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Hi Guys,

I get my bike delivered today and I'm wondering how long does it take to warm up before you can jump on and ride? I've owned small trail bikes in the past and I never let them warm up. Is it bad not to warm up, or is it just suseptible to stalling if you don't?

Thanks :)
 

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You can go right away, but that's not the best way to do it. Running a cold engine too hard is one of the leading causes of engine failure. I have had several bikes with warnings stating to thoroughly warm up the engine. They had FI too. My Vespa 300 still has this warning on it. After much reading about the subject, the concensus seems to be to start it, let it idle a minute or two while you get your gear on, check air pressure, or whatever, then take off slowly and keep the rpms at 2000 or so for an additional 5 min. Then, you can ride it harder. If your outside temp is like 30 F, I would let it warm up more like 5 min. I never ride my bikes hard until they are HOT. This takes at least 7 minutes from the first startup of the day in moderate outside temps.
 

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Its FI. Start it up and go
This has to be a joke I'm just not getting right?

Fuel injection has nothing to do with the need to warm up the engine.

The point of letting the bike warm up is that the oil reaches maximum viscosity at higher temps. Running your bike with cold oil means you'll have less lubrication for the internal components. Not good!

It is pretty common that most people who live where temps go below 50 at night and never let their car or motorcycle warm up end up having head gasket and other engine related issues because of it.
 

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This has to be a joke I'm just not getting right?

Fuel injection has nothing to do with the need to warm up the engine.
Umm, no, it is very real...FI allows you to ride away after a very short warm up period without worry.

You'll notice that in cold conditions, when you start your bike, it will have a higher than usual idle speed until it warms up. Additionally you'll notice the bike will maintain that idle without intervention. This is because fuel injection gives the engine a richer fuel to air ratio when it is cold, and modifies the idle rpm to compensate as well. These are things you would need to do manually on a carburetor bike.

Granted, you still need to let it circulate fluids for about a minute, but thats it. FI takes care of the rest. Just don't rip it off the line before it really comes up to temp. The engine will be able to handle moderate driving until it is completely up to temp just fine.
 

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Every FI bike I have owned I have started up and gone..

My warm up consists up starting the bike, then putting on gloves, helmet, and jacket.. Then I am gone.. Done it for years and thousands of miles without a single problem, including morning with freezing temps..

Now with carbed bikes I would let them run for 5+ minutes in the cold before attempting to get on it..

Just what I do, not saying its right or wrong..
 

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Every FI bike I have owned I have started up and gone..

My warm up consists up starting the bike, then putting on gloves, helmet, and jacket.. Then I am gone.. Done it for years and thousands of miles without a single problem, including morning with freezing temps..

Now with carbed bikes I would let them run for 5+ minutes in the cold before attempting to get on it..

Just what I do, not saying its right or wrong..

Ditto on both points. Still funny to see one of our staff when he rides his vintage bikes ( pre 79 Kawi, Yami or Suzi) and they each seem to take about 10 minutes to warm and be ready to ride.




.
 

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Keep the rpms at about 2000 for about 5 minutes? Not on this bike, you'll be shifting every half second and top out at like 20 mph. :D

Sent from my SCH-I510 using Motorcycle.com Free App
 

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I usually let it warm up as im putting my gear on and getting situated, about 5-10 minutes.
 

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Umm, no, it is very real...FI allows you to ride away after a very short warm up period without worry.

You'll notice that in cold conditions, when you start your bike, it will have a higher than usual idle speed until it warms up. Additionally you'll notice the bike will maintain that idle without intervention. This is because fuel injection gives the engine a richer fuel to air ratio when it is cold, and modifies the idle rpm to compensate as well. These are things you would need to do manually on a carburetor bike.

Granted, you still need to let it circulate fluids for about a minute, but thats it. FI takes care of the rest. Just don't rip it off the line before it really comes up to temp. The engine will be able to handle moderate driving until it is completely up to temp just fine.
I would give it about 2-3 minutes. Enough time to basically put your gear on. Will give it enough time to warm up a tiny bit, but also make sure the oil has fully coated the transmission. Unlike a car, we don't have a dry clutch, so immediately starting and driving off could cause a lot of extra wear on the clutch. Cold oil is thicker and will kill some of your power output until it warms up a bit as well as you lose a bit of power from the relatively cold combustion chamber since fuel isn't atomizing efficiently. Just enough time to get your helmet, gloves, and jacket on (you should already be wearing pants and boots I hope.)
 

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So the fuel injector does the job of a choke basically, I get that. What I don't get is how that equates to the oil reaching "safe" operating temps in a fraction of the time it takes on a carb'd bike. 2000RPMs is the same no matter FI or Carb.

I start a cold carb'd bike applying the choke and it idles at 2.5k RPM for 8 minutes then idles down. I disengage the choke and let it idle for another 2 minutes and the needle is almost half way between the C and H which represent hot and cold.

My question is, how does fuel injection warm the oil up in to safe operating temps in 2 minutes at the same 2.5k RPMs?

Same oil, same engine, same weather, same RPMs, but you all are saying FI reduces warm up times by at least 80%.

Can anybody explain this to me? Is the gas burning at a hotter temp than with a carb?

I can be wrong, no issue there but I at least want to learn from being wrong.
 

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It's not for the oil reaching the proper temperature. If you are using the proper oil for the temperature you're in, your oil is already at a functioning viscosity to be used. It's only a little thicker than normal but well within operational use unless you are subzero temps and aren't using the proper oil. The reason you gotta let a carb bike warm up more is that the carb cannot adjust for the inefficiencies of combustion in a cold engine. It just allows you to up it's fuel by a set% via the choke which cannot compensate very well when you give it more and more throttle. Hence why on a cold carbed bike even with the choke on, if you try to get on it with the throttle it'll just stall. An FI bike overcomes this by just adding more fuel as needed and can adjust on the fly to throttle inputs. A little loss of power vs fuel pumped in due to a cool combustion chamber, but it can compensate by just adding more fuel as needed. The carb can't. My cruiser is carbureted and I only warm it up a few minutes. I'll start it on full choke, and immediately retard it to about half choke once started. Then just let it idle while I'm putting my gear on and opening the gate and by the time I do all that I just ride it out of the gate, close the gate and after I get down a block or so, turn the choke all the way off and the engine is self sustaining at that point. Total warm up time at most, 5 minutes.
 

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I give it about a 2 min to warm up. It list in the book failure to let the engine warm up after starting can lead to a engine seizing. I know the tell you with the old 250 to start it and go right away to keep the valves from caking up. But you really need to keep it under 4k.
 
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