I haven't done much to my bike yet (Black Spring, Holeshot ATR's) but I have ordered the DG snorkel, Twin Air Filter, and Uni vents. My question is when I did a plug check (only after idle) the plugs were pretty black(only 600miles on it). I realize then that I am running rich which makes sense as that is intended from the factory. I am at 1000ft and plan on installing the snorkel and air filter. Can anyone give me any idea how much those mods alone or with the Nyroc muffler mod leans it out? The answer is probably to install and run some checks but just looking for anyone experience to guide me.

The only problems I have is idling and starting. Starts hard when cold but I now try to give it 1/8 throttle and it helps a little.

Any thoughts would be great!

 

With just the twin air and snorkel you might be ok with the stock jetting. The 650 seems to be jetted rich (mine was) and after opening up the air intake with the same mods my jetting was fine. If you add the nyroc exhaust mod you probably will have to rejet to a richer setting. Keep an eye on your spark plug of course as you already have been doing. Your altitude has been weel documented at nyrocs website for jetting and mod instructions.

Good luck Bob

 

most 650's actually come very lean from the factory, which is why most of us have had to turn out(richer) our screws to 2.5 - 3 turns to make starting a breeze, and minimize any coughing or sputtering when cold. So far, down to 38F or so, my prairie starts cold/choked almost instantly every time. Very very minimal turning over.

Testing plugs with 600 miles on them and after idle is no way to make any determination of your engine's running condition. I'd have someone who knows engines inspect your tuning. If you were rich, likely your bike would start very easily. I'm not sure how much the 1000feet affects jetting, check around. Check your screws and see where they are, by noting their position, and counting how many turns clockwise till it stops.


Good luck! P.S. You may have fouled a plug, did you check both?

 

Thanks for the input. Lightman, you are right about starting. If I am rich it would start "better". Can't help but notice both plugs being black and my dealer told me the 650's come rich. I haven't checked my valves and it is out of my league at least without the service manual which I have on order now.

I plan to run some plug checks at 1/2 throttle and full throttle this weekend even if I don't get the air filter and snorkel. THanks again for the comments.

 

my dealer told me they come rich from the factory for emissions reasons, and most of the posts on the forums seem to support that notion. good luck.