Jetting at sea level

Discussion in '610/630' started by flynn_, Aug 23, 2016.

  1. flynn_ Husqvarna
    C Class

    Husqvarna Motorcycle:
    610sm
    Hello guys, I live on the coast so at sea level. As a result, my jetting settings can probably go a fair bit richer than standard.

    I have already adjusted the needle clip by one position richer and now it feels stronger up to 3/4 throttle but then at full throttle it feel flat, presumably because the main jet is now the bottleneck.

    It is currently a 185, I was thinking I could go to a 195 and even if it is a bit rich for the moment I will be straight throughing the exhaust pipes soon.
  2. Flynn Husqvarna
    A Class

    Location:
    England
    Husqvarna Motorcycle:
    none
    Also the lever from the accelerator pump came out of the top hat on the carb so I had to remove it. Now when I open the throttle suddenly (as you would to do a wheelie) there is a delayed response. Can this be compensated for with jetting or do I have to order a new top hat (expensive)?
  3. Flynn Husqvarna
    A Class

    Location:
    England
    Husqvarna Motorcycle:
    none
    Well I have increased the needle jet one jet richer and it pulls harder up to 3/4 throttle but on open throttle it feels flat afterwards so I figure I could increase the main jet size. Current is a 185, do you think I could go to a 195? Or should I just go to 190?
  4. DGA Husqvarna
    AA Class

    Husqvarna Motorcycle:
    2007 SM610
    Other Motorcycles:
    2015 Tuono, 2003 Gas Gas 450 SM
    I had my '07 610 dynoed and the guy (very sharp and reputable bike tuner) said that I should go to a 195 from a 175 that was in there. I'm at about 500' of elevation. Mine has a Leo Vince pipe so it certainly flows better. I also upped my pilot to a 45, my fuel needle is at two turns out, and I've wired my accelerator pump and timed it perfectly as well. Everything else on the carb is stock.

    That being said I could not tell you if it's running better or not. I had it dynoed with the 195 main and now I have a carb problem that I need to solve as I'm running leaner on the main jet after going from a 175 to a 195. Other parts of the power curve look great, except when on the main. Could be a badly machined jet and I'll try another 195 and open up the carb to see if anything else is amiss.
  5. Flynn Husqvarna
    A Class

    Location:
    England
    Husqvarna Motorcycle:
    none
    Just out of interest what did it make on the dyno? I am going to get my 2001 dyno'ed and will post the results up here for anyone interested.

    I have changed the needle position back to 2nd from bottom for the purposes of the dyno.
  6. DGA Husqvarna
    AA Class

    Husqvarna Motorcycle:
    2007 SM610
    Other Motorcycles:
    2015 Tuono, 2003 Gas Gas 450 SM
    I really don't remember, but was told that I'm leaving about 5+ hp on the table due to how lean it is based on what the tuner has seen from other 610's on that dyno. I have the graph at home. If I can remember I'll post it tonight.