Ok people on this site told me to properly warm up to about 40-60 on the temp gauage.. its about 18 degrees here in tokyo...and to warm up to that temp it takes about 6-8 min.. my mechanic said dont warm up cuz if i do my plugs will get wet because i'm idling the engine.. He laughed when i told him that i was warming it up to 40-60.. he said just kick start it put on **** helmet and go..
Which one is it? i'm very confused since i'm still a newb..
If your pilot jets are set correctly, they should not get wet.
Your mechanic has a vested interest in your bike going bang - we don't! _________________ MC21SP Plaything
BMW F800GS Bumblebee
Triumph 9551 Daytona Big boys toy
FJ1100 Sporting relic
GTS1000 oddball
also its not ideal to just let it idol at tickover (so i am told) when i warm mine i blip the throtle every few seconds. _________________ MC21SP - Roth-tax
CBR400 - track
MC21R - sold
MC21SP - sold
nsrmonkey wrote:also its not ideal to just let it idol at tickover (so i am told) when i warm mine i blip the throtle every few seconds.
DO THE MONKEY
no matter what bike you have its always a good thing to warm it up, I normally start my bike put jacket and helmet on, blip the throttle for a few mins then ride off slowly down the road, after a few miles its at operating temprature BUT i must stress i always ride real slow, but BEst practice would be to get her warm first, blip the throttle and be happy, I dont want to insult your mechanic but ask someone else for an opinion, most tunning companys in the UK will recommend that you warm any bike up before riding it, Im fairly new to NSR's as well i got mine in may and this forum has been spot on. there hasnt been a bad bit of advice yet!
People that start up a 2-stroke, and ride away at cold really make me shake my head. Mechanics that tell you to do it need to be hung up from the testicals!
Here is how I warm up my NSR...
1. If you got a choke, put it on.
2. Twist the throttle one or two times.
3. Kick the bike until it starts (shouldn't need to really give it throttle at this time).
4. Once it starts, let it "warm up" for a couple seconds or more before really throttling it.
5. Once it's ready for some throttle, you can blip the throttle, not really bringing it past 4K until it's got some heat in it. (for my RS, I actually hold it at like 3.5 for a little, then 4 for a little longer till it's around 50 degrees.)
6. Once I get it around 50 degrees, I then blip the throttle to nothing more then 5K, or hold it at around 4.5K till it's at temp, then I give it a good throttle to clear things out, and it's ready to ride.
It`s just my opinion,
I think everyone`s getting a bit over cautious with this warming up procedure.
Each to his own but, I think this guy`s mechanic is just saying that you can ride off safely straight away, as long as you don`t put the motor under strain by chugging up a hill in top gear at 1500rpm. Or by screaming away at max revs everywhere.
Gentle riding until the engine warms up, as far as my experience goes shouldn`t cause any problems.
I used to warm up my race bikes religiously, as you lot do with your bikes but, only because I was going to scream away from the start at full revs.
On a cold two-stroke, racing starts, followed by max rev riding are the best way to a cold seziure.
Not necessarily the case for a road bike.
So, if you take it gently until the engine has warmed up, there shouldn`t be any problems.
Like I said everyone`s got their own methods, doesn`t mean one way is more right than the others.
Chester362 wrote:I think everyone`s getting a bit over cautious with this warming up procedure.........................Gentle riding until the engine warms up, as far as my experience goes shouldn`t cause any problems.
.
Just a wild stab in the dark here...........you never cold seized an engine did you?
My rule is the '28 doesn't move till the temp gauge says something (display comes on at 35*), leaving Monkey's at night rather than sit outside his house annoying all the neighbours I push it along the road blipping as I go until it's warmed up.
Using any engine cold is wrong, their religious warming up of engines is supposedly the reason that Honda engineers never found any problems with the original VF750 V4 diesel lump, using a 2 stroke from cold is asking for trouble. _________________ Please do not PM me technical questions, if you can't find it on the Forum start a thread
4. After the engine starts, run it for a few minutes, "blipping" the throttle untill it is warm enough to idle with fuel enrichment knob lowered. The knob should be lowered as soon as possible to prevent spark plug fouling.
5. Do not rev the engine more than necessary or engine damage may result.
6. Warm the engine for a few minutes until it is heated to operating temperature (untill engine responds to throttle smoothy) (water temperature at 60 deg)
7. Under no circumstances should the engine be driven at high speed (full throttle) under no load. _________________ If I have to take the carbs off once more...
This is an interesting article on seizures on 2-strokes (watercraft but applicable)
Some fundamentals - Many people believe that piston seizures occur when engine heat causes the piston to expand larger than the size of the cylinder bore...this is not true. If you could freeze your engine "in motion" in the middle of a long full throttle pass, and disassemble it for micrometer measurement, you would find the piston to measure at a .0005" to .0015" press fit into the bore. That's right, a slight press fit! The reason that it doesn't seize is because the premix oil has such a terrific film strength that it acts as an irremovable buffer between the piston and the cylinder. That is, the bare metal surface of the piston never actually touches the bare metal surface of the cylinder because the oil stays between them. Many mechanics have experienced this phenomenon while cleaning a freshly bored cylinder. Completely dry without cleaning solvent, the piston moves through the bore with difficulty. After rinsing the piston glides all the way through with no resistance at all. This is because the solvent acts as a film between the piston and cylinder.
A piston seizure can only occur when something burns or scrapes away the oil film that exists between the piston and the cylinder wall. Understanding this, it's not hard to see why oils with exceptionally high film strengths are very desirable. Good quality oils can provide a film that stands up to the most intense heat and the pressure loads of a modern high output engine.
The difference between seizure and scoring Seizure and scoring are two different stages of the same problem. When the oil film on a cylinder is momentarily burned or brushed away, the metal surfaces of the piston and the cylinder wall will actually touch. When this happens, there is a sort of scraping that takes place between them. When the oil film is resumed, the marks from this scraping will often remain on the piston and (or) the cylinder wall. This momentary scraping or "scoring" seldom causes any permanent or performance robbing damage. No significant damage takes place because the oil film is resumed before the piston and cylinder have a chance to start exchanging material onto one another.
Scoring is commonly seen on the piston face directly below the piston ring end gaps. The blast of combustion can get between the large end gap of a worn out ring and burn the oil off the piston and cylinder in that area...Hence the surface scoring. In most cases, score marks can simply be sanded off of the piston and cylinder. However when ever you see scoring, it's a good idea to find the source so that it doesn't develop into a full blown seizure.
Seizure is a case of scoring where the oil film does not immediately return. After a few moments of constant scoring, the piston and cylinder will scratch each other hard enough to remove material from each other. This floating material grinds itself into the piston and the cylinder as it continues to grow in size. As this snowballing material grows, it will drive the opposite side of the piston against the cylinder wall with a pressure so terrific that scoring begins to take place. While all this is going on, your engine is still running wonderfully at full throttle.
The death blow comes when the mass of material between the piston and the cylinder wall finds it's way to the piston ring. This nearly molten mixture of aluminum and iron will instantly lock the ring in it's groove. This ring locking, not the piston surface seizure, is what actually causes your engine to quit. When the piston ring becomes locked back in it's groove, it's incapable of providing compression sealing against the cylinder wall. This instant loss of compression, while the engine is at speed, causes a dramatic loss of power. That power loss, along with the added drag of the badly seized piston, makes the engine quit or lock up in a nanosecond. In fact this entire seizure process, from the first scoring scratch to the piston locked solid, takes less than a second at full rpm. That's not even enough time for you to utter the first syllable of your favorite profanity.
There are many different causes or sources for piston seizure. Each cause has it's own symptoms and it's own visual results. The following is a description of several very common types of seizures, and the most common problem source for each one. It should be understood that diagnosing piston seizures is not done with any precision by even the best engine builders. However this information may allow many of you to make a more educated and accurate guess.
Four corner seizure - This is by far the most common type of seizure found in personal watercraft engines. Both sides of the piston will show heavy scoring and seizure marks on each side of the wrist pin hole. The pattern of these four seizure points often appears to be a perfect square, hence the slang term "four corner". The scoring takes place in this pattern because those areas of the piston casting are the thickest. When the piston is seriously overheated, the thick areas will expand and distort the most. High output motorcycle engines usually experience this type of seizure pattern when a piston has been fitted with too little clearance. Most experienced , and well meaning, motorcycle mechanics would take one look and immediately say that insufficient piston clearance is the cause. However that diagnosis, on watercraft engines, would be wrong about 99% of the time.
Four corner seizures in watercraft engines are almost always a result of the engine creating more heat than the cooling system can exchange away. That is not to say that most cooling systems are under built, but rather that it's easy to make a modification that creates too much internal heat for even the most beefed up cooling systems. Even though a constant feed of cool water is being moved through the cooling system, the cooling system must be capable of exchanging the engine heat away at a rate quicker than the engine is creating it.
The engine factors that have the greatest seizure related effect on operating temperature or excessive compression ratio or ignition advance, high rpm, insufficient fuel octane level, insufficient cooling, or any combination of these. Properly adjusting these same factors will have the greatest effect on total power output. The job of the professional engine builder is to find the right combination, or "blend", of these factors that will result in strong overall power output at a pace that your cooling system can keep up with. There are many mechanics and engine builders who have mastered their own combination "blend" that can get you all the power your after without risking a seizure.
A group of mismatched modifications is a first class ticket to "seizure-land". Any inexperienced individual who sets up your engine with over 200 psi of compression and advanced timing, is also guaranteeing your arrival. If your big mouthed motorcycle buddy down the street tells you that he can make any engine "roost"...you should think twice. You could be in for a very expensive lesson.
Lean seizures - Despite what most people think, lean fuel mixture seizures on personal watercraft engines is actually a very rare occurrence. The high speed circuit on almost all personal watercraft carbs is responsible for delivering fuel in the 30%-100% throttle range. If the high speed circuit is lean enough to cause piston seizure, it will also cause an almost un-ridable hesitation or laziness in mid-range throttle response. Dangerously lean high rpm racing motors can sometimes offer acceptable mid-range, however they will accelerate to peak speed very slowly.
The classic lean seizure exhibits heavy scoring and seizure along the entire width of the exhaust port with only light scoring on the opposite piston faces. In lean mixture conditions, the exhaust gas temperatures escalate quickly into the meltdown stage. Those high temperature gases can compromise or completely burn off the oil film on the exhaust piston face as the exhaust port is being covered up. With the oil film weakened or gone, scoring quickly turns into seizure and ring locking.
Air leak seizures - These are very common seizures because air leaks themselves are so common in watercraft motors. If you could pressure check every engine that showed up at a local racing event, you would find over 50% of them to have an air leak. Because of the varying degree of these leaks, some will result in seizure, others will only cause poor carburetion or slight overheating. The varying effects of these air leaks makes this a difficult diagnosis.
In any situation where an engine has seized for no apparent reason, the motor should be pressure tested before any other teardown work is performed. If a mechanic does not have the equipment to pressure test your seized engine, it's very unlikely that he will have the finesse to accurately diagnose your problem either. In fact, pressure testing should be a standard finishing procedure for any major engine reassembly work. Race engines should be pressure tested no less than every 20 operating hours.
The air leak piston seizure, depending on the severity of the leak, can look like a four corner type or a lean mixture type of scoring pattern. If an engine is operating on the ragged edge of overheating, a small air leak can easily cause the extra overheating that will result in a four corner seizure. On the other hand, a huge air leak will draw in so much additional air that even an over rich engine can experience a lean type seizure at full rpm's.
Detonation seizures - If a modified engine has been prepared with too much compression or spark advance, or if it's run on unacceptably low octane fuel, it will begin to "ping" or detonate. Detonation is a big subject the merits another article of it's own. For now we only need to understand that it causes a terrific amount of internal heat in a very short time, as well as physical damage to the combustion chamber. If you have ever seen the outer diameter of a cylinder head dome that looks as if it's been eaten by termites, you have seen the results of detonation. It packs a physical force that is roughly equivalent to hitting the edge of the piston crown with a full arm swing of a ball peen hammer. In a short amount of time, this detonation pounding will collapse the ring land and lock the ring in place (usually on the hotter running exhaust side of the piston). As soon as the ring is locked, the flames of combustion burn the oil film off of the cylinder wall, and the scoring/ seizure process begins. Because of the exhaust side scoring and the swift overheating caused by detonation, you'll have a 50/50 chance of a four corner seizure or a "lean mixture" appearing seizure. Only an experienced watercraft engine builder will be able to accurately diagnose this seizure source.
Cooling system seizures - This cause cuts into the gray area of piston seizure. A clogged cooling system on any machine can cause swift and serious temperature problems. However, no engine will ever experience a seizure purely as a result of inadequate cooling from the stock system. I have seen several 50+ mph modified boats run an entire trouble free season with a bone stock cooling system. These engines are not a statement of the effectiveness of the stock cooling system, but rather a statement to the benefits of having a professionally prepared high performance combination. The larger line and dual line cooling kits certainly have their merits on high output race engines that will be run at full throttle for extended periods of time. Their ability to more rapidly exchange away engine heat is a great asset on modified engines that are run at full throttle only. However, none of them can exchange away the excess heat created by a poorly prepared engine package. If you are experiencing chronic piston seizures of any kind, increased cooling may temporarily stave off the problem, however it will almost never cure it.
Piston clearances - As mentioned earlier, too little piston clearance is one of the most common "wrong" diagnoses made on seized watercraft engines. Most of today's watercrafts come brand new with cylinder clearances that are .001"-.002" over the recommended factory setup clearance. This extra clearance is an added protection against riders who don't follow the proper break-in procedure. If the clearance of a bored cylinder has been set at the factory recommended clearance, the close piston clearance by itself will not cause seizure. There is usually an added factor such as excessive compression or an air leak. If a piston if fitted with too little clearance, it will usually experience a four corner type seizure pattern. In most cases the ring will experience little or no damage. If this is the case, it's entirely safe to sand the score marks off the pistons and re-use them in the freshly honed cylinder.
Too much piston clearance can also result in piston scoring and seizure. A piston ring, in an excessively large cylinder bore, will have a very wide end gap not to mention very weak ring tension against the cylinder wall. The flame of combustion can easily burn past this weak ring seal as well as down the end gap opening itself. If this flame burns off a significant amount of the oil film on the cylinder wall, the scoring seizure process begins. Piston seizure caused by excessive clearance is much more common than you might think, particularly on iron cylinder 550's.
Break in seizures - The most common break in related seizure is usually caused by the ring not the piston. Most new piston rings come with a gray or green Teflon coating on their outer sealing surfaces. This coating seals to the cylinder wall in just a few operating minutes, which provides better power during the break in period. As the engine is breaking in, the Teflon eventually wears away and lets the hard surface of the ring come in from behind to provide the long term seal. The down side of this Teflon coating is that it makes for a dangerously small end gap during the first hours of operation. If the engine is run too hard too soon, the heat will cause the ring to expand in diameter which will drive the ring ends together and drive the ring surface hard against the cylinder wall. A piston ring that is being overheated in this fashion will easily have enough tension against the cylinder wall to scratch off the oil film which will begin the scoring/seizure process. A piston seized in this way will have heavy scoring around the entire diameter of the piston, with the ring usually locked into the groove all the way around as well.
Lubrication related seizures - By now it's apparent how important the oil film strength can be. Equally important is the amount of oil that is present in the engine. Most watercraft engines carry factory recommendations for oil premix ratios between 40:1 and 50:1. For the rpm's and operating temperatures of a stock engine, these mix ratios work fine. However if your rpm range is significantly raised by aftermarket modifications or bolt on's, you may need to increase your mix ratio slightly.
The total amount of time that it takes for a drop of oil to get from the carburetor, to the lower end bearings, to the top end, and out the exhaust port is called "oil migration time". As peak rpms increase, the amount of time that a drop of oil remains inside the engine is drastically shorter. In other words, a 9000 rpm race engine would need a mix ratio of about 32:1 to maintain the same internal lubrication presence that a stocker would have with a 50:1 mix. There are several oil brands that claim that their oil can provide equal lubrication at a leaner mix ratio (60:1 or 80:1) because of a claimed better lubrication quality. In my 20 years of working on racing motors, I have never experienced this to be true nor has any oil manufacturer, to my knowledge, proven it to be true. It's like running your truck on two quarts of a special oil instead of four quarts of a standard type oil. The quality cannot make up for the quantity...ever.
Fables and untruths: Cold seizure - this is by far the most over used "seizure scapegoat". It some how implies that the rider ran his engine in a way that caused the failure. At least 95% if the "so called" cold seized engines that I've seen have had a very apparent problem elsewhere in the engine that the original technician failed to see. Telling a customer that he cold seized the engine is an easy way for a mechanic to immediately reverse the guilt and the responsibility.
If a freshly bored engine or a high performance engine were started from stone cold, and then run hard at high rpm within 30 seconds of the start up, it could very likely experience a true cold seizure. This happens because the aluminum piston would experience a radically faster rate of expansion in that 30 seconds than the cylinder does. The reason for this difference in expansion rate is two fold.
First and foremost, the internal temperatures that the piston crown is exposed to at full load are on the order of 800°F - 1100°F. The gases passing through the exhaust manifold ports is also in this 800° -1100°F temperature range. The expansion rate caused by these temperatures is usually not a problem when the water entering the exhaust manifold is being preheated by the very hot exhaust port passages. However in the first 30 - 50 seconds of operation, these internal exhaust ports have not yet absorbed the heat that's needed to properly pre heat the cold incoming water. During the first 30 operating seconds, this cold incoming water will briefly maintain the water jacket around the cylinder at "stone cold diameter" while the piston is becoming "full temperature diameter". On engines with properly sized pistons, the difference in these diameters becomes much more than even the best oils can withstand. Any engine that has been warmed up for 60 seconds or longer, would be virtually incapable of a "cold seizure"
Cold water seizure - Like many other people, I have operated stock as well as heavily modified machines in water as cold as 51°F with no seizure or scoring problems of any kind. These are all typical machines that were all originally prepared to operate in 60° - 80° water. It is my opinion that as long as proper warm up is performed, blaming water temperatures down to 51°F for any piston seizure is just another case of scapegoating. I can honestly say that I have absolutely no expectations of ever testing any high output engines in water under 50°F. I would be keenly interested to read an article from any thawed out individual who has.
Hot water seizure - the hottest water I have ever operated high output race machines in is 92°F. These particular machines were equipped with the same single cooling line system that they had used in the 62°F ocean only two days earlier. Both test sessions put these machines (a 550 modified and a 650 modified) through numerous closed course and full throttle radar tests. Subsequent internal engine inspections showed no signs of any piston scoring or seizure what so ever. There was no doubt that the warmer water caused both machines to lose peak speed ability after repeated radar passes. However these losses leveled out after 4 or 5 passes. When the machine was permitted to cool down briefly, the higher peak speeds would return. While this one experience may not necessarily qualify as the gospel for every machine in the nation...It qualifies for me.
Leaning out - this is a term for a phenomenon that doesn't exist. It implies that a carburetor, whose needle/seat and high speed metering screw is properly set, will suddenly begin to meter slightly less fuel to the engine for no apparent reason. This does not happen...ever. In most cases what a rider is actually referring to is the way his machine begins to slow down noticeably during a long full throttle pass. In most cases this slowing is the result of a serious overheating problem caused by excessive compression, ignition advance or poor quality gasoline.
Seizure by running out of gas - as many people already know, a larger size needle and seat must often be installed into a carburetor to contend with the increased fuel demands of a moderately modified engine. If a modified engine is operated at full throttle with a stock size needle and seat, it will usually carry full rpm for about 2 or 3 seconds and then shut off as if someone hit the kill button. When the machine comes to a stop, the rider touches the start button to see what the problem is. The engine, no longer in fuel deficit caused by the undersized needle and seat, unexpectedly starts right up.
This instant high speed shut off is caused by the carburetor literally running out of gas. It is sometimes implied that during this shut down moment of fuel starvation, the engine is also starved of the oil that is pre mixed in. This perceived oil starvation is then blamed for any subsequent piston scoring or seizure. Watercraft pistons do not seize in this way...ever.
At the moment that the fuel starved engine shuts down, combustion and all the heat associated with it "ceases". Unlike a motorcycle whose rear wheel traction continues to move the pistons in the bores at a very high "friction causing" speed, the propeller and pistons in a fuel starved watercraft stop turning almost instantly. The heat and movement friction that can cause seizure are virtually non existent in a fuel starved watercraft shut down. This same concept applies to any machine that simply runs it's main tank dry before having to switch to reserve.
It is possible for a rider, whose carb has an under sized needle and seat, to induce a piston seizure. However this would require a great deal of combined skill and stupidity. Once the rider has established that extended full throttle operation causes his engine to quit, he might make the very poor choice of only applying enough high speed throttle to avoid starving the engine. When he does this, he will be capable of maintaining about 90% throttle which will hold the engine endlessly on the lean thresh hold of fuel starvation. As this rider eventually masters this throttle position, he will be able to maintain a very high rpm with the carb feeding a horrifically lean mixture. Ultimately his finesse will be rewarded by one of the most abrupt and destructive lean mixture seizures that his mechanic has ever seen. _________________ NSR300R - Why did i ever have a 250...
I also am new to this. I have been just letting it sit without any throttle until about 45* then I would ride off. Am I doing it wrong? What temperature should I warm it up to? I do not have a manual and do not know what the operating temp is.
"Just a wild stab in the dark here...........you never cold seized an engine did you?"
Hi there fontyyy,
No I never have.
Having a dad who`s a mechanic, I got it drummed into me about how to treat an engine at an early age, around 6years old.
Bikes like Fizzies, various DT`s, LC`s etc, obviously I wouldn`t ride off until they could run reasonably with the choke off.
All I`m saying is there`s a difference to genlty riding until the engine is up to full operating temp as opposed to screaming the tits off it from cold.
I quite happily ride off after a few mins`, rather than spend 10-15 mins sitting there blipping the throttle.
Obviously I take it easy until it`s up to temp.
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