Silicon Hose Temp Change

Greetings:

I’m curious if anyone who has changed to silicon hoses have noticed a big drop in temps?

I changed to AS3 hoses; added a new OEM thermostat and rebuilt water pump. Now on a 75 degree day, I’m hard pressed to get above 150 degrees cruising down the road. On a 60 degree day it can run at 120. Before the updates, I ran around 172-179.

Scares me a bit on cooler days though I’m told by my tech that it’s fine. I’m also told that race bikes use silicon hoses because they allow the motor to run cooler.

Not sure what to believe. One thing for sure, the bike takes a bit to warm up now. And I’m getting it up to 150 before I ride.

At a stoplight it pops right back to 200 plus.

Gary

 

Sounds like your thermostat is not regulating at all! Possibly jammed open. Did you do the work yourself? Almost seems like the thermostat is missing.

Slow warm up, very low riding temps are indications of an open t/stat.
Running continuously at low temps is not good for both oil and engine = Higher friction, water not being evaporated off, friction modifiers not at good operating temps etc.

Surprised your "tech" suggests it's fine to run a very cool engine, it most definitely isn't.

 

I doubt the choice of hoses will run cooler....... agree with Grum, thermostat isn't working properly.

 

I guess I should have pointed out that this is the second thermostat I've installed. Both OEM. And both doing the same thing, Seems funny that I would have two new Honda thermostats that are not working properly.

I do agree that low temps do not seem right. I guess I have two choices, ride when its warm out only or start throwing more money at the issue.

Time to talk to a different tech.

 

I doubt that it would affect your operating temps, but anything is possible. I can tell you one thing though, you will smell antifreeze/silicon wafting from the bike. If they were chinesium knock offs I would be concerned but all mine are real deal Samcos. Thats my two cents, btw - I have them on all my bikes which number three. Peace

 

I replaced the original 1999 hoses with AS3's on Monday. I haven't noticed the temperature running cooler due to the silicon hoses.

 

I think you might need to do some checks on the ECT Sensor. It may be sending you incorrect temp info. Or it may be a high resistance connection up at the instrument panel, or poor connection at the ECT. Needs checking.
Is your bike a 5th gen and do you have the Service Manual?

 

Race teams use silicone hoses because they do better in extreme temperature environments and are typically stronger when it comes to burst pressures. They don't have any real effect on the engine running cooler, except for the fact they tend to keep the coolant inside the hose in extreme situations.

 

That temperature behaviour is specific to the thermostat being held open and nothing to do with the hoses. Are you sure it has been oriented as per the service manual?

 

I was the opposite. AS3 hoses + thermostat and went from barely cracking 160F on the highway after 20 minutes, to 170F within 3-5 minutes. And yes, your mechanic is just wrong... 120F is way too cold.

You can verify if the thermostat is the issue or not (at least on 5th gens) if the LH radiator slowly warms up with the bike. I've noticed that after the thermostat swap, the LH rad stays fully cold until the thermostat opens, then it gets hot really quickly

 

Yes, 5th Gen. I’ll look into the ECT sensor.

I have the Honda manual and a Honda tech did the work. I have to assume he did the install correctly. He’s been around a long while and I do trust him. I also smell coolant now. No drips though.

Spoke with my motorcycle race shop today. They’ve done a lot of work to the bike as well. They didn’t seem too concerned either since the bike warms right up when not going down the road. In any event, I’m not worried about 150 degrees. I’m worried about the temp when it’s 60 degrees outside. If it’s runs at 120 when it’s 60 outside I won’t ride it.

 

I'll check this out next. Thanks