Rotax DD2 xs carb jetting

Hi i know not many people have them but worth a try, i have a pre evo dd2 and have bought new xs carb , however i cant find any jetting charts , i have got an android app but it seem to give very lean results. I am in ambient temperature of 30c with 1015 and 70% . I have a 145 at present but can’t find any info online . Dose any one have any evo jetting info please.

Should be around 132 on evo carb
This is the android app I have used for years.
The rotax one is too rich.Screenshot_20180604-085007_Google%20Play%20Store

Hope the pic worked.

There is an evo and non-evo app.

I have a few apps but seems very lean , but i guess thats how thus carb works, i have to cheak whats in carb will report back after weekend. Thanks

The evo carb runs a much smaller jet, perhaps due to a change in the needle profile.

the carb looks the same form the outside and that is it.
completely different plumbing inside. emulsion tubes and idle jets (progression port) jets are all different.

The main jet is only part of the enrichment system.

Hi
I have also a DD2 Evo and I’m using the same app on my iPhone. In fact, we are several using this app
It’s very theoretical but it’s pretty accurate. It’s a good start for finding the correct setting
It’s also depend of your engine and your carb.
But for me, for example, the last I used it, the app was telling me 132. After different test, the best jetting for me was 130, and the needle on P2 (but that one depend a lot of your racetrack)
One of my friend have the same exact DD2 Evo, same years and for him, his engine work better on 132…

But, this app is working pretty fine and help us a lot

One last thing. You need to be sure everything is matching to the setting of the app. For me, I realize I had a needle for DD2 no EVO… (which is bigger or smaller, can’t remember). And nothing was working properly. After I changed the needle by the correct one (for my carb, EVO), the engine was much better

Just realised what you said about the needle, i had 142 jet and was great, i put 134 and was bogging down in corners , now thinking if i ever changed needle will cheak at weekend but that makes sense. Do you know the numbers for the different needles please.

That exactly the problem I had. Bogging down in corner
The problem is I’m French
May be the name and reference number are different from USA
Anyway
http://www.itakashop.com/fr/1178-carburateur-pompe-a-essence-rotax-125-dd2-evo
Item 3.
Needle K57 (which is matching with the one I have in the app setting)

Hope it will help

One last thing I have done
Even it was working fine, I change all the gasket /seal (not sure of the English name) of my fuel pump (item 44)
That change a lot in my carb

Merci beaucoup , do they have a lot of dd2 in france ?

Sorry
I didn’t saw your question
There was but Rotax is losing a lot of “market” and IAME is having a aggressive attitude to gain market
There is almost no more race for Rotax Max, depend of which part of France you are racing (nothing at the south and more in north of France), even less for DD2.
Even the NSK (national championship, I think last year there was only 10 DD2…)

In my place, there is a lot of DD2… But for people who buy this type of kart just for fun. They don’t want to race, just use it for fun, at the racetrack… That sad

Yes it a shame as its great driving experience without all the pushing that comes with 6 speed, update on bogging down, i don’t think its jet , seems to be fuel supply , has a lot of air and cuts out totally now at end of second straight, we have back to back to back straights. I am putting fuel pump kit in and will try again soon . Will post results , thanks again

We road raced an FR125. Between race maintenance was cleaning the carb, rebuilding the fuel pump, cleaning the power valve and replacing the exhaust packing. Never had engine issues.
Make sure that your pulse line fits tightly on both the crankcase and pump. Also check the float heights.

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