Engine warm up time.

[SULTAN]

Good day to one and all,

I ride a 2001 Fjr 1300 with a 4 into 1 exhaust. (Bought like that.)

This may be a stupid question, but ia there any way of reducing the engine warm up time. I timed the bike in the morning and it took 2,5 minutes to get down to idle.

I tried riding the bike before it was on idle and when de-accelerating there was a large amount of backfiring.

In the service manual they state that the warm up period is controlled by water temperature.

Here in South Africa, it does not get that very cold at all. I am all for warming up the engine but i find that 2,5 minutes is a bit long.

My two previous bikes were a Honda Blackbird and a Honda Valkyrie, and niether needed that amount of time to warm up.

Are there any modifications out there.

Any help or suggestions would be greatly appreciated.

Safe riding

SULTAN

 

[ionbeam]

You can ride away immediately after starting the engine. I understand that you hear lots of backfiring, this is OK and normal. The FJR has an Exhaust Air Injection system that is active until the thermostat opens. It injects air into the exhaust, right at the exhaust valves in the cylinder head. When the air meets rich exhaust there is a secondary burn that you hear as backfiring. You can really provoke the air injection to cause backfiring by accelerating then chopping off the throttle in first and second gear. Since there is no harm, just annoyance from the noise, ignore it and ride off. The engine should run just fine when cold. There is a chance that your 4-1 exhaust system exacerbates cylinder scavenging making the backfiring worse than on a stock FJR.

There is a work-around for this, I won't call it a fix because nothing is broken. Forum member 08FJR4ME (Dave) makes a blank-off plate set for the reed valves that induct the air into the exhaust. This lets you remove all the Air Injection plumbing and the huge solenoid over the cylinder head cover. This is completely safe and no risk. You can read about the plates and see order information here, click on the picture of the blank-off plates:

 

[Bounce]

Also consider that nothing is free. If you could get the coolant temp up high enough to reduce warm up time, there's a good chance it wouldn't cool down as quickly as it does now, so it would probably run hotter when riding it (not good for the engine).

As for backfiring, ease off the throttle instead of chopping it completely closed and see if that reduces the air injection "contribution".

 

[wfooshee]

The backfiring is by design, not a fault of the engine. When it's cold it mixes air into the exhaust so that unburned hydrocarbons burn in the exhaust rather than being dumped into the air. That's the popping sound. It's for emmissions control.

Ride away as soon as the bike starts. Sitting and "warming up" is a waste of good fuel.

The bike will warm up faster as it's being ridden, rather than just sitting at idle, too.

The fast idle is controlled by an assembly under the fuel rail that holds the throttle plates slightly open. That takes the place of a choke on a carbureted bike. When it gets warm, that assembly stops functioning and the throttle plates close fully to regualr idle settings.

 

[SULTAN]

Thank you all for replying. ionbeam, thanks for the links from the picture. I understand the situation clearly now.

Once again thanks.

Safe riding

SULTAN