# Using a fluid trainer outside in winter



## love4himies (Jun 12, 2012)

I live in Canada and would like to use a fluid bike trainer outside in my screened in porch during the winter (too hot in the basement as that is where the wood stove is). I hate being too hot when I work out so I thought it would be great to use the trainer outside. Plus, I have beautiful scenery to look at including wildlife.

Does anybody know if you can use a trainer outside in freezing temperatures or will the fluid freeze and ruin the trainer?


----------



## looigi (Nov 24, 2010)

Should check with the manufacturer, but in my experience, the fluid is an oil which won't freeze but will become significantly more viscous at low temps. Also, the cold tire will have less traction on the roller. Together, those factors could lead to problems depending on how cold it is.


----------



## Peter P. (Dec 30, 2006)

Assuming the manufacturer didn't go "cheap" on the fluid, it will not expand as it heats up from use, thus maintaining a constant viscosity regardless of temperature. Most fluids, such as water, expand as they heat up.

Your fluid will not freeze. In fact, riding the trainer will cause the fluid to heat up regardless of whether it expands or not. The heating from your riding the trainer will keep the fluid, and the resistance unit, nice and warm. If you place your hand on the resistance unit after a trainer session you'll see what I mean. Some manufacturers even warn the user to not touch the unit after a session because it may be hot.


----------



## love4himies (Jun 12, 2012)

Thanks guys. When I mentioned what I wanted to do to the LBS, they didn't seem to have any concerns, but they may have thought I was nuts.


----------



## looigi (Nov 24, 2010)

Peter P. said:


> Assuming the manufacturer didn't go "cheap" on the fluid, it will not expand as it heats up from use, thus maintaining a constant viscosity regardless of temperature. Most fluids, such as water, expand as they heat up...


??? Note oil viscosity vs temp graphs . None are horizontal lines.

https://www.google.com/search?q=oil...oCYDg&ved=0CEQQsAQ&biw=1530&bih=1017#imgdii=_


----------



## den bakker (Nov 13, 2004)

if you're worried about it just take the trainer outside when you need it. the resistance should keep it warm. or you need to pedal harder


----------



## love4himies (Jun 12, 2012)

den bakker said:


> if you're worried about it just take the trainer outside when you need it. the resistance should keep it warm. or you need to pedal harder


I would have preferred not to have do that, but if I can't get confirmation that it won't hurt the trainer, I will.


----------



## nOOky (Mar 20, 2009)

HTFU

I've used my trainer outside below freezing before, you probably won't wreck anything if you do, but I would also recommend taking it back inside when you're done.


----------



## den bakker (Nov 13, 2004)

love4himies said:


> I would have preferred not to have do that, but if I can't get confirmation that it won't hurt the trainer, I will.


now what I would not recommend it to use aluminium rollers if there's snow on the tyres.


----------



## tlg (May 11, 2011)

den bakker said:


> now what I would not recommend it to use aluminium rollers if there's snow on the tyres.


Does that mean you can't use an aluminum bike or aluminum wheels if there's snow on the ground?


----------



## den bakker (Nov 13, 2004)

tlg said:


> Does that mean you can't use an aluminum bike or aluminum wheels if there's snow on the ground?


how much friction do you think there was between the tyre and the roller?


----------



## tlg (May 11, 2011)

den bakker said:


> how much friction do you think there was between the tyre and the roller?


Ahhh gotcha. Rollers. I thought you were talking about the spindle on trainers.


----------



## jspharmd (May 24, 2006)

My thought wasn't what would happen to the trainer (although, I would probably take it inside between rides), but I was wondering what you would wear when doing this ride. Without much wind, it would be interesting to see what keeps you comfortable without too much sweating.


----------



## Peter P. (Dec 30, 2006)

looigi said:


> ??? Note oil viscosity vs temp graphs . None are horizontal lines.
> 
> https://www.google.com/search?q=oil...oCYDg&ved=0CEQQsAQ&biw=1530&bih=1017#imgdii=_


Those temperature graphs are for engine oil. That's not what's used in a fluid trainer. Also, engine oil's main function is lubrication while under severe heat, which is not the operating environment of a fluid trainer where the fluid's purpose is to provide resistance, not lubrication. I believe Kurt Kinetic uses a silicone liquid, for example. The Kurt Kinetic fluid trainer is rated to be useable in temps from -50 to +130 degrees F.


----------



## Kerry Irons (Feb 25, 2002)

Peter P. said:


> Assuming the manufacturer didn't go "cheap" on the fluid, it will not expand as it heats up from use, thus maintaining a constant viscosity regardless of temperature. Most fluids, such as water, expand as they heat up.


So is it your contention that the reason a fluid would become less viscous with increasing temperature is because it becomes less dense? If so I suggest you take a course in physical chemistry, materials, fluid mechanics or polymers where you will learn that your contention is incorrect.


----------



## Alaska Mike (Sep 28, 2008)

Another option is to get a LeMond. The fan would be less influenced by the temperatures outside.


----------



## looigi (Nov 24, 2010)

From Saris on their fluid trainers: "No we would not recommend this (store or operate at or below 32F). It’s not so much the issue with the fluid, but rather the seals that keep the fluid from leaking. If these expand and contract too much they can crack and cause leakage. I would recommend keeping it inside during the winter months."

Of course Kurt fluid trainers don't have spindle seals as coupling to fluid unit is magnetic rather than direct.


----------



## love4himies (Jun 12, 2012)

nOOky said:


> HTFU
> 
> I've used my trainer outside below freezing before, you probably won't wreck anything if you do, but I would also recommend taking it back inside when you're done.


Now that looks better than being on a trainer! However, I don't know of any paths that I can bike on in the winter. We have a 40km MUT that runs parallel to the highway I live on, but residents pile the snow from their driveways on it, so it's not walkable or rideable.


----------



## love4himies (Jun 12, 2012)

Alaska Mike said:


> Another option is to get a LeMond. The fan would be less influenced by the temperatures outside.


Unfortunately, those are about double my budget.


----------



## mikerp (Jul 24, 2011)

You might want to watch Chainlove for trainers, they have been moving some at good discounts (KK as well).


----------



## vetboy (Oct 11, 2005)

Peter P. said:


> Assuming the manufacturer didn't go "cheap" on the fluid, it will not expand as it heats up from use, thus maintaining a constant viscosity regardless of temperature. Most fluids, such as water, expand as they heat up.
> 
> Your fluid will not freeze. In fact, riding the trainer will cause the fluid to heat up regardless of whether it expands or not. The heating from your riding the trainer will keep the fluid, and the resistance unit, nice and warm. If you place your hand on the resistance unit after a trainer session you'll see what I mean. Some manufacturers even warn the user to not touch the unit after a session because it may be hot.


So how come my Kurt Kinetic gets easier after a few minutes of warm-up?


----------



## Peter P. (Dec 30, 2006)

Kerry Irons said:


> So is it your contention that the reason a fluid would become less viscous with increasing temperature is because it becomes less dense? If so I suggest you take a course in physical chemistry, materials, fluid mechanics or polymers where you will learn that your contention is incorrect.


What I'm saying is the silicone fluid is supposedly thermally stable in the application of a fluid trainer and the heat ranges it would see-it's rate of expansion my be zero or negligible. Outside of that range, things could change.


----------



## Peter P. (Dec 30, 2006)

vetboy said:


> So how come my Kurt Kinetic gets easier after a few minutes of warm-up?


I could only guess-perhaps the fluid quickly rises to a temperature range where it's rate of expansion is zero or stabilizes and Kurt designed the trainer so the all that matters is the stability of the trainer's resistance after heating up to a specific range.

Or it could be YOU that are warming up and becoming more efficient.

I own a Kurt Kinetic Road Machine and I haven't noticed the trainer being easier to pedal after a period of time.


----------



## vetboy (Oct 11, 2005)

Peter P. said:


> I could only guess-perhaps the fluid quickly rises to a temperature range where it's rate of expansion is zero or stabilizes and Kurt designed the trainer so the all that matters is the stability of the trainer's resistance after heating up to a specific range.
> 
> Or it could be YOU that are warming up and becoming more efficient.
> 
> I own a Kurt Kinetic Road Machine and I haven't noticed the trainer being easier to pedal after a period of time.


Nope. My power meter vs the speed on the trainer says that it gets easier as the kk heats up.


----------



## Kerry Irons (Feb 25, 2002)

Peter P. said:


> What I'm saying is the silicone fluid is supposedly thermally stable in the application of a fluid trainer and the heat ranges it would see-it's rate of expansion my be zero or negligible. Outside of that range, things could change.


Yes, silicones are thermally stable, but that does not reference their viscosity vs. temperature relationship but rather their resistance to chemical degradation due to temperature. Rate of thermal expansion and viscosity changes with temperature are NOT the same thing. The reason silicone fluid viscosity is less temperature dependent is a molecular entanglement issue. The coefficient of thermal expansion of silicone fluids is essentially the same as petroleum based oils.


----------



## MR_GRUMPY (Aug 21, 2002)

I use a trainer in an unheated garage, all winter. After 5 minutes I'm down to bibs and a T-shirt. I use towels to protect my headset and front brake. I usually have to clean up the floor afterwords.

I ain't kilt my trainer yet.
.
.


----------



## love4himies (Jun 12, 2012)

MR_GRUMPY said:


> I use a trainer in an unheated garage, all winter. After 5 minutes I'm down to bibs and a T-shirt. I use towels to protect my headset and front brake. I usually have to clean up the floor afterwords.
> 
> I ain't kilt my trainer yet.
> .
> .


How cold does it get where you live? Putting it in the garage was my other option, but the scenery isn't as nice as my back porch.


----------



## MR_GRUMPY (Aug 21, 2002)

When it gets below 20, we usually fire up a propane heater until it gets to be 40 in the garage.
.


----------



## love4himies (Jun 12, 2012)

Santa brought me a Elite Mag trainer. The owner of my LBS uses a mag outside and has not had a problem with it and didn't recommend a fluid one. So now I've got my bike all set up on it and just have to wait for the ice from the ice storm to melt on the deck and I'll be checking it out. 

Edit: exchanged the mag for the fluid. Didn't like the shifter on the mag, it just pi$$ed me off.


----------



## simonaway427 (Jul 12, 2010)

My KK trainer loses resistance as it heats ups....I need to increase speed/cadence to maintain the same power - even during 4 minute intervals.

Trainer Profile | TrainerRoad - Vandever - 4 x 4mins | Times and Records | Strava


----------



## MarshallH1987 (Jun 17, 2009)

I might not leave the trainer outside all night, but there are no issues when using them outside. When driving to early spring races we'd sometimes strap trainers to the roof and drive through freezing temperatures and never had any issues.


----------



## .je (Aug 25, 2012)

Hey old topic, new question! I have had an Ascent fluid trainer for several years and it has worked well. This past winter I moved the trainer to my garage which can be cold, well below freezing. 

In cold weather, not indoor room temperature, the trainer makes a loud clicking noise that is louder when more pressure is applied to the tire. I does not change with a different tire. It sounds like bearings. I'm hesitant to use the trainer since it sounds like it's in bad shape.

So Nashbar got back to me, told me the trainer wasnt designed to be used in cold temperatures. It should have a temp range in the instructions, but i guess it just doesn't. Strange based on any experience I've had with bearings or assembled stuff. Well, now we know.


----------

