Electric Plenum Heater Take 2

[skiri251]

who444444 » Mon Feb 17, 2014 7:00 pm[/url]":1cmzr9gq]
Positive in and negative out?

Yes.
Positive comes from headlight power (out of relay I installed) and negative goes to the frame ground.

 

[joedrum]

hmmmmmm so this is like dumping excess stator output to frame or dose this do different coming from headlight lead.....seems to me if the regulator dumps excess to frame this is where the plenum heat power should come from ? :headscratch:

 

[slabghost]

Moving the regulator to dump heat at the plenum may or may not be enough depending on the load.

 

[skiri251]

Moving the regulator, I see.

Well as I understand it (heard somewhere in CGW), if Oldwing charging system always generates fixed amount of power and dumps unused excess as heat @ the regulator, then hooking up this heater resister uses up some of them so the end result should be less power dump at the regulator.

 

[joedrum]

hmmmmm ...just trying to figure out how to get it all .. without any chance of loading up stator in any way pass its output

 

[AApple]

Definitely "outside of the box" thinking! :good:
But....ya'll know me...I gotta play devil's advocate here...
What happens if that thing shorts out, or a terminal gets broken for some reason? From what I've heard, having large sparks taking place inside the manifold ain't such a good thing.

Again...it's a neat idea, and if it does the job, it's a heck of a lot easier/quicker than figuring out some other way to heat the manifold with coolant...and a dang site cheaper, too! I just gotta throw in the "what ifs"....it's my nature. :mrgreen: :hihihi:

 

[sgq700]

How about just bolting the volt reg to the floor of the intake ? They stay really hot all the time don't they?

 

[skiri251]

AApple » Tue Feb 18, 2014 11:08 am[/url]":1wrovd1b]
Definitely "outside of the box" thinking! :good:
But....ya'll know me...I gotta play devil's advocate here...
What happens if that thing shorts out, or a terminal gets broken for some reason? From what I've heard, having large sparks taking place inside the manifold ain't such a good thing.

Again...it's a neat idea, and if it does the job, it's a heck of a lot easier/quicker than figuring out some other way to heat the manifold with coolant...and a dang site cheaper, too! I just gotta throw in the "what ifs"....it's my nature. :mrgreen: :hihihi:

Yes. I thought about that too.
That's why I put fuel line over the wires to avoid short. Open circuit failure is fine but short must be avoided.
JB Weld to plug the gap also acts as protector. Wire insulation cannot be worn down by the plenum hole edge.
The resister looks sturdy enough. It's basically a piece of metal.
Anything beyond that, you need to start worrying about a lot of other what ifs for this 30 year old motorcycle. :hihihi:

 

[skiri251]

sgq700 » Tue Feb 18, 2014 11:25 am[/url]":1z3baiwy]
How about just bolting the volt reg to the floor of the intake ? They stay really hot all the time don't they?

If it is hot, then it certainly helps.

 

[ekvh]

The time you need it most is early startup. This is where the regulator is probably dumping the least as it is trying to bring the battery back to its charge level. The battery would be low from starting the bike. Then it would depend on what else you're running. A switch to turn the headlight off while warming up might help.

It's too cold here to try, but someone should fire one up cold and see how hot they get.

 

[skiri251]

joedrum » Tue Feb 18, 2014 10:51 am[/url]":15iil065]
hmmmmm ...just trying to figure out how to get it all .. without any chance of loading up stator in any way pass its output

For this, I think we need field coil type of alternator. My '78 XS750 got one. The regulator regulates field coil current to adjust the magnetic field strength thus output AC.

 

[skiri251]

ekvh » Tue Feb 18, 2014 11:53 am[/url]":1miod7pz]
The time you need it most is early startup. This is where the regulator is probably dumping the least as it is trying to bring the battery back to its charge level. The battery would be low from starting the bike. Then it would depend on what else you're running. A switch to turn the headlight off while warming up might help.

It's too cold here to try, but someone should fire one up cold and see how hot they get.

I will test it today.

 

[dan filipi]

AApple » Tue Feb 18, 2014 10:08 am[/url]"80p93tw]
Definitely "outside of the box" thinking! :good:
But....ya'll know me...I gotta play devil's advocate here...
What happens if that thing shorts out, or a terminal gets broken for some reason? From what I've heard, having large sparks taking place inside the manifold ain't such a good thing.

Again...it's a neat idea, and if it does the job, it's a heck of a lot easier/quicker than figuring out some other way to heat the manifold with coolant...and a dang site cheaper, too! I just gotta throw in the "what ifs"....it's my nature. :mrgreen: :hihihi:

Even if there is a spark and the mix is ignited, the flame will get sucked in just like a carb backfire.

 

[skiri251]

Just came back from the test ride.

Ambient was 55F to 60F.

First impression out of the drive way was not so great. I mean I was expecting more low end torque but I couldn't feel the difference.
Around the neighborhood plenum temp was mid 80s I think. I didn't feel anything strange so decided to go to usual mini-twisty followed by seaside straight route, 30 miles of total riding.
Up climbing the twisty I turned off the heater expecting the temp to drop. To my surprise it was hovering around 70F.
I started liking the smooth engine response especially from 3K to 5K rpm.
Into the seaside straight I rev'ed it to 7K rpm then saw immediate drop in the temp down to low 60s so I turned on the heater again.
Going around 3K rpm, the temp slowly came up again to low 70s.
Then I opened up to 7K again and another drop to low 60s. I kept it around 5K and the temp went slightly below 60F.
On the way home in the city street, the temp came back to 80F again.
I touched the runners with bare hand and it was fairly warm around 100F I think.

So far, I am satisfied with the conversion. If I can feel the low end umf, it's even better. Could it be that I have 1.5" ID runners?
Should I try choking them?
Also I guess the next question will be what happens on a freeway with sustained 5K~6K running. Maybe I should add one more resister. With high rpm, I think I can afford extra 70 watt.

 

[skiri251]

skiri251 » Tue Feb 18, 2014 11:55 am[/url]":29f27omh]

ekvh » Tue Feb 18, 2014 11:53 am[/url]":29f27omh]
The time you need it most is early startup. This is where the regulator is probably dumping the least as it is trying to bring the battery back to its charge level. The battery would be low from starting the bike. Then it would depend on what else you're running. A switch to turn the headlight off while warming up might help.

It's too cold here to try, but someone should fire one up cold and see how hot they get.

I will test it today.

Okay, I touched it with my bare hand while I was adjusting the idle mixture.
I could touch it for 10 seconds or so before I felt the burn. So maybe it's 110F~120F?
It will definitely help if I can mount it under the plenum but mine is V shape and the regulator is too big.

 

[joedrum]

hmmmm so your thinking you have increased cooling needs at higher rpm ..seems logical ...it also is logical that higher the rpm the less available power there is ....I wonder if two resistors will dim the headlight some the way its hook up ... hmmmm this is neat to follow

 

[skiri251]

Update.

Added one more resister and painted the intake.

Two resisters can be turned on independently.

As for the runners, I added 4" long 1.06" ID pipes to better mimic Dan's setup.

Just came back from the usual route.
I think it got better. My senses are influenced by the weather and how I feel and today is definitely better day than the other day weather-wise so I am not 100% certain but pretty much. :hihihi:

Ambient was from 65 to 70F.

The low end drivability improved. Before it's 3000 rpm and up but now from 2500 rpm. This is 5th gear and slight uphill.

I got low end bog twice when engine was cold (plenum temp around 60F). It disappeared as the engine warmed up.
With two resisters on, it was quick to climb to 100F. It was still climbing so I turned one resister off.
With today's weather plenum temp was constantly around 100F. I touched the runner again and it was warm so this number is not only plenum close to the resister but overall.

So I think I am satisfied and call it completed.

 

[dan filipi]

I would fill and seal the space around the reducers and bevel the inside edges.
This way full flow would go through the smaller pipe.

 

[skiri251]

dan filipi » Sun Feb 23, 2014 4:05 pm[/url]":27ytwzuj]
I would fill and seal the space around the reducers and bevel the inside edges.
This way full flow would go through the smaller pipe.

There are transition pieces on the other end so the flow should only go through the smaller pipe as they are.

BTW, I have no idea what kind of jetting it has now but the plugs look okay (tan to white).
I guess the next step is to look at the MPG.

 

[who444444]

sounds like you have a good working system.congratulations, enjoy the ride. :clapping:
dave