I was reading something about EFI and the mapping that you need to learn about. The book I was reading said warm-ups were a thing of the past. I know my fathers Harley fires right up and away he goes.
So, I thought "what is it about my carb'd machine that requires it to warm up before it will run correctly?"

 

its my opinion and experience that ANY bike can be tuned well enough that it can start easy and take right off sputter free with zero warm up time, regardless of weather, including extreme winter. unfortunately it seems few quads are tuned that well. it is difficult for most to get that kind of tweek. with EFI there are no hassles with this, the sensors and computer take care of it for you. and then there is the issue of climate and altitude changes that necesitate retweeking to maintain performance, and again EFI takes care of it for you too. if you travel lots, especially to the West, and visit high altitudes frequently, or go from hot to cold thru the course of a ride trip, EFI cannot be beat for hassle free maintaining of peek performance.

however, I feel warm up time prior to riding is a good thing to practice, regardless of how well the carb is tuned, or if EFI is being used. I prefer allowing thermal expansion of the cylinder and piston and all that jazz to take place at an easy pace, rather than force it by sitting there reving like crazy, or riding ***** to the wall right off the bat.

 

I think "WARM-UPs" on any motor is critical for good oil flow to ALL parts of the motor

On ALL the older H-D (evo and older) Warm-up is a must..........I've seen allot of people start and ride right off the bat. Then they wonder why they have to pay $2000.00 for base gasket replacement.........

The "Twin Cam" motors are not as critical for full warm-up BUT they too have had problems with base O-Ring oil leaks.

Motor warm-up IMO should be done regardless of WHO SAYS it won't hurt your motor...........[img]i/expressions/face-icon-small-smile.gif[/img]

 

Statistically the most common cause of internal damage comes from running hard with insufficient warm up. I start putting mine under load at about 150 degree's water temp.

 

I warm my things up before running, but how many of you know people that get in their cars and go. In the old days you HAD to let your car warm up! LOL! They were all pre- EFI. God I sound old.
I just didn't know what it was exactly that needed to be warmed up to make the machine run at optimum. My dad says you are right. All that jazz being different types of pressures the the engine goes through during warm-up and running/operating temp. The sensors in the EFI control fuel flow in changing conditions. My pop says his Harley will richen up at a light to run more fuel through, thus cooling her down.
The carb is set to run at optimum when hotter.

 

I agree as I have stated about warm-up being important, but I do think the EFI sales pitch is aimed at carb related issues that require extensive warm-up. many an ill-tuned and mal-adjusted carb out there won't let the bike run well at all until full operating temp is reached above 180 degrees. and for guys running utility quads for work in the woods or on the farm, going from fence post to fence post and the like, in the middle of winter at zero degrees, are battling their engine going from operating temp to totally cold in a matter of minutes in the cold wind while they take care of one simple task after another. spending more time waiting for the motor to warm and quit sputtering than they are spending mildly cruising from one place to the next at a casual pace with no hard riding in mind. I think this is one reason why so many utility quads have EFI, and sport bike's are a step behind them with it.

 

Good topic gang - I agree 100% on the warm ups. It's kinda like when your trying to have fun with your wife, you have to warm her up, no jumping right in with that situation!

 

LMFAO... Nice analogy BlackHawk[img]i/expressions/face-icon-small-happy.gif[/img]... and so very true... if you don't warm that one up you'll blow a seal for sure, and then you're in big trouble.LOL

 

Several things. A carb dumps fuel into the intake which is cold. This cold metal will cause the fuel to condense on the surface. That will cause the engine to go lean. An EFI shoots the fuel right at the intake valve head so the fuel does not stick to the intake tract.
Another problem is when air is cold it contains a lot of O2. This will cause the motor to go lean too. An EFI is mapped so when the temp sensor says it's cold out, it will inrich the mix. Same way with a carb but you do it with your hand on the choke ****.
Some really good EFI systems won't let you go WOT until the engine reaches a certain temp. This is a way good feature!!!! I had to chew out the driver of the race car the other day. He lit the thing off and proceeded to rack the throttle. He knew better and I let him know what I thought of his little antics. Ha ha ha ha...........he could not hear me because of the engine running..............but he "knew" what i was telling him!!!!!!!!!

 

an EFI doesn't need a normal warmed-up like a carb has to be,but as any engines the cooling system must run
a little while to avoid too quick heat transition to motor and to keep a consistant temp in the long end.