EC300 Jetting Help

Hicksi

New member
Hey Guys,

As of recent, the EC300 has undergone an SM conversion.

In the process I've changed the gearing and added a pipe system.

The bike is 2001 and is ridden in the UK, under 55 degrees F, and around 0-2500ft. The front drive sprocket is OEM still, and the rear is a 41 tooth. I weigh about 80kg.

Should i be changing my Jetting set up? I would like the bike to run a little crisper with the new pipe system.

Anyone got any suggestions as to what set up i should use? And what parts i actually need to buy and replace?

Thanks for the help in advance.
 
I think it would help to know a little more before suggesting what to change.

What fuel are you using - unleaded or super unleaded?
What fuel / oil mix are you using?
What are the settings / jetting at the moment?

I ride in UK with a 06 EC300:-
Super unleaded fuel
50 to 1 fuel with rock oil synthetic
175 main jet
40 pilot
CCK needle.

Carb spares in the UK are easy to get mail order from Allens R&D http://www.allensperformance.co.uk/
 
Should i be changing my Jetting set up? I would like the bike to run a little crisper with the new pipe system.

What do you expect us to tell you?? How does it run now and what jetting is in it currently?
 
Apologies for being impatient.

Im currently rebuilding the bike, and get frustrated when i have to stop (only because im unsure of jetting myself...)

The jetting is currently in stock trim. I tried to source some details on what the standard set up is, but to no avail.

I have rebuilt the bike as a supermoto. So previously when going off road, short blasts on the throttle were fine, but now on road conditions with constant throttle positions rather than blasts, its 'stuttery'. (I hope that makes sense).

Im currently using normal unleaded.

The oil ratio is a 50:1 (using Castrol Power 1 oil).

As above, the jetting is as standard.

Now that i have rebuilt the bike as a supermoto, i've obviously changed the wheel size (17") and the gearing. Stock front sprocket, and a 41 rear. I've also added a full DEP system.

Todd5774 - thanks for the setup, how does the bike ride compared to stock?

Wasp4banger - are you running a performance exhaust?

Thanks guys
 
Open the carb up. It'll take you all of 10 minutes to report your pilot, needle, and main..

Its still a raw 2 stroke at heart and will never really feel nice whiel running at part throttle. They like to be accellerating.

What changes have you done to the drive line? Cush drive etc? Without it will be pretty snatchy on the road also.
 
Apologies for being impatient.

Im currently rebuilding the bike, and get frustrated when i have to stop (only because im unsure of jetting myself...)

The jetting is currently in stock trim. I tried to source some details on what the standard set up is, but to no avail.

I have rebuilt the bike as a supermoto. So previously when going off road, short blasts on the throttle were fine, but now on road conditions with constant throttle positions rather than blasts, its 'stuttery'. (I hope that makes sense).

Im currently using normal unleaded.

The oil ratio is a 50:1 (using Castrol Power 1 oil).

As above, the jetting is as standard.

Now that i have rebuilt the bike as a supermoto, i've obviously changed the wheel size (17") and the gearing. Stock front sprocket, and a 41 rear. I've also added a full DEP system.

Todd5774 - thanks for the setup, how does the bike ride compared to stock?

Wasp4banger - are you running a performance exhaust?

Thanks guys
The pipe I run is stock and the only mods I have done other than jetting are to improve the bottom end response (I ride mainly twisty/tight trails).

To do this I've added a large volume power valve cover and modified the squish (the cheap way) by reducing the base gasket thickness. Look elsewhere on here for squish to see how you might improve this. Lots here rate the RB head mod, but he's the other side of the world from me!

My guess from what you have described is that your bike may be rich on the main jet?
 
178 main
40 pilot
JD red needle on clip 3

Also was running a full Dep system bikes an 02

I do know, this thread is 3 years old, but its still an active topic of many.

For SM jetting, this should not be 175/40. Rather more like 180-184/38-45 (main/pilot) (running 1,2 squish,8plug, 250m over sea, 12-25celcius. humidity unknown,

Running 178 is pretty lean on abusing on the street.
 
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