my brother has an 05 450 and says that it will not start when cold. warmed up not a problem. any ideas?

 

The only difference between a cold engine and a warm engine is the choke circuit.
That is the first place I would look.
I would also check the valve lash, just because.

 

Cold air is denser than warm air, so the engine gets more oxygen. This upsets the fuel/air mixture (jetting), and makes things a little lean. Plus, Honda jets lean at the factory to meet emissions standards, so cold air can push it over the top.

It has a pumper carb, so push the throtle several times before a cold start and that will inject raw fuel into the carb and prime the system. That and full choke, and mine starts one or two kicks every time......

Also, it helps to run an oil that is thinner in winter. At least a 10W30, and probably a 5W30 in really cold areas. Thick oil will bog the crank when cold, and doesn't get pumping quickly enough to protect the engine. Remember....most engine wear happens at a cold startup, so running an oil that is pumpable is important!

I run Redline MC 10W30 in the R, and Maxima 530MX in my utilities which get ridden in the snow. Both are ester synthetic, and very pumpable in the cold.

 

I use the same cold start up procedure as Recon and it starts first kick every time.

 

hey guys what do you mean a pumper carb?I just posted the same problem,never saw this post.

 

Like a lawn mower where you prime it before you attempt to fire it up. Pump the gas about 4-5 times, leave the throttle closed and then kick it.

 

<div class="FTQUOTE"><begin quote>Originally posted by: woody64

hey guys what do you mean a pumper carb?I just posted the same problem,never saw this post.</end quote></div>

Pumper carb, means it has an accelerator pump. When you stab the throtle it injects raw fuel, to give you a more instant throtle response. If you use this on a cold start, it will prime the carb for you.

On the other hand, on a hot start it works against you. On the 450 never touch the throtle on a hot start! If you inject fuel, it will flood it out and you will be kicking all day to clear it out of the carb.....

 

<div class="FTQUOTE"><begin quote>Originally posted by: woody64

hey guys what do you mean a pumper carb?I just posted the same problem,never saw this post.</end quote></div>


However.....your Rancher does not have a pumper carb. It does however have a carb heater!

 

Thick oil issues.....

http://forums.atvconnection.co...tid/21/threadid/556810