quick question

[La 450 smoka]

here it is.Mt banshee has a mild port job and 340 dynojet mains.It seems lean because it cuts out bad before powerband,but really takes off when in the powerband.I believe it's lean,huh?Well,I probly need to go up a size or 2,so what is the standard equivalent to a dynojet 340 so I can order 'em?'preciate any help...by the way dynojet needles on 4th position air screw all the way in...starts on first kick even when cold outside..great snappy torque till about 5k, then.... cut out

Edited November 29, 2005 by La 450 smoka

[2003LimitedBanshee]

We need to know a little more about the mods that you have to make sure, elevation, air temp the usual. But from what you described it is a little hard to determine the exact cause of your problem. It could potentially be caused by either a lean or rich condition. However, because it is happening in the midrange, I would try adjusting your needle position before making main jet adjustments since you said it runs great up top. To be safe you could probably raise the needle one position (richer), but my guess is that would be too rich. So my money is on dropping the needle and see if it helps it out. How do the plugs look at WOT?

[Ducman]

Some ported shee's suffer from the dreaded dip in HP that a lot of shee's get at 6K rpm when you look at the dyno Graph, typically get worse the more radical the port is. Read Loco's super long post about jetting the Passion 4mm stroker. Since you said you have mild porting I doubt it is the problem, but its possible. I would determine if the problem is mainly when you are at part throttle like if slowly rolling on the throttle from 1/8 to WOT makes the symptoms worse. If this is the case then you probably need to adjust the needle. Try the (3rd position from the blunt end) middle clip. The dyno jet needle with be richer than the stock needle and the same throttle position due to more taper. I've heard of other people having issues running dynojet needles, personally I'd put the stock needle back in 3rd or 4th clip and see if that cures your problem. I believe dyno jet mains are the same as stock/mikuni mains as far as #'s and flow rate, there probably actually mikuni mains.

[La 450 smoka]

Plugs seem good, and I already tried the 3rd needle position, but I believe the 4th is a LITTLE better.It's really cutting out at every throttle position,

[biggun6ss]

Is it cutting out before the powerband in every gear? I am not sure but if you have the air screw turned all the way in doesn't that mean you could bump up your pilot jet?

[2003LimitedBanshee]

Is it cutting out before the powerband in every gear? I am not sure but if you have the air screw turned all the way in doesn't that mean you could bump up your pilot jet?

443899[/snapback]

 

I don't know how I missed that, but yeah. You shouldn't have your air screw turned all the way in. If it runs the best at this setting then you should bump your pilot jet up, and add a turn and a half or so. But if it runs better with a few turns out on the pilot you have now, well I guess that's self explanatory.

[Banchetta]

Sounds to me that you have a really high rev pipe.. What kind? Porting? Have you tried the stock needles? Compression?

[La 450 smoka]

I don't know how I missed that, but yeah.  You shouldn't have your air screw turned all the way in.  If it runs the best at this setting then you should bump your pilot jet up, and add a turn and a half or so.  But if it runs better with a few turns out on the pilot you have now, well I guess that's self explanatory.

444019[/snapback]

 

 

which 1 is the pilot? The one near the main jet or the one in the back of the carb?

[Banshee~]

which 1 is the pilot? The one near the main jet or the one in the back of the carb?

444883[/snapback]

Leave the pilots alone, they are just fine. The guy at Sandtrax in Tulsa OK, said that hes never had to change a pilot with the dynojet jet kit (even with mild port). Your problem is the main jet. Order some 350-370 main jets and you will be good to go.

[23champ]

Dynojet mains are just mikuni mains. I dont know how you got 340's to work with the dynojet needles tho. The kit comes with 260's and 280's (I think).

 

I used to run 340 mains with the stock needles and needle in the richest postion. Still couldnt get it rich enough on the needle. It cut out and hesitated before it would come up on the pipe. I bought the dynojet kit, installed the needle clip all the way down (richest spot) and put the 280 mains in, and it ran awsome everywhere.

[wesw]

you might try raise the needle to the 5th clip sounds likeyour bike is wanting fuel.

 

also you might try a 27.5 pilot and see how it runs. usually the stock pilot will work but your motor soundslike it wants fuel.

 

basically i would try a 27.5 pilot, 5th clip and 340 and see how the mains look and how the bike acts. youmight have to go up or down onthe mains.

 

best of luck

 

one more thing you should back the air screw out 1/2 turn and she how the bike revs up. it is slow reacting turn it out 1/4 turns - 1/2 till it revs better.

Edited December 5, 2005 by wesw

[Banshee~]

Dynojet mains are just mikuni mains.  I dont know how you got 340's to work with the dynojet needles tho. The kit comes with 260's and 280's (I think).

 

I used to run  340 mains with the stock needles and needle in the richest postion. Still couldnt get it rich enough on the needle.  It cut out and hesitated before it would come up on the pipe. I bought the dynojet kit, installed the needle clip all the way down (richest spot) and put the 280 mains in, and it ran awsome everywhere.

444997[/snapback]

I have the dynojet needles and 340 mains in and it runs perfect with my mods (look in sig) with 40 degree weather, 1000ft. elevation, and outerwares on the k&n's. When it was in the 70's it would bog with the outerwares on. Try the dynojet needle on the 4th clip (from the blunt end) and 360 main jets.

[midnite]

Dyno jet mains are not mikuni mains. Mikuni jets are sized by how many cc's they flow per minute [a 340 mikuni main flows 340 cc's of gas per minute]. Dyno jet mains are sized by the hole in them [340 dj main has a .340mm hole]. The mikuni main jets have the hole chamfered [spelling] on the inside, dyno jet mains are flat on the inside. A 340 mikuni main jet flows more gas than a 340 dyno jet main jet. The dj needles are richer than the stock mikuni needles, but you can get richer needles from mikuni for cheap. Personally, I see no reason to use a $70 jet kit, which only has 2 sizes of main jets in them.

Edited December 7, 2005 by midnite

[Banshee~]

Dyno jet mains are not mikuni mains. Mikuni jets are sized by how many cc's they flow per minute [a 340 mikuni main flows 340 cc's of gas per minute]. Dyno jet mains are sized by the hole in them [340 dj main has a .340mm hole]. The mikuni main jets have the hole  chamfered [spelling]  on the inside, dyno jet mains are flat on the inside.  A 340 mikuni main jet flows more gas than a 340 dyno jet main jet. The dj needles are richer than the stock mikuni needles, but you can get richer needles from mikuni for cheap. Personally, I see no reason to use a $70 jet kit, which only has 2 sizes of main jets in them.

446135[/snapback]

chamfer- to cut a furrow in (as a column) : GROOVE

 

I have a mikuni 270 and a dynojet 270 main jet and they both look the same inside. A guy at a well know shop in Tulsa, OK (sandtrax) said that they flow the same. The reason for the jet kit is for people that want the jetting right the first time and dont want to experiment with different needles.

[midnite]

Set a dj and a mikuni main jet on a table, thread side up and look in the jet with a light and a magnifing glass. The dj jet is flat. The mikuni jet is beveled around the edge of the hole. The jet kit works fine {and is expensive as hell} if your banshee needs 270 or 340 main jets. What if your banshee needs 300, 320, or 360 main jets? dynojet vs mikuni