Two simple carb part questions

[avizpls]

Oh yeah it does. Ive been dealing with this throttle hesitation since the build though, so Im only now REALLY experiencing the new motor.

Hey, I couldn't find the recommended settings based on modifications made. Do you happen to remember where exactly?

[koko64]

This kit is for Euro models E7206.001 so is a little different but is for "open air box with K&N filter, mild tune, aftermarket exhaust". Your DJ 175 jets are about the same as Mikuni 165ish.

EDIT: I checked out the US version of the kit and it recommends notch 5 out of 6. So you may need notch 6 out of 7!

The needle pos-n recommended is #3 from the top out of 6 notches. Make that 5 out of 6 notches. The needles are DNT730 ones. I think that your needle is set too lean as it would correspond to the first notch on the newer needles. My 7 notch needle was the same but for the extra notch. The taper appeared the same as did the length. If your needle is an old 729 it would be leaner in taper still. I think that some US models came with it but can't for sure remember. With this in mind I am not suprised that you have a lean hesitation. Your second notch pos-n is the leanest pos-n on the new generation needles. That will not help acceleration.

EDIT: The US stage 2 needles are 730 ones like mine.

Set the needle on the 6th notch and try it (6th from top). This corresponds to the 5th notch on the newer needles. I ran even higher needle pos-ns but my bike has significant porting on the inlet side. Test it with 50mph roll ons in 4th and 5th gear and see if acceleration improves.

Now I maniacally went through trying each needle pos-n with 50mph roll ons and 50mph cruising untill I was satisfied. I richened the needle (raising it) untill I was happy I had good acceleration, but I also made sure this did not cause rich burbling/missing at steady cruising which means you have gone too far and have to bring it back a notch. I don't recommend doing this as you can go mad! And get a ticket or crash. Dynos are a Godsend!

Check out the Factory Pro and Dynojet sites for tuning tips from experts and not backyard bums like me. I'd pop over with a few beers to help you out but I'm too far away!

Keep in mind that the stock carbs are a compromise and you need to settle for a balance between all out balls out acceleration which requires a lot of fuel suddenly squirted into the carb and a decently smooth steady cruising with reasonable economy between 45 and 70mph. They are not a flat slide carb with an accelerator pump which is a fuel 'water pistol' like device that will give extra fuel when you suddenly crank the throttle open. Stock carbs don't have them so dont expect instantaneous acceleration. Respect the carb for what it is and feed it in with a quick roll on rather than snapping it open.

An old bike tuner once advised me to "ride the carb".

[koko64]

I looked up the Dynojet site for a US stage 2 kit.

Ok the wash up of all that is try needle notch #6 from the top. If it causes rich burbling at steady cruising speeds then try #5. You should be close. I ran the same 175 DJ main jets with an open air box and aftermarket pipes which Dynojet also recommended. The Idle Mixture Screw setting suggested was 2 and a half turns out from lightly seated. As a rule, the fastest, strongest idle speed will tell you the correct number of turns (with a well warmed up motor).

Sorry for the confusion between Euro and US versions of the Stage 2 kit. We get the Euro kits in Australia.

Tell us how you go with it.

Now a question for everyone, is it different fuel or different calibration of internal drillways, that results in the different needle positions recommended by Dynojet for the same needle (DNT730) on US and Euro spec bikes. I reckon our fuel is different but I've been told that US carbs are slightly different internally.

[avizpls]

Excellent, thank you. Right now I am on position 4 of my 7 (like 5/6 on the new ones). Im saving all of the info here thanks!