What's really going on with Yamaha handlebar warmers

[Bradford]

I've been reading a lot of threads to get a better idea of how to get hotter hands. My 06 Nytro has the 08 bar update but like so many others, there are nights when a bit more heat would be nice.

The following information is based on my 06 Nytro. I can only assume it applies to other models...

I borrowed a scope and hooked it to the heater circuit. What I found is the variable heat settings are a function of a PWM (pulse width modulation). You can see this in this pic from gade-thrasher: http://www.ty4stroke.com/viewtopic.php? ... e&start=60

This pic of the PWM pulses show a duty cycle (or % output) of about 30% on low and 50% on high. This led me to think that the high setting only gives 50% of the available heat. What I found is the engine RPM plays a roll as well. Basically:

- Below 1100 RPM, the heaters are off regardless of the heat setting
- Between 1100 RPM and 4000 RPM, the heat setting and the engine speed effect the heat output
- Above 4000 RPM only the heat setting has an effect on the heat output

I ran 4 different tests to gauge the heat output under different situations. Here's what I found:

1. Below 1100RPM, the heaters are always off, regardless of the setting

2. At 1100 RPM, the heaters are always at 30% regardless of the heat setting above 0 bars (0 bars is always off)

3. At 4000 RPM, the heat output is a function of the number of bars as follows:
- 0 Bars = 0%
- 1 Bar = 30%
- 2 Bars = 40%
- 3 Bars = 50%
- 4 Bars = 60%
- 5 Bars = 70%
- 6 Bars = 80%
- 7 Bars = 90%
- 8 Bars = 100%

4. With the heat set up full, the heat output is a function of engine speed as follows:
- 1100 RPM = 30%
- 1800 RPM = 40%
- 2300 RPM = 50%
- 2600 RPM = 60%
- 3100 RPM = 70%
- 3400 RPM = 80%
- 3700 RPM = 90%
- 4000 RPM = 100%

As you can see, full heat is available when the heat setting is at 8 bars and the engine is at or above 4000 RPM. This explains why my hands do warm up after riding for a while. What I can't figure out is why Yamaha would vary the heat output at low revs and turn the heaters off below 1100 RPM. Maybe the magneto only has enough output to feed the lights and battery charging circuit at the lower engine speeds??

Brad

 

[cannondale27]

That makes sense.But it still doesnt explain why some are hotter than others.Over in Phazer section there is a real hit and miss thing for whos are hot and whos arent.Those that are hot like mine get hot even at idle.Maybe the good ones are actually defective.

 

[Bradford]

That makes sense.But it still doesnt explain why some are hotter than others.Over in Phazer section there is a real hit and miss thing for whos are hot and whos arent.Those that are hot like mine get hot even at idle.Maybe the good ones are actually defective.

Darn.... foiled again!

Maybe that explains why some people can't figure out why other people are complaining about cold hands

 

[cannondale27]

Yes I think thats the case.Is very frustrating to those with the issue.I wonder if they sourced stators from different manufacturers?

 

[SRXSRULE]

A huge part of how well the grips work for each person is what kind of riding they do, how warm there gloves are and how big of windshield they have on.

I trail cruiser with good gloves and a mid size shield is very likely to have no problem with them. Me on the other hand---- I ride a mountain sled with a huge riser, almost no windshield and always on and off the throttle and my hands froze!

What I did on my sled was run two sets of warmers. I took the 06 bars, removed the hooks and knocked out the threaded inserts inside the bars then installed heaters inside the bars. Welded the threaded insert back in, put the hook back on and had smokin hot hands anytime I wanted to. Turn both sets on high and I could dry wet gloves Eric