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Samco Thermostat bypass kit?

17K views 71 replies 24 participants last post by  ramocs 
#1 ·
Hey guys I just wanted to try and gain a little knowledge on this kit and see if anybody has done this yet. I recently came across the bypass kit from Samco for the 15+ R1 and I'm pretty interested because well let's face it these bikes run HOT. So I took a look at the pictures that are available and it seems like it allows a small amount of coolant into the radiator before reaching the thermostat so it should run cooler but the thermostat is still there and still working. I was just hoping to get a little more insight on this kit and if anybody could shed a little light on this subject that would be great

2015 2016 Yamaha R1 R1M Samco Thermostat Bypass KIT NEW Race KIT Drops Temps | eBay

^ Here's the link to the part so you guys can take a look



^ And the pictures available for the parts


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#6 · (Edited)
A few race bikes we removed the thermostats; not a good idea for a street bike unless you want to carry around a roll of duct tape to section off parts of the rad to moderate coolant temps. Especially in the rain since the rain water will drop the coolant temps drastically to the point it could damage the motor.

I'd like to get rid of the whole thermo plastic housing and replace it with an aluminum unit along with crappy oil lines.
 
#8 ·
‎That looks more like a full bypass for racebikes. Lowering the fan Temps in the flash should take care of it I set mine to 205 and it shuts off at 195 I've never seen it above 208 since. Graves also makes a higher pressure radiator cap supposed to help and if you can find a lower temp thermostat that would be the way to go.
 
#16 · (Edited)
:secret.....without a flash, the fans come on at 225F.....so that is where it will sit.....flash it and have the fans come on at 205....problem solved.....

P.S. a thermostat keeps the flow through the engine/radiator at the correct rate so the water can do it's job absorbing and dumping heat. If it moves to fast it doesn't have the tune to transfer to heat. Removing it typically causes more issues than it solves.... also these bikes have like 180f thermostats, so it is well open before the point that the op is worried about it.
 
#19 ·
Then they must have updated the OEM ECU, because though 2014 it was 225.....
 
#22 ·
The other thing that can cause higher than normal temps is a tune that is off in the cruising region.....
 
#23 ·
I can see that but my ECU hasn't been flashed or anything, just running a PCV. I hope thats not screwing with it lol. Oh well. I'll just have to live with it for now. I mean it's not like the bike is getting damaged or overheating I just don't like that it tends to get as hot as it does. Engine ice and lowering the fan temps will be coming along in the near future haha [emoji1360].


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#24 ·
If the tune in the PCV is off then it could cause higher than normal temps.....flashed or not
 
#31 · (Edited)
I was curious, so I called EDR for myself.
I asked if they road tested this kit. EDR said yes.

The average engine temps they had in their warmest months was in the 185℉ range.

I explained I also ride in the colder months and its about 43℉ or so in the early morinings. EDR said they also rode the bike in similar conditions. The engine temps avg about 135-140℉ with the thermostat elim kit.

EDR stated they have not had any issues thus far since starting to sell the kit. Just food for thought n more discussion to agree/disagree.

I did not get into specifics if it was stop n go or highway riding....I forgot to clarify. Sorry

These new gen crossplanes run hot in general yes?
 
#34 · (Edited)
With the thermostat being fully open when the bike is hot I don't see how a bypass kit would let the engine run that much cooler. Notice the operative word in EDR's response........... "average temps of 185". A stock bike probably averages 185 as well.

Where you can get into trouble is riding in a rain storm where the thermostat keeps the engine within the correct operating temperature range. I would use this kit for a race bike; for tge street there is very little to gain.
 
#44 ·
With the thermostat being fully open when the bike is hot I don't see how a bypass kit would let the engine run that much cooler.
A thermostat is valve in a casing. The casing creates a bottle neck, limiting flow. The valve is also not a full flow through and blocks a lot of the opening. This limits flow as well and changes the way the coolant flows inside the coolant lines/jacket.

I would say that with a thermostat fully open, the coolant line is about 40% blocked.
 
#35 ·
:iamwithst an engine that is too cold is not efficient either.....
 
#43 ·
2muchblue is spot on. I run engine ice with a flash&pcv and stock rad cap. Fans are set to 195-205. I rarely see 215*F even on 95+*F in traffic. At the track I only see 185*F when I'm strechin gears. If i short shift I'm 170-180*F on a 80*F day. I would not pull out thermostat unless it was a track only ride. On a cold day ( 40*F) It's hard to keep temps around the 165*F mark(that's my happy place). Just my 2 cents.
 
#50 ·
The purpose of the thermostat is to keep water in the radiator longer, for the fans and wind to cool it. It's made to slow the flow of the system, that's the point.

There are advantages of running an open system, and a system with a thermostat. I've ran open systems on my old R1, but that bike was only raced. If you are experiencing any overheating with a street bike, another option would be larger radiator with a thermostat. I've also seen radiators modified to have double pass sections, so the coolant goes back through the radiator for a second pass.
 
#62 ·
I just scanned the other posts after this and I don't think anybody clarified why we're running a 2 bar cap. The bike comes stock with a 1 bar radiator cap. 1 bar = 14.7 PSI. 2 bar = 29.4 PSI. IN THEORY raising the pressure within the cooling system it will raise the boiling point temperature.


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#53 · (Edited)
I probably should narrow it down to thermostats ... I had no idea that it was there to slow down coolant flow in the radiator to make it more efficient.

All that a high pressure cap will do is increase the boiling point. Maybe fit one if you're running straight water to increase the boiling point, but it won't cool the engine any better.
 
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