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Discussion Starter · #1 ·
Im about to try to install the Ducati fan I got, but I may have a bit of an issue with space behind the rad. Does anyone know how much more forward the rad can be "pushed" comfortably. It looks like I may have to lop some of the cam shaft off, but can only go so far before I reach the oil seal on the tach housing.



This is the one I have









The "depth" of the entire fan is about 2.3" and I am wondering if that is just too deep to use and should get another one, or if I can make it fit with a little tweeking. Im hoping someone here can give me an idea of the "depth" of fans they successfully installed.
 

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I only had to take about 3 mm off the Cam shaft end.On my first conversion I brazed an extra nut on the right hand side next to the bottom arm hole to move the rad forward but later decided I'd never go back to a Mech fan so lopped off the Cam-shaft end.As per my pages you can still retro-fit a Mech fan using washers inside the rear of the hub of a Mech fan if you so wished.



http://globalcxglvtwins.hostingdelivered.com/viewtopic.php?f=7&t=209



http://globalcxglvtwins.hostingdelivered.com/viewtopic.php?f=7&t=557



If you fix the fan as per my pictures it is off-set and the Cam shaft end will sit inside the recess of the fan engine but the cam shaft still needs to be trimmed.



The Ducati fans are amazingly efficient and only draw 2 amps.
 

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Discussion Starter · #3 ·
Great info Shep, and now it gives me an idea of where to mount the fan (not exactly in the middle). It looks like from the picture your fan is the same as mine, so I am a happy camper now
Going to lop off the cam shaft just before it hits the tach housing oil seal, as that will give me the max clearance as I will never put a mech fan back on (had the bolt come out and shoot through the rad once lol). Now I can start on this while I wait for the last bit to put the rear cover on, the oil seal
 

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Great info Shep, and now it gives me an idea of where to mount the fan (not exactly in the middle). It looks like from the picture your fan is the same as mine, so I am a happy camper now
Going to lop off the cam shaft just before it hits the tach housing oil seal, as that will give me the max clearance as I will never put a mech fan back on (had the bolt come out and shoot through the rad once lol). Now I can start on this while I wait for the last bit to put the rear cover on, the oil seal


One of the other posters had a proper machine job done and blanked the Cam shaft/Tach end like Honda did on the later 650s.A bit OTT for me






Both my conversions are still running nice with zero problems after several years and many thousands of mile on them.



Note:When you come to do some work later on down the line that requires access to the front of the engine you will get a very smug feeling knowing how easy it is to get to the front engine cover to say clean the sump and check the oil pump and NO Mech fan to remove or Fan Guard!




PS

I just put a new Tach cable on.Real easy with the Rad off
 

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Discussion Starter · #5 ·
Well, time to play with the electric fan. I tried dry fitting the rad with the new fan just tucked behind it (free floating) to see where would be the best place plus how much (if any) I would have to shave off the end of the cam shaft. Found that I could get away with about 3-4 mm as others have done on thier installs, but being one for good clearance I decided to lop about 1/2" off the end of the shaft (about 13mm for the metric guys). Now, I can mount the fan ANYWHERE on the rad with no possibiltiy of interference at all and lots of clearance (as the rad does flex a bit on the rubber mounts). Below is a pic I shot with the cut off bit tape back on to give an idea of how much I lopped off. Even with this much off, there is still a lot of thread hole depth (not that I will ever put a manual fan back on).









I cut the bit off with my small angle grinder and a cut off disc, and was surprised just how soft the cam shaft is, it was like cutting through aluminum, go figure ?







You can see in the pic above where I "filled in" the tach cable hole to make sure I dont get any oil leaks. since my cam worm teeth were screwed up, I will not be able to use the mech tach (not that it ever worked), but since Im almost done my new digital tach (guts stuffed inside original guage housings) it wasnt needed anyway.
 

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I put an aftermarket electric fan on my GL500 that I picked up for about $10 used from a local shop. It's been a year or so (and still works great)so I don't remember for sure the measurements, but I didn't have to take anything off of the cam. It was small enough to sit all the way down and to one side and the cam end sits just beside the fan motor housing as referenced by Shep. I just wired up a switch on the fairing and if I'm sitting in traffic on a hot day I might have to flip it on, usually if I'm rolling it stays cool anyway. And I left the shroud off also.



Of course this info does no one any good because I have no idea what kind of bike it came off of. But there is a fan out there, or was a fan out there, small enough to fit with no grinding on the cam. I suppose if you are motivated enough to retrofit an electric fan it doesn't take that much more to grind a little off of the cam. Just my two cents.



Fib
 

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Thats about as much as I sawed off

when fitting my Zx6R fan

I didnt need to, its just that I wanted more clearance

for a project I have in the offing

Shep kindly sent me 2 75C thermo switches I have one on the bottom of the

rad and it works well but I find it comes on a wee bit early so will bung an 80 in some time.

No rush, its not that vital, better sooner than later

heres the fan and switch fitted to the rad

 

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Discussion Starter · #9 ·
Yea, I could have actually stuck mine in a corner and would have cleared, but decided i wanted it a bit more centered so lopping the cam was problem. I just finished whipping up a small bracket to mount a switch on the bike for manual fan control (plus an LED so I can see when the fan is on). Figuered the best place was where I could reach the switch easy and see the light, so made the bracket to fit under the choke assembly. This way, it goes on easy and I can remove it easy just by loosening the choke nut. Have it primed and decided to snap a pick of it. Already sprayed it with black engine enamel, and sticking it in the over for 2 hours at 300 lol (wife is at work, have to remember to remove it this time lol)









Fianlly got the fan mounted on the rad and im happy. Found some spring nut things and they worked out well, going to gleu them on to the rad housing and then only two screws to hold on the fan (yea, i know, phillips lol all I had that short). Also sprayed the long black bracket with black and mounted it to the fan using locktight. Once I get my temp themostats in I can mount it to the rad and wire it up :) Used a small recessed head screw, and using a larger washer thightened up the screw and indented the fan housing so the screw now sits almost flush inside and well clear of the blades. You can see my JBWeld fix on the bottom of the rad (at the top of pic) where the evil mechanical fan bolt shot through last year when I was 100+ miles from home. Not a pretty feild repair, but it is solid and still leaves the hit core in operation.





 

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Discussion Starter · #10 ·
Nice pics Reg (you must have posted when I was writing mine above). Now, that posses the question to me, where to put the themostat switch, TOP or Bottom of the rad. Seems people are using both and Im not too sure which would be best. On the top it would see the hot coming from the engine, on the bottom it would see what the rad has so far cooled it to. Maybe I will put 2 on lol a 75 bottom and a 80 top ??



So, what does everone figure TOP or BOTTOM My temp units are not here yeat so I can do either
 

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When I came up with the Temp sensor usage I decided on the top for ease of wiring when removing the Rad.It has worked well.You an vary when the Fan kicks in a little by how much coolant you have in the Rad.If you fill to the top the fan kicks in around the middle mark of the temp gauge with a 75 Deg C N/O but sometimes takes longer to kick out.

I have run mine about half to an inch below the neck of the Rad and the fan kicks in and out better.

To be honest there's some leighway because as soon as move from a stop you get air-cooling and the fans soon shut off reasonably soon unless it's a warm ambient temp day and you are doing high sustained speeds on a Highway/Interstate.Then it can take a little longer to switch off.I have never had a flat battery using one if that's a concern.In Winter/cooler times the Efan is hardly used of course and if it does come on the cold air the fan draws through soon cuts it off.

As my wiring,as per my pages,is tied to the Ignition supply the fan is not left on when you park the bike.Unlike cars there's no real after heat problem with our engines as they are open to the air so cool naturally.I tested all things with my Infra red temp gun and my Cylinders start to cool down from 85 Deg C normally once stopped and everything off.



The apparent simplicity of my system belies the fact that I tried different things over a period of 18 months before publishing some years ago until I was happy that it was simple,cheap and had no problems and nothing would hurt the engines.
 

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Discussion Starter · #12 ·
The reason I was curious was it seems Reg mounted his on the bottom, but what struck me was the huge red X. Made me wonder if there was some serious problems with mounting them on the top. My fan wires are closer to the bottom, but really doesnt make a difference since the cable have to go up anyway to the switch/light and back to the battery area (I think there is an ignition powered line back there, but if not I still want the ground going back there.



Tested the fan and while running it draws about 1.8AMP, but looks like the startup inruch is around 3AMP. Hope that wont cause an issue with the Stator or bike power.
 

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Ahh yes

The red X

I fitted one at the top first and it came on way too early and stayed on

So....

I removed it and put the other at the bottom figuring the coolant

will/should be cooler

this works well but as I said before, seems to be a wee bit on the early side



BTW the thermo switch is on the ground side of the relay

coil and only has to handle about 130mA so i doubt the

contacts will suffer from arcing



Not one to do things by half

I fitted an 'Organically controlled tactile response switch' as well

but it hasnt been needed

As you can see, its rather cunningly disguised as a bit of wire which when shorted

to the bars operates the relay/fan.

Its the finishing touches y'see?

not everybody bothers

 

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AS for running power

My led voltmeter is quite sensitive and will drop an led when the indicators are

on, so will the brake lights and headlights

but the fan has no effect on it at all so I doubt its using much.

It comes on with the right hand amber led on the wubber ducky and this corresponds to

a bit hot

Later, I'll fix it so it comes on with the clear red leds centre/above

 

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Discussion Starter · #16 ·
Well, since being in Canada, I was not able to source and nice blue wire like you have, so had to settle for the poor mans fan switch. Plate all nicely baked in the oven and the wife will never know :) (oh, have to remember to put the cookie pan away and get rid of the wire holder i used). With any luck the thermo units will come in the mail tomorow and I can finish this off (ordered 2 80 and 1 75deg units, think I will use the 75)

Pics kind of crappy as its preet small, but i did get a nice pic of a piece of my hand held scope sitting on my new dremmil drill press lol I love toys



 

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Yeah well, you wouldnt get that blue wire out in the colonies.

They dont sell it to just anyone you know

Special stuff that, very special..




Hand held scope? I'm so frickin jealous

I gave my old one away and wish I'd kept it now

Not handheld or anything fancy mind you, but there have been a few times

I wish I had the use of one.
 

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Discussion Starter · #18 ·
Did the same thing, had a dual trace one and ton of electronic stuff, and when I stopped playing with electronics I got rid of it all (or should I say the wife helped lol). When I decided to make digital guts for my gauges I realized I had to get some new stuff (like a temp controled soldering iron) and saw it at the store ... figured, what the hell lol.

Actually surprised how much electronics parts I still had in multi drawer cabinets I burried, still have lots of stuff as when I bought Parts It was not a few and there, it was hundreds. Since I worked at a place doing eng and did some work from home, when I needed some resistors I used to order boxes of 1000 lol Even have about 100 of the old style processors I used to use 6800 series and the single chip 68705. I would have sude it but my emulation board got chucked
 

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The reason I was curious was it seems Reg mounted his on the bottom, but what struck me was the huge red X. Made me wonder if there was some serious problems with mounting them on the top. My fan wires are closer to the bottom, but really doesnt make a difference since the cable have to go up anyway to the switch/light and back to the battery area (I think there is an ignition powered line back there, but if not I still want the ground going back there.



Tested the fan and while running it draws about 1.8AMP, but looks like the startup inruch is around 3AMP. Hope that wont cause an issue with the Stator or bike power.
I too mounted the temp switch on the bottom, first a 75 then an 80 as the 75 came on too early. My fan draws 4 amps! (Maybe I should get another) Consequently I power it through a solenoid that taps directly from the starter solenoid. I used switched ignition to the solenoid coil and ground the coil with the temp switch. This avoids putting high current loads on the temp switch and the ignition switch. There is also a fuse on the power feed from the starter solenoid. All of that tucks nicely under the seat with only the fan power wire and the solenoid ground wire going to the front of the bike. The fan is grounded to one of the bolts securing the tach adapter/cam support housing.

Route and secure the wiring so you don't get the telltale tick-tick of wires hitting the fan blades---don't ask how I know.
 
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