N1k Posted March 31, 2010 I recently purchased a 2007 drz400sm and I love it! The previous owner installed a yoshimura rs2 full system..and did nothing else to the bike. After getting a full service done at Suzuki, the mechanic told me that it needed to be re-jetted. I was planning on gathering all the parts/information myself and getting the guys at Suzuki to install them. After having a look at the yoshi site, I found some jetting reccomendations that said I should install: mikuni main jet #145 and mikuni pilot jet #25. Also that I should enlarge the air box opening to 3.625" x 4.5". Is this all the information I need?.. Thanks Share this post Link to post Share on other sites
Wayward Son Posted March 31, 2010 has the air box been modded? Share this post Link to post Share on other sites
N1k Posted March 31, 2010 I haven't checked yet..I'll go have a look now Share this post Link to post Share on other sites
Johnson79 Posted March 31, 2010 get the jet kit and do some reseach on here and you'll be able to gather more than enough information to do it yourself instead of paying a mechanic. Also ignore what yoshi says and cut a hole in the air box only 3x3 along with correct jetting specs Share this post Link to post Share on other sites
N1k Posted March 31, 2010 Nope..the air box hasn't been touched which jet kit? And what is meant by correct jetting specs? Thanks for your help Share this post Link to post Share on other sites
npm My Rides (2) Posted March 31, 2010 Nope..the air box hasn't been touched which jet kit? And what is meant by correct jetting specs? Thanks for your help The James Dean kit is the most complete. Share this post Link to post Share on other sites
707drz Posted March 31, 2010 Obviously you'd get the most out of the exhaust if you jetted and cut the air box but....I'm assuming the if all they did was install the pipe your bike will be fine. if they cut the air box and didn't re jet then you'd have a poorer running engine. Share this post Link to post Share on other sites
N1k Posted April 1, 2010 Does the James dean jetting kit come with everything I will need to re jet? (parts & instructions) Should I cut the air box?..if I do, will there be jetting instructions to suit a modified air box & my yoshi rs2? Share this post Link to post Share on other sites
pi3832 Posted April 1, 2010 Does the James dean jetting kit come with everything I will need to re jet? (parts & instructions) Should I cut the air box?..if I do, will there be jetting instructions to suit a modified air box & my yoshi rs2? The JD kit has everything (including replacement screws for the float bowl, because the stock ones are utter crap), it requires the 3x3 mod (cutting your airbox), and the JD directions cover an after-market full exhaust. IIRC, for an aftermarket full exhaust you just go up to the next larger main. Share this post Link to post Share on other sites
N1k Posted April 2, 2010 Would you recommend the 3x3 mod and the JD kit instead of just going up 1 size with the main? Also, how much will change my fuel consumption? Thanks a lot for the info Share this post Link to post Share on other sites
npm My Rides (2) Posted April 2, 2010 Would you recommend the 3x3 mod and the JD kit instead of just going up 1 size with the main? Also, how much will change my fuel consumption? Thanks a lot for the info Yes, what you are paying for in the kit is a better shaped needle. The 3x3 lets more air in so you must rejet. Fuel consumption doesn't change much but people see a loss in mileage due to the fact that the throttle is so much more fun to use and most end up turning it farther and holding it longer; reducing mileage. Share this post Link to post Share on other sites
