stock engines
747 forum posts
Many of the sports bike like Busa's are well tuned anyway you can alter the PC program or change the turbo and controls for such look at what Mick did with his Wife machine **LINK**
|983 forum posts|
It was stated on a Lotus/Colin Chapman profile that the statement re Race car dropping to bits immediately it passed the finish line was down to him? Explaining that if it didn't, it was over engineered.
This was of coarse when F1 cars had driver skill as the main winning factor.
When questioned, Jeremy Burgess, Rossi s Chief Mechanic at the time of the Rossi/Gibernau Honda battles stated that there were something like 95 different engine settings available and this was the difference in performance. Only one out made all the test results change.
Pity Seti never had Gerry in his camp.
713 forum posts
Talking of good books, A Graham Bell's "Four-stroke Performance Tuning" is also highly recommended. My copy was "borrowed" by a group of lads preparing bikes for racing, and I haven't seen it since. I'll have to buy a new one (£26.95 from Amazon). It's now in its fourth edition, so it should be reasonably up to date.
502 forum posts
Thanks lads, again things become a bit clearer
|Clive Hartland||30/04/2016 10:37:29|
2481 forum posts
Ady, that brings back memories with the Nordec engine. I was a junior member of the Medway Model Airplane club and enjoyed the help of more well off members who were into Control line models and Gliders. Also Wakefield models.
One time I saw a Nordec powered C/L model power dive as a line broke ! The tail plane was big enough for me to make a my own C/L model ! powered by an ED Bee. When I think back and how I spent my meagre monies on models and the like. Sold a Dooling 29 so I could get a new tyre for my M/Bike.
|John Coates||30/04/2016 12:05:51|
554 forum posts
|I've got John Robinson's two books "2 stroke tuning" and "4 stroke tuning" (he was the technical editor of Performance Bikes)|
Really good books with a lot of physics and maths but still explains the detail about the principles
Only tuning I did was on my 1999 Kawasaki ZX7R (which I still own) - K&N air filter, junked the clean air emissions crap, carb tune with new jets,emulsion tubes and springs, straight through ram air tubes, ignition advancer and after market end can.
Next stage would have been roughing the intake ports and smoothing the exhaust ports but never got round to that
|jason udall||30/04/2016 14:41:11|
|2012 forum posts|
|Not bikes but.|
Dave Visard "how to mod your mini"
And "tuning the A series engin"
Contain much of intrest
In any case tuning for power or economy have large overlap.
Simply put, off the line build will be set to nominal which will work for all tolerances.
Tuning of stock parts aims to get the best of "your" engin..
Now various mods improve your engine.
Better airflow in and out
Shove more fuel , In better mix state to take advantage of the increased air..
Improve ignition control. .timing..
Now chose economy versus power.
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