Cold crank

[bryanchurch06]

Cranking bike 1st time in a month, kept battery charger on them and they both cranked right up. Bad case of PMS parked motorcycle syndrome, going to idle them for 15 to 20 minutes.

 

[m in sc]

put sidestand up and also run thru gears.

 

[bryanchurch06]

put sidestand up and also run thru gears.

Thanks i will, didn't think of that

 

[jimzpsd]

If your going to run them for 10-15 minutes, keep in mind its air cooled...have a strong fan blowing on the engine fins to dissipate the heat and avoid "hot spots". Your better off letting it sleep, also you will make condensation in the exhaust, unless it gets to operating temps. Leave it rest, all the new motorcycles are sleeping at the dealerships as well.

 

[bryanchurch06]

If your going to run them for 10-15 minutes, keep in mind its air cooled...have a strong fan blowing on the engine fins to dissipate the heat and avoid "hot spots". Your better off letting it sleep, also you will make condensation in the exhaust, unless it gets to operating temps. Leave it rest, all the new motorcycles are sleeping at the dealerships as well.

I think it was 28dg outside at the time and windy. So I didn't use a fan. Definitely would in warmer weather.

 

[Cpd419]

Anything I start in the winter runs to full temp.

 

[jimzpsd]

Subzero weather is cold too, but you need a fan to dissipate the heat, radiating off the cooling fins does nothing by itself, it needs to be extracted or drawn from the fins. Hot or cold ambient temps mean nothing to an air cooled engine, its the breeze that draws the heat away.

 

[m in sc]

i disagree, and heres why. the point is to get the oil up to temp and burn off any condensation. 10 mins with no fan is just fine, even on hot days. I mean, think about these bike sidling in traffic on a hot day? theres no damage. when you get into any time over 10-15 mins, then it can become an issue. heat will absolutely dissipate on an air-cooled motor w no breeze to an extent for a while before airflow is needed. 9 of my current bikes are air-cooled, they can do a 10-15 minute warmup just fine w no fan. If you keep the oil too cold it will actually promote wear.

 

[jimzpsd]

Not saying it will kill your motor, but it will also not be good for it. Bikes that sit in traffic and get hot eventually begin to move forward and this is the moment of heat extraction vs an engine running motionless and then shut off, hot spots will remain longer and will not be drawn to the "thinner" portion of the heat fins. Many people will run their engines this way because they don't understand the theory of air cooling vs convection. Imagine an engine with an external oil cooler...it too will need air movement through its fins to dissipate the heat efficiently, no air no heat loss, making the cooler useless. People can do as they wish, I was just giving a tip of advice because some folks will run the engine too long without the air supply.

 

[ShieldArc]

Just think about all those cast iron steam radiators in houses.

 

[jimzpsd]

Just think about all those cast iron steam radiators in houses.

Simple, no internal moving parts and is intentionally designed to radiate heat.

 

[m in sc]

heat is heat. heat will radiate thru the fins, and the air coming in will cool it as will the fuel. If it was that necessary, honda would have fit fans from the factory. On vespas, lambrettas, they have crank driven fans due to being in an enclosed housing, and the engine bay will not dissipate heat as well at idle. The surface area of the cyl vs the heat produced on a grom, trail, cub, ct90, etc motor is plenty to keep it cool. Even some aircooled VW motors will use an oil thermostat to keep the oil from circulating thru the cooler until it gets up to temp to combat the over cooling effect the fan has on the motor. Oil, fuel and intake air are all internal cooling factors that seem to be getting overlooked here as well. the oil will keep it Temperate in the crankcases and the head and cyl, more than one might think. walkaround an air-cooled motor with a thermal gun after 10-15 mins of running w no external (fan) airflow, and tell me where its in the 'bad for the motor' range. Elsewhere in this forum i listed videos of me running all my bikes to do exactly what was stated by the OP, these are OLD bikes, some with cast iron cylinders, the all ran for 10-15 minutes with no fan on them. zero issues. put a fan on it after 10-15 mins, prior to that engine being up to temp, and you are keeping the oil too cool and that's more damaging in the long run. sorry, just the truth. also why muti viscosity oils exist . its not for the hotter temps, its for cold startup. hence, 10,5,0 weights on the 1st part of the designation. I mean, do whatever you wish, but the reality is, 10-15 minutes isn't going to do any harm to any aircooled motor being run in open air in pretty much any ambient temperature a human can endure.

 

[dmonkey]

You can literally rotisserie a chicken with a stationary CT125 without it overheating.

 

[TrailBoss]

You can literally rotisserie a chicken with a stationary CT125 without it overheating.

Just when you thought you'd seen it all...

 

[jimzpsd]

LOL, I can truly say "I heard about this on the internet"