EC300 still down on power

[19brendan81]

Re pipes - my bike has the nickel plated pipe on it. Does that mean there is no catalytic converter welded inside?

I notice that if you tap my pipe with a spanner, it makes a 'thud thud thud' noise, whereas if you tap the stock pipe on my mates YZ it makes a 'ting ting ting' noise. I had always assumed there was an extra lining inside there.

Re the compression tester - im pretty sure it is accurate. I have used it on other things (cars, other bikes, chainsaws) and it reads as expected. The most recent example of this was when I was rebuilding a Mini 1000 motor and it read 160psi on each cylinder which what I was expecting.

I will test my bike again once I have done the reeds, as if these were leaking (which they are) it would effect compression to a degree...not sure if it would effect it to the extent of losing 40 psi though. If I cant get the compression up...would you say that 120psi is too low? It seems very low to me.

 

[Jakobi]

I've ran with chipped reed petals and it made the bike a pig to idle and a bit crap right off the bottom. I wouldn't say it felt too bad under heavy throttle.

I'd be trying to run a length of wire or the likes through the pipe to see if their is anything in there blocking it. Cat perhaps.

 

[stainlesscycle]

I will test my bike again once I have done the reeds, as if these were leaking (which they are) it would effect compression to a degree...not sure if it would effect it to the extent of losing 40 psi though. If I cant get the compression up...would you say that 120psi is too low? It seems very low to me.

i'm assuming you're kicking it about 5-10 times with wide open throttle?

 

[19brendan81]

Yep. It was taking a good 6 or 8 kicks to get the reading stable, then a few more after that for good measure. I was doing it in sneakers too and my foot was killing me after doing the test 6 times! I had to use lefty for the last one.

 

[(F5)]

I've never heard of a nickel pipe with anything in it but who knows.

Reeds could be missing & you'll get the same com reading at kick over speed.

so without re reading the last 3 pages; when did you last look at the piston & check the rings not worn or snagged over?

 

[19brendan81]

Piston and rings are brand new....have been on 2 approximately 3 hour rides on them. They went in fine and the piston is DEFINITELY installed the correct way - I have done this job before and checked a million times.

 

[noobi]

Cleaned the carb recently? Sounds like a blocked jet, or could be a loose electrical connection somewhere.
For me, one of the female spade connectors on the coil was loose and made my bike run rubbish, squished to a bit and its been fine ever since.

 

[Gasserguy250]

Hi, My EC 250 has the same symptoms, reeding this thread has really helped. I have alot of checks to catch up on. Just wanna say thanks so thanks

 

[Jakobi]

Hi, My EC 250 has the same symptoms, reeding this thread has really helped. I have alot of checks to catch up on. Just wanna say thanks so thanks

Welcome to GGRider.. Hope you enjoy your stay! Pleanty of usefull info here to help you get your Gasser running right.

 

[19brendan81]

The carb has just been rebuilt by RB designs...its definitely not that. The bike had even less power than this (substantially infact) before I did the head, carb and carby.

Is it the compression? What sort of readings have other 300 riders gotten with their compression tests?

"Just wanna say thanks so thanks "

No worries!

 

[19brendan81]

OK - did the reeds, and the bike is still a gutless piece of crap. I am surprised because the old reeds were shot, cracked through in places, not sealing and sitting proud of each other. I thought for sure replacing these would make a difference but it hasnt. So now the bike has...

brand new piston and ring
head machined
brand new reeds
carb bored and jetted by RB
confirmed that the exhaust is clear and free of obstruction.

Some other things I have noticed are...

1) I am picking up what appears to be the bike pinging or detonating under load.
2) The bike has a higher pitched exhaust note than the YZ250, RMX250 and EC300 two strokes that I ride with...more of a buzz than the typcial two stroke roar that im used to.
3) To get the bike to idle - I have had to wind the idle adjuster ALL the way in. It literally can not be wound in any further.

Does anyone have any ideas what it could be besides ignition? I really dont want to drop $300 - $400 on a CDI only to find out its no different. I have inspected the powervalves as per the info on this site, and can confirm they actuate correctly by hand...I cannot confirm that they are opening when the motor is going though as I have never checked.

Desperate to get this fixed or it will be burnt. Any suggestions you can give will be most welcome.

Brendan

 

[Jakobi]

OK - did the reeds, and the bike is still a gutless piece of crap. I am surprised because the old reeds were shot, cracked through in places, not sealing and sitting proud of each other. I thought for sure replacing these would make a difference but it hasnt. So now the bike has...

brand new piston and ring
head machined
brand new reeds
carb bored and jetted by RB
confirmed that the exhaust is clear and free of obstruction.

Some other things I have noticed are...

1) I am picking up what appears to be the bike pinging or detonating under load. LEAN CONDITION
2) The bike has a higher pitched exhaust note than the YZ250, RMX250 and EC300 two strokes that I ride with...more of a buzz than the typcial two stroke roar that im used to. LEAN CONDITION
3) To get the bike to idle - I have had to wind the idle adjuster ALL the way in. It literally can not be wound in any further. RICH CONDITION

Does anyone have any ideas what it could be besides ignition? I really dont want to drop $300 - $400 on a CDI only to find out its no different. I have inspected the powervalves as per the info on this site, and can confirm they actuate correctly by hand...I cannot confirm that they are opening when the motor is going though as I have never checked. Take the time to run the bike with the RHS powervalve cover off and confirm the PV is working with the engine

Desperate to get this fixed or it will be burnt. Any suggestions you can give will be most welcome.

Brendan

I didn't read back over it, but what jetting are you running?
Manipulating the PV actuartor arm manually can cause issues with the governer. Its advisable not to as it may dislodge a ball and stop it working.
On the topic of engine down on power, does it rev clean but fast and weak? Is it slow to rev? Does it hesitate when you try to feed it the berries?

 

[19brendan81]

Jetting is what RB did for me....cant remember exactly what it is...think its a 42 pilot and maybe 172 main? Does that sound right?

"On the topic of engine down on power, does it rev clean but fast and weak? Is it slow to rev? Does it hesitate when you try to feed it the berries? "

I would say it revs clean but is weak. Most of my testing I am doing on tarmac...and it certainly scoots along revving freely, but it doesnt pull your arms at all...its very very easy to ride. According to the electronic tacho I have on the bike it will rev out to 8.000 RPM when riding....maybe more even.

"take the time to run the bike with the RHS powervalve cover off and confirm the PV is working with the engine"

Will do.

 

[Jakobi]

I think the older models signed off a bit earlier than the newer ones. My 300 will do 9500-9800rpm. A lean bike will rev clean, it will sound extra raspy/tinny, run hot, and make weak power. The pilot and needle have very little effect here. They basically cover idle - 1/8th throttle and WOT respectively.

I'd be popping the slide out of the carb again, checking what needle is in it, and what clip position. You mention that you are in Australia. Whats your temp, RH and altitude? A 172 main does sound a bit on the lean for a straight taper needle CCK/CEK which is generally what RB uses. Most would use a 178-185 with that needle.

Does it ever boil over? A quick check would be to move the clip down a position or even 2 on the needle and test again. If you see an improvement in power you know you're onto something. If not it very may well be electrical. Its about trial and error and diagnosing what helps and what doesn't.

 

[19brendan81]

Bike defo has a CEK needle in it currently.

Yes - it has boiled over the last two times I rode it. First time was overcast, temps in low 20s (celicius) and I put it through 1 hour of gruelling single trail. Second time was mid 30s, after a super steep but short (5 min) run up an old abandoned firetrail. I have also noticed that the temp warning light on the aftermarket trail computer comes on very often when I do uphill runs.

If it was running lean though...why do I need to have the screw all the way in to make it idle?

Brendan

P.S all the rides I have been doing lately have been 600m to 1000m in altitude (Im in canberra and ride in the mountains nearby mostly). As ive been riding over summer its been mild summer temps. Humidity has prob been 50% or so...really not sure.

 

[Jakobi]

A few things here.

If you are lean on the needle you can have to go rich on the pilot to stop the hanging idle. Big pilot and Air screw (small brass one) almost closed.

If you are rich on the pilot you often have to lift the slide (idle screw wound in) to lean things out enough to get an idle. Lifting the slide lets more air in to correct the mixture

You can be rich on the pilot and then lean on the needle and rich again on the mains. It doesn't need to be uniform across the board. From what you say about loading the engine and hill climbs and engine temps I'm going to punt that you are lean on the needle. The needle has most effect at 1/4 throttle tapering through to 3/4 throttle and in conjunction with the main at WOT. Think about where you generally hold the throttle for a hill climb. Not wide open and definately over 1/4 throttle. Drop the clip one position and try again.

 

[lonetree]

my 04 has a 40, 180 (could probably go a 178) with a N1EG needle 2nd clip from top from memory...
I've never used a CEK needle but you sound rich on the pj and lean on the main.

 

[Jakobi]

40 N1EG#2 178 is very close to 42 CEK#4 185. The CEK is actually leaner than the N1EG from idle to 1/4 throttle extending to 3/8ths (which is where the N1Ex is always rich).

 

[socalscott]

You are not alone.
I don't think there has ever been advice that resolved the issue. One guy removed the silencer and ran it down the road WFO thinking it would grenade. It fixed it

I've been down this road. Mine had no power after half throttle though. The odd part was that a new top-end helped bit(including cylinder/case match), PV gov helped a good amount, new reeds helped a bit, RB carb wing and idle circuit helped a bit, a clogged pilot jet at some point too.
The power was odd at this point. Mostly like a 4 stroke in the tight trails, but hit nicely at times in an open section if long enough.
The final issue was play in a float pin tower hole. To Ron's credit he did mention this issue. Javier of TrailTricks said this was causing the float bowl to shift, resulting in a very rich condition. He installed a handy 36mm body and it runs normal, but not strong. The crazy thing is I had early on installed a 38mm winged carb off my 2hun and it didn't help at all.

So yeah, my '04 should rip hard, but meh. Oh, yeah, have a good laugh when you see how shrouded the ports are @ BDC. Correcting that along with decent squish didn't change a thing. Required a 3mm custom gasket! No bottom loss and no top end gain? No change.

I just keep it for extreme trails.

Good luck

 

[19brendan81]

Thanks for the input guys. I rode home after my last post and noticed the bike was idling really high, so backed the screw out and its great now. Sorry for the bum steer. Will try some jet changes as suggested and will confirm power valve is working then will write back.