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Thread: My Bike runs HOT. . . Why??? Reply to Thread
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  Topic Review (Newest First)
02-01-2012 11:49 PM
b.miller123 Spal pusher fan: $35
Manual fan switch: $10
Lower thermo switch (SP1 only) $15

If it gets extremely hot where you are:
radiator shrouds: $300 (there is a set for sale here or speedzilla for $250 right now)
front mount radiators $900 (, they always sell out so actually call them if you are serious)

02-01-2012 12:06 AM
jondog9 I've done the switch mod, in all reality, I think it keeps the bike about 5 - 10 degrees cooler on average, unless it's 100 degrees outside. In moderate temps like 70 -80 degrees, my SP1 ran a max of 185-190. Maybe 200 at the red light, but get moving again and it drops back down. Now when it's less than 70 degrees outside, the bike runs around 175 most of the time. Right where the thermostat is just open.
01-31-2012 09:00 PM
Hig Here's more info on the switch mod.
01-31-2012 09:00 PM
Originally Posted by James_03_rc View Post
With out looking at the there anyway to drain the block?? Like pulling the water pump or anything?

You could do that but why? Your lower line is the drain point on the water pump.

Just drain and keep flushing until clear with the distilled water.(Make sure it gets hot enough to open the thermostat!!) Repeat the draining and fill with Engine Ice, or your favorite coolant...
01-31-2012 07:46 PM
gts455 Is it an SP! or an SP2? If its an SP1 you can spend about 15 dollars at autozone and get a direct replacement switch which will turn your fan on sooner at 185 degrees. You just simply replace the screw in switch in the right side rad. Simple mod that will help keep the temps from getting to hot.

Also flush out the system with DISTILLED water. Make sure there is no corrosion or residue build up. MAke sure its topped off after and that is burped properly. Also check your rads themselves. Make sure the fins are good and not all bent blocking airflow.
01-31-2012 07:02 PM
James_03_rc With out looking at the there anyway to drain the block?? Like pulling the water pump or anything?

01-31-2012 10:42 AM
Originally Posted by 1971allchaos View Post
Jondog- I have read most all the info , compiled on this topic.. Here in the eastern mountains, we don't have the temps, ya'll experience.
How much of a difference- removing the one fan, make?
I don't understand your question?
I only removed the fan for cleaning, I re-installed it.
01-31-2012 08:07 AM
1971allchaos Jondog- I have read most all the info , compiled on this topic.. Here in the eastern mountains, we don't have the temps, ya'll experience.
How much of a difference- removing the one fan, make?
01-31-2012 12:40 AM
jondog9 Toooo funny, that's the second time today I was asked that. I'm being lazy - here's a cutnpaste..

Saw your thread about draining the coolant during a search on the board ( ) and had a couple of questions if you don't mind (I have the service manual & read through chapter 6 already):

1 - How many times did you have to drain/refill/flush to get the distilled water in there to drain out looking "clear?"

Or, was it not possible until you removed each radiator and flushed them out?

2 - Was it a pain to "burp" the cooling system of air after refilling with new coolant? One or two attempts or several?

3 - I wasn't clear on this after reading chapter 6, but after burping the air out and letting everything cool off again, do you top off coolant at the radiator itself are you supposed to top off at the recovery tank instead?

Got a couple bottles of Pro Honda HP coolant in the garage, but might wind up splurging for Engine Ice - decisions, decisions...LOL

1. twice, I think I use 4 gallons of disstilled water.
I wanted to remove every bit of water from the system after. You have to remove the rads to do that. So I removed both rads, removed the fan, (SP1 has only 1), and cleared all the hoses too.

2. The burping went exactly as it said in the manual. Not a hassle at all. Start the bike, have the cap off, watch your temp closely as she warms up. Once she hits 174-180 the thermostat should be full open and you'll have full circulation of your coolant. You can see the coolant actually start to flow pretty fast. That's how you know your thermo is open. That's all good. Within a a minute or so, you'll see airbubbles burp up. It's like waiting for popcorn to finish cooking. When there's no more burping, it's done.

3. When the bike is completely cool, the overflow level should right at the mark on the bottle, bike standing up. If it's to full, it'll overflow and drip out the hose. And splash all over. How do I know?

Have a fresh rad cap, or pressure test yours. Take your overflow bottle off and clean it out real good. inspect , clean, all the hose connections. Make sure the smaller hoses flow freely. If you do all that, your flush should go problem free.
Engine Ice. Good luck bro!
01-31-2012 12:30 AM
Dee Money 916
Originally Posted by jondog9 View Post
I've been riding all around lately in this killer weather too. That sounds just a little hot. If your rads are in good shape, hoses all clean and clear, radiator cap check, you should only be running around 180-190 in town, mine cools to 174 on the fwy for now. In summer when it's around 100, when I do ride which isn't a terrible lot, I've seen 224 max, usually aorund 200 - 220. That was average for about 8K miles this year. Engine Ice - Best stuff for the street-only I've tried yet.
I know thats what I think too. . . it hit 218, after riding for about 20 minutes of street traffic, but still. . . to me (especially with how cool the weather has been) 218 is VERY HIGH. . .

Is flushing the radiators a difficult task on the RC? I never really got into physically doing my own repairs on the RC's. . . I have on other bikes, but not the RC (w/ the two radiators) I would like to slap some engine ice in there this weekend, but kinda of reluctant bcuz I dont want to mess shyt up, LOL!!!!
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