Please clarify these GasGas engine truths.

[Mazikeen]

make me feel better?

The EC300 engine can rattle just off idle, it is usually a power valve and favors a specific RPM unique to each engine depending on whether the pv arm is adjusted correctly. This noise can lead a person not used to it to compare it to a rod bearing type noise.

EC300 gearboxs are freakin loud, if the clutch is pulled in, everything is warm and fuzzy, if the clutch is released in neutral instantly a whirr/growl will occur, again, this is the nature of the beast, not a bad trans bearing, some motors and worse, some nearly quiet.

These noises aggravated the snot out of me today, off idle putting through the parking lot at the local track was literally embarrasing, well the knock noise, the trans noise you have to be more attentive to. The bike in question here is a 2011 ISDE 300, but the forums here seem to indicate these "unique" characteristics date back many years.

 

[noobi]

make me feel better?

The EC300 engine can rattle just off idle, it is usually a power valve and favors a specific RPM unique to each engine depending on whether the pv arm is adjusted correctly. This noise can lead a person not used to it to compare it to a rod bearing type noise.

EC300 gearboxs are freakin loud, if the clutch is pulled in, everything is warm and fuzzy, if the clutch is released in neutral instantly a whirr/growl will occur, again, this is the nature of the beast, not a bad trans bearing, some motors and worse, some nearly quiet.

These noises aggravated the snot out of me today, off idle putting through the parking lot at the local track was literally embarrasing, well the knock noise, the trans noise you have to be more attentive to. The bike in question here is a 2011 ISDE 300, but the forums here seem to indicate these "unique" characteristics date back many years.

Yes, both are true.
The PV more often than not is not set correctly from factory and usually has some free play, and because its not tensioned to anything until the PV starts to open, it can rattle. Theres a few threads around about adjusting the free play out.

The clutch is pretty noisy yes, but compared to other 2 strokes iv heard, it doesn't seem to be any worse? Maybe pull the clutch cover and see if theres any play in the clutch assembly. How often do you change the oil?

 

[Jakobi]

Yep yep and yep!

All normal. The clutch thing I only really notice if I'm looking for it. The powervalve will clack as described above. I don't think its loud enough that anyone else could hear it though.

If the pipes not alligned properly or rubs against the exhaust flange bolts a bit you will get a horrible vibrating rattle at certain rpms too. I've also heard that the springs can sometimes vibe against the pipe.

 

[Mattnzl]

Phew, I definately had some "clacking" on my ride on Saturday and was hoping it was a PV. Comming from a KDX I'm used to noisy PV's, but the KDX does it most at idle and quietens up with more revs.
My EC seems to do it sometimes if I come out of a corner in a higher than optimal gear and just let it lug back up to speed.

 

[Jakobi]

Phew, I definately had some "clacking" on my ride on Saturday and was hoping it was a PV. Comming from a KDX I'm used to noisy PV's, but the KDX does it most at idle and quietens up with more revs.
My EC seems to do it sometimes if I come out of a corner in a higher than optimal gear and just let it lug back up to speed.

Matt,

This sounds a lot like chain slap to me mate. Chain slapping against the swing arm. If you've every rode a Yamaha WR250/450 you should know it well. I can make my gasser do it when loading the bike in a high gear. Its to do with the power pulses on the chain through the sprockets. Sometimes tightening the chain a tad more will quiet things up. Don't go too tight though.

 

[hannesd]

Yes, both are true.
The PV more often than not is not set correctly from factory and usually has some free play, and because its not tensioned to anything until the PV starts to open, it can rattle. Theres a few threads around about adjusting the free play out.

The clutch is pretty noisy yes, but compared to other 2 strokes iv heard, it doesn't seem to be any worse? Maybe pull the clutch cover and see if theres any play in the clutch assembly. How often do you change the oil?

this feels good to hear from other riders having the same "issues".
i was about to rebuild it, could be time too to get it done, but it makes me wanna hold it off since i wanna ride and ride
idle has never been super though.
can too much compression have something to doo with that?
i put a new topend last year and measured compression with a meter maybe not so accurate...i got over 200psi
my idle is not a nice "ding ding ding" but runs "looser then what you'd expect with such compression. got a 0.3mm base gasket installed.

sorry to go off topic here...

hannes.

 

[Jakobi]

The idle is more likely a jetting issue. They can be somewhat finicky to tune around this area.

Pleanty of info in threads regarding how to set the preload tension for the PV, tuning, carbs, etc. Do a quick search and you'll likely find its been covered already.

 

[GasGas]

The motor will sound like it's about to let go when the exhaust flange o-rings are worn out too.

 

[Mazikeen]

jocabi/gasgas mentioned another item that did not come out in my forum search, exhaust flange rattle.

Obviously I'll be taking it apart, but I noticed this morning (I just had to fiddle with it, this rattle is bad) if I load the pipe to the right the noise stops. I can easily duplicate the noise it is continual at "x" rpm. So I am thinking that my rattle is not the pv valve as this is very loud and I see no reason a pv rattle would abate by pushing on the pipe. I find no dents, twinks or the like over the pipe, springs are good, no leaks, but perhaps the orings are wearing but not enough to leak yet.

I change my oil every 8ish hours of riding.

 

[GasGas]

My pipe rattled most prominently on deceleration.

 

[Jakobi]

I find the same as GasGas. Say riding in 3rd gear and giving it the throttle its fine, its when I unload the engine and allow the revs to fall as it comes through the certain rev range theres a very loud brrrrrrrrrr metal on metal vibration. Dropping the revs lower fixes it, picking them higher fixes it too.

The stock o-rings I believe are just plain rubber and once they get a flat spot they will vibe. Get some Viton ones to replace them with. Have a good look at the pipe for signs of wear when its off. Make sure all the pipe mounts are set up for the best position, and I have also found a generous amount of high temp silicone will assist with keeping a good seal with less vibes.

 

[andoman]

Viton Cross-Over?

The stock o-rings I believe are just plain rubber and once they get a flat spot they will vibe. Get some Viton ones to replace them with.

Are the o-rings from the late model CR-250 on the parts cross-over list viton?

 

[Jakobi]

Are the o-rings from the late model CR-250 on the parts cross-over list viton?

Don't know but the CR250 ones are well over priced! Hit the local bearing shop and just ask for Viton o-rings. Can't remember the right size off the top of my head but a quick search of the forum will turn it up.

 

[hannesd]

Don't know but the CR250 ones are well over priced! Hit the local bearing shop and just ask for Viton o-rings. Can't remember the right size off the top of my head but a quick search of the forum will turn it up.

43x3mm if i'm not mistaken
got mine dirt cheap at the local orange dealer

 

[Mazikeen]

43x3mm if i'm not mistaken
got mine dirt cheap at the local orange dealer

Is this a good size? I've been searching and was about to order some on line just to get a good measurement. I'm going to put new ones in but wanted to order some Markez or Kalrez as they have about 100f+ more temp potential and nearly no compression memory, viton if I recall is like 50% these are more like under 20%, between the higher temp potential and the memory, they might have a significant life improvement.

 

[andoman]

43x3mm if i'm not mistaken
got mine dirt cheap at the local orange dealer

The "orange" ones are 44X3mm and are viton. $4 bucks ea. So, it looks like they will work just fine. The extra 1mm length shouldn't be an issue and the extra material will add to the sealing properties.

Thanks!

EDIT: Research online outside of this site indicates that the GG o-rings are in fact 44X3mm. So the "orange" bike viton ones are indeed a direct cross-over.

 

[Warwick Simpson]

Because I had one a Moto Guzzi flange gasket from a 4 valve engine placed inside the flange fixed mine. Done 150 hrs with no rattles on original O rings.

 

[Mazikeen]

Interesting, any part numbers/pictures that would allow us to research/find these?

 

[flybars]

I recently purchased a pack of 10 Viton O-rings at McMaster-Carr. I think it was around $15.00? They shipped them to me very fast I remember. Size-
44mm ID x 3mm. I ordered over the phone at 562-692-5911. Their website is mcmaster.com.
I also used Permatex High Temp RTV Silicone and followed fmf's install advice by gooping the inside of header pipe flange and used the exhaust springs to pull the pipe on. Man what a difference it made in sound. I only found one piece of o-ring when I pulled the pipe off, so I should get some good power gains too. I busted up my ribs recently on a Mojave desert ride so it will be a while before I can test.

 

[Mazikeen]

Grainger has a pack of 25 for $22.50, in stock for p/u at my local branch, part #1kag2, viton. I wanted to go kalrez or such, but they'll run me $35 a piece which is assinine. hadn't had a chance/day off! to get down to grainger yet so the guzzi flange interested me.