"08" EC125 Cylinder Pressure

[kevells]

Hi
I wonder if someone could tell me what pressure you would expect on a EC125, I have carried out a compression test earlier which gave 165psi with the throttle fully open is this a little low.
The reason for carrying out the test is the bike does not pull cleanly low down, feels as if you are riding with the choke on, but fine in the higher revs. I have checked the main jet, slide, needle etc which are what Gas Gas UK recommend for the UK. I have noticed that it does not have the airbox restrictor plate which should be fitted!

Any comments would be greatly appreciated

Thanks

Kevin

 

[roostafish]

165 sounds a little low. Try it again with a few cc's of oil. I'm expecting a little higher number. Could be reeds if you have not checked them.

 

[GMP]

Thats a single ring piston, so if you don't kick it fast enough you won't get a good reading as there is more leakage. I tend to think you have a jetting or reed problem. From my experience, at least in the US, the stock jetting was crap. The bike is sensitive, and the low end is poor if its not jetted right. I think this is a big part of why the bike gets a bad rap for poor low end performance. I'd like to try a 36mm carb on ours.

 

[Luke811]

how do you measure?

LuKe(noob)

 

[roostafish]

A smaller carb will surely improve low end performance, and will not hurt the top end either. I once put a 38mm carb on a KTM 125. Mistake, I went back to stock and was much happier. I think that carb was a 35mm DelOrto.

If the bike was acceptable before, and is now hurting in performance, try the reeds.


Luke:
The compression is checked by using a compression tester screwed in to the sparking plug hole. You then give rapid kicks until a maximum number is achieved on the guage.

 

[Luke811]

Luke:
The compression is checked by using a compression tester screwed in to the sparking plug hole. You then give rapid kicks until a maximum number is achieved on the guage.

Ok thanks,here isn't a practice widely used

For Kevells:carb settings?

a 36 keihin could help with low-med rpm...on 2011 has been developed for this

LuKe

 

[kevells]

Thank you for the replies so far, in answer to some of the questionsyou have raised, since owning the bike (about 3 months) it has always been the same in the lower rev range, does not pull at all in 1st &2nd gear (just like ridding with the choke on/mixture too rich!) I have had the reed block (V Force 3)out last night, they all seem to be sitting flat on their seats with no damage to the reeds!

The carb is a stock Keihin 38mm PWK
Main Jet 180
Slow Jet 48
Needle - NOZI set in middle position (have also tried in lowest notch)
Slide - G
Air Screw 11/2 turns out

Having spoken to Gas Gas uk the above is what they would recommend!
In the parts manual it shows a restrictor plate in the airbox for the 125 & 200, but mine does'nt have one - could this make the difference?

 

[Luke811]

Thank you for the replies so far, in answer to some of the questionsyou have raised, since owning the bike (about 3 months) it has always been the same in the lower rev range, does not pull at all in 1st &2nd gear (just like ridding with the choke on/mixture too rich!) I have had the reed block (V Force 3)out last night, they all seem to be sitting flat on their seats with no damage to the reeds!

The carb is a stock Keihin 38mm PWK
Main Jet 180
Slow Jet 48
Needle - NOZI set in middle position (have also tried in lowest notch)
Slide - G
Air Screw 11/2 turns out

Having spoken to Gas Gas uk the above is what they would recommend!
In the parts manual it shows a restrictor plate in the airbox for the 125 & 200, but mine does'nt have one - could this make the difference?

i think that the restrictor plate is that for the road version,because also mine GG 125 hasn't got...if I understand what you mean for "restrictor plate"

...and if it was useful http://www.facebook.com/pages/Gas-G...otos#!/album.php?aid=52484&id=150354918326940



Luke