reg/rect Cooling

[Guest]

I was web hopping found this interesting article. Using computer fan to cool rec/reg https://www.geocities.com/motorcity/.../reg-rect.html
on the sportbike network

[Anonymous]

That's not actually a bad idea. Heat is hard on electronics, and these little CPU fans run on 12 Volts. You can tap them into just about anywhere. Hey, at $120 for a recitfier, and maybe $10 for a fan, I'm going to give it a whirl. Heck, I may even see what temp readings I get.

Roger

[Anonymous]

Very interesting! I had heard/read somewhere that another option is to transfer the R/R unit to the front of the bike where airflow is better.

[Anonymous]

Now that's cool.

[1100ED]

of all the crazy ideas---


Well actually i just purchased a small cooling fan used for cooling microprocessors and have its installation on my to do list. Now i am thinking of cutting small pieces of a heat sink and epoxying them to the rectifier if it doesnt look too ugly. What do you think of the epoxy and extra heat sink idea???

[Anonymous]

I don't think epoxy is going to do the trick of efficiently transfering the heat to the sinks. You might be better off using a dialetric grease (such as the stuff sold for use with processor cooling fans) and semi-adhering extra sinks to the R/R with that. Further thought on this matter tells me that it might be possible to rig up a clip (again, like a computer's CPU) to hold this assemble tight against the R/R. Personally if heat is an issue, you might be better off rerouting some air flow across the R/R with a homemade ram.

[earlfor]

Tony
For additional heat sink material to function, there must be good metal to metal contact. A layer of epoxy used to glue the extra material in place will act as an insulator and be self defeating.
If I felt that I needed to increase the cooling fin area, I would carefully drill 1/8" mounting holes through the fins and mount extra fins with 8/32 nuts and bolts.

Earl

of all the crazy ideas---


Well actually i just purchased a small cooling fan used for cooling microprocessors and have its installation on my to do list. Now i am thinking of cutting small pieces of a heat sink and epoxying them to the rectifier if it doesnt look too ugly. What do you think of the epoxy and extra heat sink idea???

[Anonymous]

Move it!

The rectifier gets hotter the more work it has. More work=higher rpm=higher speed=more wind. I don't think a computer fan would do any big difference compared to the wind when driving. Move the regulator instead if you're worried.

Now for the electronic engineers reading:
Are the replacement regulators switched or regular? If they we're switched, they wouldn't absorb much energy at all. Someone who knows?

/ Henrik

[gsman]

Re: Move it!

The rectifier gets hotter the more work it has. More work=higher rpm=higher speed=more wind. I don't think a computer fan would do any big difference compared to the wind when driving. Move the regulator instead if you're worried.

Now for the electronic engineers reading:
Are the replacement regulators switched or regular? If they we're switched, they wouldn't absorb much energy at all. Someone who knows?

/ Henrik

My recti. is behind my left hand side panel so there is not much wind gonna hit it... an Electrix recti. is noticibly larger with larger fins than stock. harley puts theirs right in front of thr motor for cooling

[Anonymous]

Now for the electronic engineers reading:
Are the replacement regulators switched or regular? If they we're switched, they wouldn't absorb much energy at all. Someone who knows?

Henrik, what exactly do you mean by switched? I think they are just a series of transistors and diodes. I doubt Electrex does it much different. Just probably provides better components and cooling.

As for the cooling fan, I think there was significant proof in the original test series to prove that the cooling fan helped. We make a lot of different devices here where I work, and you'd be amazed how much just replacing ambient air surrounding a device can help. And remember... you bike isn't always moving while it's running, and this is when the temp increase can get high. Any chance to keep it from EVER getting hot will prolong its life.

One thing you could try that I just thought of... mount the reg/rec to a set of stand-offs to provide cooling across the back of it too (as much as the side cover allows anyway. It may be that the side panel is a type of heat-sink too, so don't do this without taking temp measurements.

Cheers,

Roger

[Anonymous]

Tony
For additional heat sink material to function, there must be good metal to metal contact. A layer of epoxy used to glue the extra material in place will act as an insulator and be self defeating.
If I felt that I needed to increase the cooling fin area, I would carefully drill 1/8" mounting holes through the fins and mount extra fins with 8/32 nuts and bolts.

Earl

of all the crazy ideas---


Well actually i just purchased a small cooling fan used for cooling microprocessors and have its installation on my to do list. Now i am thinking of cutting small pieces of a heat sink and epoxying them to the rectifier if it doesnt look too ugly. What do you think of the epoxy and extra heat sink idea???

I also have a small computer fan and will not use epoxy but will use screws as you suggest. I was also thinking of bolting some small heat sinks to a couple of the existing regulator finns

[Anonymous]

Heat sink stuff

As an avid PC cooler junkie, I know all sorts of tricks for cooling PC's.

As far as epoxy, they do make a heat sink glue, that will permenantly (more or less) glue a heat sink to what ever you stick it too.

I too have toyed with the idea of gluing extra heat sinks and other accesories to my R/R, but I could never find a place on the R/R that a heat sink would make enough contact with to be usefull. Considering that the R/R's are allready housed within a heat sink, i feel the best solution is to relocate them to the front of the bike, or I've noticed alot of people choose to put them behind the passanger footpegs for better airflow, and to avoid dripping acid from the battery.

Just my 2 cents

[lecroy]

of all the crazy ideas---
What do you think of the epoxy and extra heat sink idea???

Not so crazy. More surface area, the lower the sink to air thermal resistance. Get a small tube of Silicone heat sink compound from the local electronics shop. Be care not to get any on you or your clothes. Mix it into your epoxy at about 10%. Make sure it's well mixed. Make sure the sink you plan to add fits good to the other surface and that the surfaces are free from oils and greese.

I don't like the fan idea because it's one more thing to fail. Normally when I ride, I am not sitting with the engine running, BSing. I am instead following granny, which is not much faster. This is where the air flow comes from to cool the electronics. If you do not have a good source of air while the bike is moving, you may want to consider making a duct to force the flow across the fins.

On my HD, they were smart enough to put the electronics in the front of the engine.

[Anonymous]

Maybe a little air scoop on the side of the cover would do it without any real fancy work being necessary

[saaz]

Without the standard air box in I think more air gets through. My regulator went about 20 years ago, no trouble since (early GSs had separate regulator and rectifiers)