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Discussion Starter · #1 ·
Well, I took my first LONG ride, a trip from Abilene TX to Denver CO and back.



It was GREAT, and the bike was rock solid, right up until I was coming back, 200 miles from home, and suddenly felt coolant all over my legs. Pulled off and it wasn't long before I had found the problem. Two fan blades had sheared off (funny I never heard anything...) and the radiator is punctured near the bottom.



Ordered a new rad today, as well as an electric fan assembly off a '97 ninja 600.



I'm going to do this project:



http://choppercharles.com/cs/forums/144697/ShowPost.aspx



Can someone help me with the normally-open thermo switch?? Shep's links (found here) are to UK-sites, and besides I think I need the 80 degree one rather than the 75 (all in Celsius), because I like to fill the radiator up to the top.



Thanks in advance! You guys are awesome.
 

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Sorry I can't help you out with your CX, but I am sitting on a Brand New GL500 (Silverwing) Radiator. I'm looking for best 'reasonable' offer. For those that don't know, the GL radiator is different than the CX - where the CX 'top pipe' comes out at an angle from the left side, the GL radiator goes straight back.
 

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Well, I took my first LONG ride, a trip from Abilene TX to Denver CO and back.



It was GREAT, and the bike was rock solid, right up until I was coming back, 200 miles from home, and suddenly felt coolant all over my legs. Pulled off and it wasn't long before I had found the problem. Two fan blades had sheared off (funny I never heard anything...) and the radiator is punctured near the bottom.



Ordered a new rad today, as well as an electric fan assembly off a '97 ninja 600.



I'm going to do this project:



http://choppercharles.com/cs/forums/144697/ShowPost.aspx



Can someone help me with the normally-open thermo switch?? Shep's links (found here) are to UK-sites, and besides I think I need the 80 degree one rather than the 75 (all in Celsius), because I like to fill the radiator up to the top.



Thanks in advance! You guys are awesome.




No problem.



http://cgi.ebay.com/NO-Thermostat-T...471?pt=LH_DefaultDomain_0&hash=item3cab5a929f



Buy the 10 and others on here can use them instead of the 75 Deg C ones if they too wish to fill the rads full.They are as,"Cheap-as-chips<

fries>) as we say over here.Usually take less than two weeks to come from those sellers.



I have no problem running my CXs with the coolant level about an inch above the cores but I can understand those who wish to have the Rad full.



You will not regret doing the modification.You are not the first person to have the Rad take out by the Mechanical fan and I suspect there will me more as the bikes get older and the years pass.



PS

If you are fitting the fan behind the Rad make sure it's wired to Suck and not Blow
 

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I'd be down for two of those 80 deg switches. Just let me know if you go for it! I'm looking to do the electric fan mod both of my CX's this winter.
 

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Discussion Starter · #5 ·
Thanks, Shep! I ordered them.



I hope you're right about the mod--right after I ordered the ninja fan I had a moment of doubt, thinking I was getting in over my head and ought to have just gotten another mech fan. We'll see how it goes!



Hopefully the wiring will prove to be within my abilities. It's about all I can do to solder a wire to something. If I get really ambitious, I may also try and wire in a toggle switch so that I can choose to start the fan before the temp reaches 80 C. That way if it's a hot day and I'm sitting in traffic, I can start the fan before it starts to get hot.



Midgtmn, check with me in a couple weeks, and I'll send some switches your way!
 

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How do you run the radiator less than full?



At least, my 82 GL500 has a pressure cap and overflow bottle which is designed to purge the air at the top and keep the system filled to capacity with coolant. You can underfill the radiator but it will soon purge itself of the air through a few heat and cool cycles.



Am I missing something?
 

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How do you run the radiator less than full?



At least, my 82 GL500 has a pressure cap and overflow bottle which is designed to purge the air at the top and keep the system filled to capacity with coolant. You can underfill the radiator but it will soon purge itself of the air through a few heat and cool cycles.



Am I missing something?
uh oh... here we go again!
 

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Discussion Starter · #10 ·
Update 9/27:



Got it all together, and IT WORKS! The suspense was killing me while I sat there with the bike running, waiting for the fan to switch on at 80 C, which it did after about 10 minutes or so.



The fan never did switch off, not even after riding at normal speeds.



I went back and looked at the ebay link



It looks like the "reset temperature" of this switch is 65 C.



This may be so low that once the fan starts up, it will never shut off again as long as the bike is running.



I may just leave it as-is, but thought this might serve as an FYI to others doing this project. Maybe try to find one with a higher reset temperature so the fan can cut off again.



Also, if you plan the placement of the new fan carefully, you won't have to remove the old fan shroud.



Excited to be rolling again!
 

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Mouser, Digi-Key, Arrow etc will also have the switches.



My final design on the variable speed PWM controller should be finalized and tested by late this week or early next. I'm trying to build some extra functionality into it yet keep it as simple as possible.
 

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Discussion Starter · #13 ·
Did you replace the fan guard with anything?



I started to take it off, but realized that I was unscrewing a bolt that went clear into the cylinder head casing. And then I wondered if leaving the guard on would help protect the fan from dirt and grime.



So do you think the switch listed on ebay here may be better as it will reset at a higher temperature?



I've also PM'd Shoreride to see if he can spare me a switch. Until then, at least I'm operational.



Thanks Shep!
 

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Did you replace the fan guard with anything?



I started to take it off, but realized that I was unscrewing a bolt that went clear into the cylinder head casing. And then I wondered if leaving the guard on would help protect the fan from dirt and grime.



So do you think the switch listed on ebay here may be better as it will reset at a higher temperature?



I've also PM'd Shoreride to see if he can spare me a switch. Until then, at least I'm operational.



Thanks Shep!


No I left the guard off.The electric fans themselves are protected so no need for it.If Shoreride doesn't have any I would send you two 75 Deg C N/O ones for $10 inc postage but the daft thing is you can get 10 for less than that from China.If you want to run with a full radiator then use an 80 Deg C N/O switch or wait for Marshall's variable one.Then you can fine tune to your needs




Ride safe in knowledge that even now you cannot ever,"Grenade" the Radiator again
 

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Mouser, Digi-Key, Arrow etc will also have the switches.



My final design on the variable speed PWM controller should be finalized and tested by late this week or early next. I'm trying to build some extra functionality into it yet keep it as simple as possible.


Can't wait to see the design.



I got my zx6 fan hooked up yesterday with the 75deg switch. Seems to be doing quite well at keeping that needle right on the break between the thin/thick lines. Can't say it's ever let the fan shut off though.



I didn't have any thermal epoxy, so I scuffed the surface of the rad and switch, and just soldered the thing on
 

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Can't wait to see the design.



I got my zx6 fan hooked up yesterday with the 75deg switch. Seems to be doing quite well at keeping that needle right on the break between the thin/thick lines. Can't say it's ever let the fan shut off though.



I didn't have any thermal epoxy, so I scuffed the surface of the rad and switch, and just soldered the thing on


If you drop the coolant level to around an inch above the radiator cores it should cut off as per a car normal cooling system.
 

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If you drop the coolant level to around an inch above the radiator cores it should cut off as per a car normal cooling system.


That's where it's at. I also haven't ridden enough yesterday to really see what it's doing
 

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That's where it's at. I also haven't ridden enough yesterday to really see what it's doing


You may find after several heat cycles it will settle down.Remember that checking things whilst static will give false results as there's no real air cooling.A massive amount of air gets shoved past the engine whilst in motion depending on the speed you are doing and of course ambient temperatures also affect things as does coolant mix which should be the stock 50/50.



If ever you do a coolant flush in-bike there will be residual flushing fluid left in the Water jackets if not drained using the 10mm drain bolts.This may weaken the Coolant mix a little so you can raise it to say 55/45 to compensate or just add a half a cup full of pure coolant to the rad.
 

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Yeah, I really have no idea if the fan is on while I'm riding. Only at stops can I hear it...even then it's pretty quiet.



On another note, I think this bike may have had the shattered fan problem before (among other things like being laid down at least once on each side). The inside of my radiator is pretty beat up several areas of completely flattened fins. I may be on the lookout for a better condition radiator this winter.
 

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When I tested my 1st Efan I stuck a 12v LED across the switch and taped it to my bars in the middle so it came on when the fan came on.Some one on the old forum fitted one into his Warning lights area I think.Very snazzy
 
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