Setting up my carb DR350

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I decided to put a FMF exhaust on the dr350 and also opened up the airbox.
Now every guide i have read online about doing these changes to this bike say's i will need to replace the main jet going from the stock 127.5 to a 140 and raising the needle one notch.
So i did exactly that which did make it run better but i had lots of popping on decel and white deposits plug. (see attached pic)

https://cdn.bikechatforums.com/files/image1248.jpg

So i replaced the 140 main with a 145 which makes it run a lot nicer (more power and less popping) but the plug is still showing white deposits

Bearing in mind almost everyone else with these mods use a 140 with no problems, why is it not enough for my bike ?
Should i just keep on going bigger with the main or should i concentrate more with the pilot and needle ?

Appreciate any info
Thanks
Dave

[robocog]

Original CV carb or pumper?

Only know "a little" about CV's and never had the fortune to own a pumper (yet)
Only knowledge I have is gained from just reading online and put into practice a couple of times which proved on a dyno later that my technique was not 100% - car ran and was "safe" but the AFRs were not ideal nor stable
(I gave up and went EFI)

Plug chop from high RPM and read the plug - this is main jetting
Plug chop from mid rpm for needle height (and shape if there is a choice)
colourtune for around idle
...
Repeat process a coule of times as each "area" overlaps each other to an extent (have a pretty diagram somewhere of a guestimate of what to twiddle at what butterly opening %)

White speccles can also be caused by lots of harsh accel as well from what I have read- best to do plug chops at steady state/loading consistent throttle openings

Why your settings are not 100% smack on the money compared to what others said worked for them ?
IMO Every engine is unique as to what it requires
Just too many variables to be able to quote a number for jet size and how many notches up the needle and how many twiddles of the idle adjuster and assume the fuelling is going to be 100%
Close enough to...
Get it running- more than likely
Safe - maybe
Optimal- never (unless a lucky guess)

Only you can do the final setup
In order of expense
Seat of pants/plug chop/dyno session/wideband lambda and data logging


Regards
Rob
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Needs a bigger garage...

[Livefast123]

Looks like it's running too lean, try a bigger main jet. But as said the other 2 may need adjusting also.
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Current ride - Yamaha MT-07