After sitting in my garage and more thoroughly reading my Rubicon owner's manual, I noticed that Honda recommends running a certain spark plug for temperatures below 41 degrees F (5 degrees C). I'm assuming the heat ranges are different between the plugs that run above 41 degress vs the ones that run below 41 degrees. I did not do this last winter and I had start problems with the Rubicon when it was cold. Is it safe to assume that I'll have a much easier time starting the Rubicon this winter if I put the recommended spark plug in when the weather gets colder than 41 degrees? Has anybody noticed a difference between the 2 plugs?

 

We discussed this in this post: http://forums.atvconnection.co...keyword1=spark%20plug


A hotter plug just has a longer ceramic nose on it, so it disipates heat to the engine block more slowly. This means that the combustion chamber will run hotter. On a cold start, a cold plug is a cold plug, and the length of the ceramic won't make a bit of difference. Might help the combustion chamber get up to temp qicker, but when it is dead cold...it is dead cold no matter what plug!

 

Nice diagram: http://www.ngksparkplugs.com/t..._plugs/p2.asp?mode=nml

 

Are you running a lighter weight oil for winter???

 

reconranger, thanks for the replies.

I run 10W-30 in my Grizzly all the time and I run 10W-40 in the Rubicon. One of the mechanics at the local Honda dealer suggested I always run 10W-40 in the Rubicon because "the transmission requires it". I didn't read anything about this in my manual (but I may have missed it). Is he full of crap?

One other question... On the same Rubicon, my choke **** will not stay fully up when I go to start the machine. It tends to fall right back down and I'm forced to hold it up while it reaches operating temerature. Is the adjustment for it somewhere on the cable or on the carburetor itself?

Thanks again

 

If the choke is like all the other Hondas, just tighten the plastic nut at the bottom of the slider. It will increase the friction and it should stay out when you pull it. Don't forget to push it back in after it warms up!

I did a post a while back, asking who changes oil weight with the seasons. You would be surprised at the number of folks in very cold climates who are running relatively thick summer oils in winter. Run whatever your owner's manual recommends, but I bet it probably is 5W30 for winter (???).

Got to go get some hotter plugs for my Ranchers. We ride them mostly in the mountains in winter.

 

on the rubicon there is a primer on the carb. that is for cold weather starting. remove the plastic on the right side of the bike below the seat. push the primer once or twice. and then start it on choke. should be fine. you dont need a different plug.

 

kgcool, Thanks. I was aware of the primer on the carb. Even when I tried that last year, it was a pain to start. On one of the really cold days, it wouldn't start at all. I wonder if maybe I was experiencing fuel line freezeup of some sort. Regardless, when the weather gets below freezing, it's not the easiest thing to start. I hate to say it but an old Polaris 425 Magnum I used to have started much easier in cold weather when compared to the Rubicon.

 

After a couple of winters fighting the hard starting COLD rubicon. I now go into my garage turn key on and just do something else for a minute or two. Let the bowl heater do its thing. It does help

 

how cold does it get where you live?