Bill Blue 340kit coming in a week or so!!!! My bike's in pieces in the garage waiting.. : ) I went 340 for 2 reasons: I figure if I ever need to refresh my cyl, I can bore it up to 351 and be done with it. and: I just like how KLX340 sounds. : ) I like to be a bit different I guess.. Now that I've been waiting I wish I went 351 - he had one in stock!

Turns out Ill have half a point less compression than the 351 also.. might be nice if I put the kickstart in?.. whoknows
~Steve

 

Revtor .. where are you in Northern NJ ... I'm out in Susses by Lake Hopatcong.

Mike

 

Im right on the NY border, Mahwah. I plan on getting down to the pine barrens a few times this summer, ill let the board know!

 

Got my big bore done! Have only got to ride a little on the way home. Oh yeah!
Still got to get the carb dialed in but I can really feel the difference down low.
Here are the pics the guy took for me....











All back together
When I got home my fork springs were waiting for me on the porch! Tomorrow after work I'll try to get em installed! Woo Hoo!

 

Thanks for the pictorial.

Nice, now I gotta save some dinero/look for aluminum cans....

man thats sweet

 

Now to just the the carb dialed in until i can afford a pumper!
Today when I get home from work I'm gonna install my new fork springs.

 

I need some help please from someone who has done the CPR 331 big bore. I dropped off my 2009 klx250s and had them do it for me since its their business. Picked the bike up 1 week later to find that its got A LOT more power. the front wheel does not want to stay on the ground, that's for sure. Looking forward to some good trail riding to really get on it..

Ok, so here is the question/issue: When i release the throttle after a fast acceleration and just use engine braking to slow down i get HORRIBLE loud popping coming out of the exhaust. This continues until i either give it a little throttle or i come to a stop. CPR told me to open up the fuel screw. I did that and it did not fix the issue. Then they told me to close down the fuel screw. did that and no help. CPR then said the packing could be shot in my full muzzy. Checked it, perfect condition. Then they told me to check the header and make sure it was tight. Again, done and all perfect. Now they tell me to get it rejetted. That is the issue. I spent a lot of time and money getting the bike to them to complete the job for me. I live out in Long Island and drove over 2 hours each way and more tolls then i can count.

So, what size jet IS needed for this mod to be complete? I have no idea what size jet they installed when they did the bike so I am at a loss here.

I was also told that the popping is not bad for the bike in anyway; however, it is terrible for the people around me including myself as the popping is SOOOOO LOUD.

I am not confident changing the jet needle myself, unless someone here can advise me on the ease of doing it. And spending MORE money to complete this mod does not seem too fair (paying someone locally or driving another 5 hours RT to get it done by CPR).

Thanks in advance.

 

Hey tmoe nice pics! I am glad they took them for you and that you posted them for us!!! I can't wait to get a big bore!

cosmickites...Just a thought...didi you take the smog stuff off your bike? If you did check to make sure your plugs are still good and sealed...had to redo mine on the front of the motor...I used some hi-temp silicone and it helped...Like I said just an idea...if you are sucking in air it will cause a decel pop...Good luck and hope this helps!

 

So what's the theory? Rich/Lean? Mine does this a bit more now that I went Big Bore and raised my needle one clip (richer)... I'm going to lower my needle two clips and see the popping reduces.

Have you checked your plug to see if tis rich/lean? I think they call it a "Plug Chop" search that and give it a shot. if its rich, adjust leaner, if its lean, adjust richer. Don't be afraid to get into things, just take your time and keep carb parts clean. Work on a clean towel at a bench.

 

When using the engine compression for braking, the throttle plate is closed. That puts the carb into the pilot circuit....pilot jet and pilot screw. Popping on deceleration is usually from a lean mixture and occasionally from a leak where the head pipe meets the head.
The carb needle shouldn't be your problem.........I see that you have already installed a DJ kit.

Make sure that you don't have a small air leak between the carb and the intake manifold.
With the engine warmed up, adjust the pilot screw for the fastest idle. If it takes more than three turns out, increase the pilot jet size by one step. The pilot screw and pilot jet run parallel.

Hope that helps.

Ride on
Brewster