I took mine off, and it has become a vent fan for my slider making area. :)
But, I don't think it will last long as it's not meant for continous use. Which got me to thinking about this question.
If you HAVE taken yours off, please see my classified ad.
The gravel in the carosel at RA took care of that!
Dawn :D
I'm a "did, put back on".
I just couldn't justify the loss of 1/2 a pound or whatever over the fact that I was hitting 240* after each sprint. :o
Didn't take long to learn that lesson.
Now she stays nice and cool, never gets over 215. :)
Wow! That's hot!
After a sprint on teh SV in 90 degree weather, it didnt get above 210.
I took mine off. After gutting my thermo the highest engine temp I saw at Daytona was 175 and that was with a strip of duct tape over the center of the radiator!!
So, removing the restriction from the thermostat DID help?
There was a discussion about it recently on teh SV board, and one thought was that removing the guts would cause the water to flow faster, and not give it enough time to dissipate heat in the rad.
What's a rad fan? ;)
Buells don't need no steeenking rad fans...
QuoteSo, removing the restriction from the thermostat DID help?
There was a discussion about it recently on teh SV board, and one thought was that removing the guts would cause the water to flow faster, and not give it enough time to dissipate heat in the rad.
I'd say so. I had my engine built by New England Performance and Pat Doyle who runs the shop says its a standard practice for him.
My engine is bored +3mm over and even with a 7* ignition advance it never gets close to overheating. Daytona was the first time that I actually took the duct tape off the radiator (cuz I was paranoid and didn't have any Water Wetter in the system).
Originally, when it was running so cool (normally 140*) we though it was just running super rich but i've had it custom dyno tuned and its F/I curve is dead smack on.
PJ, don't XBs have a fan for the rear cylinder, though? :D
What may work for one engine may not work for another. I don't know if an inline 4 would create more or less heat than a twin. The difference in size between the combustion chambers may be a difference in the heat generated, and the cooling passages in the engine are another factor.
I would caution against removing or boring out a thermostat unless you know it has been used on your application with success.
Dawn :)
QuoteWhat's a rad fan? ;)
Buells don't need no steeenking rad fans...
Yea... what Paul said! ;D Yes the XB's do have a cooling fan. No radiator tho. Just used for cool down if I am not mistaken.
QuotePJ, don't XBs have a fan for the rear cylinder, though? :D
True, they do. Helps keep the rear cylinder running the same temp as the front in slower traffic conditions. Since we don't see too much stop and go traffic at the track, I removed it...
Dawn, you are on the right track. A 4-cylinder will have more combustion chamber surface area and will produce more friction heat than a twin of equivalent displacement. Just look at the radiators of a twin and a 4-cyl sitting next to each other, the twin's will be smaller.
As far as thermostat/no thermostat, there will be an optimal coolant flow rate, and it will be different for every engine, radiator size, radiator construction, etc. If you wanted to put a 2 temp gauges on the bike, one at the inlet and one at the outlet of the radiator, you could run experiments with different size orifices replacing the thermostat and determine the optimal case. As an example, I have the factory race prep manual for my '64 Triumph TR-4 (the four wheeled kind) and it says to replace the thermostat with a restrictor plate and gives the proper orifice dimension. That car also uses a special thermostat stock that is more restrictive that a standard thermostat. A standard one will fit in the housing, but the car will run hotter than with the more restrictive special (read: expensive) thermostat.
-z.
(for the record my R6 has a thermostat and fan, my wife's MZ has a thermostat and no fans, and her TZ250 obviously has neither)
My fan wasn't all that rad. Rather heavy. But you can't have it. It's a spare for my streetbike (MZ Replica). That bike's got a lot of spares now. ::)
If a thermostat fails in the closed position, you may smoke an engine.
For our racing applications, you don't need a thermostat. Tape will be great if you need more heat in the engine...tape.
I don't have my fan on. Usually, you've moving faster than the fan goes, so it doesn't have much use.
But, like Greg said, it can be used to cool down the coolant in the radiator after stopping.