Making my EC250 more like an MC

[GG27]

I was thinking of an easy way of increasing the low end power on my EC250 is by changing over the jetting, silencer and CDI from an MC. Currently it runs very weak but smooth on the bottom and strong mid to top. I have to clutch it through slow turns to keep it on the mid-upper meat of the power band.

I know I can increase the compression by removing the gaskets and fixing the squish band but I don't want to open up the engine yet.

In what order will these changes increase my low end and by how much, if any?

I have ordered the LTR jetting kit and PV cover just to get that extra bottom.

Thanks

 

[Loosenut]

The low-end will not be able to match the MC until you have head work done. It's cheap and easy, so why fight it.

 

[widebear]

changing to the lighter mc stator/rotar combo will make a huge differance

 

[GG27]

I guess I'll change the base gaskets to one .3mm and shave the head by another .5 mm to increase the compression, since there is no reputable machine shop here in Athens to correct the dome shape and height.

BTW I looked up the parts catalog from the factory sight for the 2008 models and the MC head has a completely different part number. Should I just order that instead and check the squish with that head?

I'll also check the price for the lighter DE ignition-flywheel combo. Won;t I have to get an extra FWW for tight woods riding?


Thanks

 

[widebear]

All depends how deft you are with your right hand, now the only time i use the 3k ign is for night racing, gasgas has such sweet power delivery i.m.o. flywheel weight is not required

 

[GMP]

I'm surprised, I think the low end on my '07 is pretty damn good. There are a lot of things you can do, but try some jetting changes first.

 

[GG27]

GMP,

I think you guys in the states have the lighter ignition coil. Hence the better low end.

 

[iancp5]

GMP,

I think you guys in the states have the lighter ignition coil. Hence the better low end.

How does that make it a better low end? Surely it just revs quicker?
Or from my perspective just stalls quicker

 

[GMP]

The flywheel has nothing to do with torque, it just dampens changes in RPM. If its snap your looking for than yes, the 2K-2 helps with that. I can see where finding more off idle torque by other means will help the bigger flywheel spin up a bit quicker. I like the lighter 2K-2 ignition with a small weight and G2 throttle, 200 cam.

 

[GG27]

GMP

What other means do you suggest apart from LT jet, PV cover and base gasket- head shave? I have already ordered the jet kit and PV cover and I hope they will help the low down torque of this otherwise fantastic bike. I have geared down to 13/50 also.

 

[PEB]

If it has it take out the reed spacer.

Paul B

 

[Leon_gasgas]

Something is very wrong with your jetting. My 07 pulls great from 0 rpm all the way up. Still I don't agree having the eg or ef clip in 2nd position. Then the bike is lean and weak (especially under load). My stock EC250 gasgas has better real torque than the torque monster by the mags KLX450R (I had it for 2 months, rejetted it, and even went with a 2 teeth larger rear sprocket)! It pulls with third easily out of almost any turn, ok with some clutch help sometimes (catched myself sometimes going to 2nd but that made the bike strange... if you understand what I want to say). I owned an MC250 2005 (and dislocated my shoulder with that on a wet enduro trail) and I think the heavier EC ignition is much better for enduro than the MC ignition. If you are going to avoid enduro paths and concetrate on cross country or MX then go for the lighter ignition. But then it might be altogether better to own a new YZ250...

 

[Hollywood]

Something is very wrong with your jetting. My 07 pulls great from 0 rpm all the way up. Still I don't agree having the eg or ef clip in 2nd position. Then the bike is lean and weak (especially under load). My stock EC250 gasgas has better real torque than the torque monster by the mags KLX450R (I had it for 2 months, rejetted it, and even went with a 2 teeth larger rear sprocket)! It pulls with third easily out of almost any turn, ok with some clutch help sometimes (catched myself sometimes going to 2nd but that made the bike strange... if you understand what I want to say). I owned an MC250 2005 (and dislocated my shoulder with that on a wet enduro trail) and I think the heavier EC ignition is much better for enduro than the MC ignition. If you are going to avoid enduro paths and concetrate on cross country or MX then go for the lighter ignition. But then it might be altogether better to own a new YZ250...

Yup, the yz250 is a godly machine, the best 250 ever made.

 

[GG27]

O.K. After reading all the sites and posts and after playing with the jetting I had come to the following settings:

175 mj
40 pj
N1EF 3rd

The bike was working fine apart from a weak low end, so I thought of checking the float since there was allot of dampness around the bowl and air screw area.

I took my carburetor out and checked the float height. It was 15mm! That is why my bike was running rich on the bottom and I was trying to fix it by making the pilot leaner and lowering the needle. I set the float height to 16.5mm and put in a 42 pilot. I then tried the 1369D needle at #3 with a 178 main and the bottom seemed to waken up but was just seemed a little rich with air screw 2 1/2 out.

I also bought the LTR needle and power valve cover, so I tried the needle but with leaner jetting than the suggested 45pj and 180mj (I didn't want to change the pilot, too much hassle) and the bike was very crisp response of the bottom (maybe too crisp) so I replaced it with the 1369D at #2 and placed the PV cover and went to the nearby practice area....Boy the bike really can pull from down low all the way up to the ceiling. I am very please with this setup. Maybe I'll try the LTR needle with the richer pilot to see how she goes.

Talking about the YZ250 I absolutely agree that that motor is the best two stroke motor on the planet but only on a mx track, not on tight trails, it is too snappy, I owed a 2006 model before I got my GG and I had highsided many times coming out of tight turns. It was the perfect adrenaline machine but very tiring for longer rides.

Now my EC250 is really tractable and makes as much power as my YZ just smoother. I don't think I'll need the lighter ignition since I can lug it really low, I can climb hills in a slow third without bogging as before I would go up in second and I can snap the throttle with good response no bogging. Maybe when I open her up for her piston change I'll tighten up the squish with thinner base gaskets.

I'm really greatfull to all you guys on this site that helped sort out these frustrating problems.

 

[GG27]

I also agree with Leon, that for Enduros this motor has the perfect combination of torque and power, helping you go as fast as possible but not tiring at all.

A local rider finished first overall in the local enduro championship race, beating much faster bikes and riders on a EC250 '08 model straight out of the box!

Thank you Leon for your insight and insisting that the jetting was off.

 

[Leon_gasgas]

Hi!

Great to hear that you are sorting out the carb settings. Still I suggest you try a 45 pilot with temps less than 20 C (Check CMP's settings from the database as well) and an 180 main. As a reference, on Saturday with a lot of humidity and rain sometimes and the temp around +5 C my 07 worked great with:

45 pilot, 1 and 1/2 turns out (I know for next winter I will need a 48...),
N1EF #3,
185 main.

Leon

 

[GG27]

I put the LTR needle at #3 and changed the MJ to a 180, weather was in the mid 80's so I let the PJ at 42, air screw 2 1/2 out. Bike runs really crisp and linear , no bogging at all and revs to the moon, no spooge at all.

I ordered an MC250 head (it has a different part number on the parts catalog and is listed for the MC and SM 250's) just to increase the compression without changing the port timing and to get more bottom grunt without loosing the endless revability at top, (I'm still looking for that YZ low end pull).

What do you think?