GG EC 300 '01 - Rebuild // Powervalve problem

[Hugo4x4]

Hello everyone!

I have bought an EC 300 '01 model with an all new motor (oem parts), but the problem is that the power valves aren't opening, i disassembled the exhaust and the cilinder covers and the valves really seem to work ok with my finger..

Any common problem with this machines? Have to open the engine?

The bike has tons of bottom power, engine runs nice and without any weird engine noise..

 

[Jakobi]

What have you done to confirm the PV isn't opening?

You can run the engine with the rhs (exhaust side) PV cover off and watch the plate move through its range.

It's a simple setup. Centrifugal force governor, few linkages and then the actuator arm and plate that comes up through the cylinder.

The bearings, drum valves, and flapper are pretty straight forward, but can bind a bit if too much carbon is built up on them.

 

[webmaster]

Look on the main page of this website under articles for instructions on pv assembly if you want to verify your work

Jeff

 

[Hugo4x4]

What have you done to confirm the PV isn't opening?

You can run the engine with the rhs (exhaust side) PV cover off and watch the plate move through its range.

It's a simple setup. Centrifugal force governor, few linkages and then the actuator arm and plate that comes up through the cylinder.

The bearings, drum valves, and flapper are pretty straight forward, but can bind a bit if too much carbon is built up on them.

First of all, thanks for the reply!

I dont feel the "kick" of the power valve opening, in 5ft and 6th gear at high rpm the bike feels like an 125cc..

I removed both covers and it doesn't have much carbon, most of it is oil and seems ok. Thought it could have a common problem or somethink like that..

 

[Zman]

After you removed the covers, did you run the engine to confirm the PV opens as the engine revs? If it does open, you should check float level and jetting.

 

[Jakobi]

After you removed the covers, did you run the engine to confirm the PV opens as the engine revs? If it does open, you should check float level and jetting.

What were the early models like?? Did they tend to sign off a bit up top as well?

As above. You need to check the powervalve is operating under throttle with the bike on the stand and the cover off. That will confirm if the PV is opening. Many have had issues with the pole on the actuator plate breaking and while the arm moves, it does not drive the plate around to open the PV.

If you dislodged a ball bearing in the governor or the assembly is binding you'll typically hear the mechanical struggles. It doesn't sound nice.

Also, sounding/feeling like a 125 can be a result of being too lean. Lacking balls and sounding tinny, with flat uninspiring pull. Usually it's being flat across the bottom to mid that people report as feeling like a 125 though.. weak off the bottom with a more pronounced hit in the mid.

 

[Zman]

What were the early models like?? Did they tend to sign off a bit up top as well?

My 2000 XC300 had the old brick style CDI that limited high RPM capability compared to the 2010 dual map version that replace it. I think I picked up about 500 to 700rpm compared to the brick CDI. I am not sure if my old CDI was degraded from age or if it just had a different map. Even with the old brick my 300 big bore still ran up to 8000 to 8500.