350 pv no low end

[nosno]

Have esr 350 pv ported for low to mid running. Have esr 6 pipe, cr ignition, cr reedcage, and 36 tmx carb. Plug reads great and bike runs good just does not seem as strong as it should. Honestly it feels like my 05 450r stock quad would run right with it. I was wondering how do you take the powervalve out? It has 2 allen head bolts on the cylinder and then 2 more smaller allen bolts on the end of the powervalve. Just wondering if it is sticking? If anything this bike has topend power and no lowend which is exactly opposite of what this thing is setup to do. Just fed up with spending big bucks and getting a 35hp (estimate) machine. Any suggestions?

[beerock]

Originally posted by nosno
Have esr 350 pv ported for low to mid running. Have esr 6 pipe, cr ignition, cr reedcage, and 36 tmx carb. Plug reads great and bike runs good just does not seem as strong as it should. Honestly it feels like my 05 450r stock quad would run right with it. I was wondering how do you take the powervalve out? It has 2 allen head bolts on the cylinder and then 2 more smaller allen bolts on the end of the powervalve. Just wondering if it is sticking? If anything this bike has topend power and no lowend which is exactly opposite of what this thing is setup to do. Just fed up with spending big bucks and getting a 35hp (estimate) machine. Any suggestions?

ya the pv could be sticking.

why are you running a 36mm carb on a 350pv?
you should be running a 38mm or higher, i would run a 40.5 and that trx6 pipe is not a big bore pipe, you need a big bore pipe for that motor.

If you ahve all top end and not much bottom end, my question is did this all of a sudden happen? did you lsoe bottom end on this setup? if you did then i would def do a compression test. normally when top ends wear out they will scream but have no power down low.

[nosno]

Running the setup because esr said it would work. Of course they tell you that. Engine has been this way from the get go. I bought it new and esr assembled it. Blew the tranny out after they built it. Complained to them about no power when they redid tranny and they put a different dome in. Don't think it made a bit of difference. Engine probably has 15 hours. Do you know how to take powervalve apart? Better yet how about buying a very nice 250R HAHA?

[beerock]

bro relax, that 350pv is capable of more then 60 HP

what kind of port job did they set you up with? it sounds like you have a trx 11 port job. i rode a 310 with a trx 11 and it was like a light switch.

a trx6 pipe on a big broe is completely constricting the pwoer that motor can make to top it off the trx6 isnt a good pipe anyhow.

[Chef]

That 350pv should be great off the bottom, especially with that little carb. My 425 RIPS off the bottom, like a tractor.

[cdrookie]

if the PV was sticking it's gonna affect top end performance not low end. the cr ignition doesn't do anything to help low end either.

[beerock]

Originally posted by cdrookie
if the PV was sticking it's gonna affect top end performance not low end. the cr ignition doesn't do anything to help low end either.

no its the other way around. the power valve changes the exhaust port timing to give mroe bottom end, at top end the valve is not even in the picture.

[cdrookie]

it depends on how it's sticking.

[beerock]

Originally posted by cdrookie
it depends on how it's sticking.
true that

[zedicus00]

you guys were prolly more right with the first suggestion about the carb being to small and pipe not being right. also the trx-6 isnt great anywho.

something else to check though, bbroken reeds or maybe an air leak. also what kind of compression does it hav.? low compression will make it feel topendish with no power down low.

im gunna b running a 40pwk on a 310 with a trx -5, yurs is capable of a lot of power if setup right.

[deathman53]

I was using a 38 a/s on my 310pv and I didn't think that was big enough, it didn't make that much top end for the setup, I went to a 39 pwk, I'm also using a cr ignition, cr reeds, and now I have a paul turner hi-rev pipe. I would go with a 40mm carb at the least, get a big bore pipe, and what kind of compression do you have???? I know my 310 I almost can stand on the kicker. you interested in selling your 36mm carb, I am in need of one for my woods racing atc250r.

[nosno]

Let me start with the simplest thing first guys. Please tell me the best way to find out if the pv is sticking or not. Then someone can tell me a good pipe carb reed setup so I can waste another $1000. I guess I am getting old and just don't like to tinker too much anymore. I think my ct310 ran better than this thing.

[beerock]

Originally posted by nosno
Let me start with the simplest thing first guys. Please tell me the best way to find out if the pv is sticking or not. Then someone can tell me a good pipe carb reed setup so I can waste another $1000. I guess I am getting old and just don't like to tinker too much anymore. I think my ct310 ran better than this thing.

it moves form the force of the exhaust gas, higher rpms allow the PV to open up and change the port timing. if its sticking you will notice it wwhen you try to move it up and down.

[Hoppedrap]

Originally posted by nosno
Let me start with the simplest thing first guys. Please tell me the best way to find out if the pv is sticking or not. Then someone can tell me a good pipe carb reed setup so I can waste another $1000. I guess I am getting old and just don't like to tinker too much anymore. I think my ct310 ran better than this thing.

What style powervalve? If its the newer style, take your pipe and flange off and stick your finger in there and see if you can manipulate the slide. 39 PWK, LRD's big bore pipe has gobs of bottom to mid, just doesn't rev out well

[wilkin250r]

My first thought is compression.

Who assembled this motor? Perhaps it has a spacer that is too large?

Is it a stroker?

What size dome?

I would suggest a simple compression test before you start jumping into the powervalve.

[nosno]

Compression is fine. This motor has had these running characteristics since it was new. ESR assembled it. No stroker, running 87-89 crank length. No spacer plate it is built into the cylinder or so I was told. The style of powervalve I have is just a oval shape. Has 2 bolts that bolt the whole assembly to the cylinder then 2 smaller allen bolts that hold what looks to be the cap with the breather hose fitting on the cap. Hoping I could just take the 2 top bolts off and take a look. I suppose the 2 bolts that hold it on the front of the cylinder will leak antifreeze like 1 of the exhaust bolts and 1 of the intake bolts. Thanks for the help guys.

[beerock]

I think your motor set up is GREAT for a 250cc size cylinder, for a 350p/v you could be backing up exhaust gas into the trx6 pipe. just a thought, doubt it but who knows.

if you say your compression is fine, and its been running liek this from the start. it could be a couple things.

1. thats the way the port job is.

2. broken reeds

3. dirty carb

4. timing off (broken woodruff key)

5. low compression (check the damn compression would you already)

6. this is my opinion and I doubt its the problem but it could be, to small of a carb and the wrong pipe.

[Hoppedrap]

Never heard of a built in spacer plate from ESR.

[zedicus00]

i must say i do agree wit da bee. (becuz its basically the same thing i posted earlyer)

no offence and im sure imma catch some slack for this but wouldnt call ESR the best R builder around, and even pro builders can make mistakes.

pull it all apart, check EVERYTHING, build it back up right yurself, and b bloody done with it.

[beerock]

Originally posted by zedicus00
i must say i do agree wit da bee. (becuz its basically the same thing i posted earlyer)

no offence and im sure imma catch some slack for this but wouldnt call ESR the best R builder around, and even pro builders can make mistakes.

pull it all apart, check EVERYTHING, build it back up right yurself, and b bloody done with it.

i once had a motor that i seized very slightly, the motor still ran but the piston was scored and would only run good when WOT

[zedicus00]

yeah i had one that they sent me one sixe under what i needed for rings. they were close enuf i couldnt tell they werent right by looking. after break in the thing only ran good at wide open throttle. it finally munched the top ring spat most of it out the exhaust and i rode it the like 5 miles back to camp with so lil compresion i had to run next to the thing get going and jump on it. i figured there was no one in heck it was gunna start again but the dang thing fired first kick still even like that. not enuf power to pull itself but it fired every time. if you started it on a hill and could get it wound up it seriously still didnt run all that bad, i guess spining at 9000 you dont need to hold compression very long anyways.

thas the craziest thing i ever saw, man you could turn the kicker with yur finger an the engine would roll over a couple times it was so low on compression.

[addictedtomud]

NOSNO, I too am less than impressed with some of the big bore motors I have had. I think you can change pipes and carbs until you're fingers bleed, but you still wont have what you're looking for. Hopefully it's just low on compression, then you can solve the problem.

1) I had an ESR 330 PV (bolt-on) with TRX7 port and it had similar power characteristics as yours: all mid-top end power.

2) Also had a PC2000 265 PV on a different machine and had the same result. It had midrange port by Paul Turner. I tried different pipes: FMF Fatty, ESR TRX6, & stock. Tried 38mm airstryker vs 36mm PJ without much luck.

3) CT410 (non-PV) motor was the only engine I ever had that did everything I wanted it to. It had not quite as good low end as my quadzilla but it would rip alot harder through the midrange and top end. CRAZY fast! I bought it used but sold it when I found out they were not reliable for trail/woods and made for drag racing only. And it was running on CT standard midrange pipe, nothing special.

I have resorted to stock cylinder until I can figure out the answer. WHO out there has a big-bore with monster lowend torque?? Preferably something 310-350cc

Good luck
Kyle

[Chef]

I like the PSI head for the very reason of compression...if you want some kick-***** low end, crank the dome down and let it rip your arms out. If you are on a big wide open track and need all the top you can get, back it off and see how it'll rev.

[zedicus00]

if you guys want grunt get a 330 and hav it ported for lowend, get an all around or lowend pipe, and get some SOFT reeds, and a 38 A/S carb. as the revs go up you get more power to a point anyways so if you want it to grunt dont go midrange setup, go all lowend... dont even think about trying to run v-force reeds on a lowend setup iether.

and power valves are over rated.

my .02

[beerock]

Originally posted by addictedtomud
NOSNO, I too am less than impressed with some of the big bore motors I have had. I think you can change pipes and carbs until you're fingers bleed, but you still wont have what you're looking for. Hopefully it's just low on compression, then you can solve the problem.

1) I had an ESR 330 PV (bolt-on) with TRX7 port and it had similar power characteristics as yours: all mid-top end power.

2) Also had a PC2000 265 PV on a different machine and had the same result. It had midrange port by Paul Turner. I tried different pipes: FMF Fatty, ESR TRX6, & stock. Tried 38mm airstryker vs 36mm PJ without much luck.

3) CT410 (non-PV) motor was the only engine I ever had that did everything I wanted it to. It had not quite as good low end as my quadzilla but it would rip alot harder through the midrange and top end. CRAZY fast! I bought it used but sold it when I found out they were not reliable for trail/woods and made for drag racing only. And it was running on CT standard midrange pipe, nothing special.

I have resorted to stock cylinder until I can figure out the answer. WHO out there has a big-bore with monster lowend torque?? Preferably something 310-350cc

Good luck
Kyle

Did you guys see an a post before i said i rode a esr with a trx11 port job? the motor was like a lightswitch it was boggy from 1/4 to 1/2 and would take off from 3/4 to WOT. ive ridden 3 esr motors, a 310 drag port, 310 bottom port,330 bottom port, 370 drag port. all the motors were light switch's. nothing like my 330

One thing that will make a huge difference in power all around is a BIG BORE pipe.If the motor does have a lightswitch style port job then the only thing you can do is get the most out of the bottom end with the RIGHT pipe. You can also run higher compression to get some low end grunt into it but then you have to run race gas. If you dont mind running race gas then go for it. I run vp c12 in all my motors now, even if its low compression, the lead additives help the motors longevity and runs cooler. Remeber though if you bump up the compression you will lower the rpm's.

my personal opinion on the esr trx pipes is there fit and finish is great, there BETTER then there port jobs. but the power obtainable with a CSR pipe is definately higher. If you want a big bore pipe for it thats the kind to get. Start saving though, theres a year wait on the big bore pipes form them.I DEF don't think the esr trx11 pipe is the answer either. you need a curtis sparks MX or TT BIG BORE. OR you can get a copy cat DYNOPORT which is an exact replica of the TT or MX CSR big bore pipe.


you probably dont want to be spending money on it right now, so first find out if the motor has compression with a compression gauge, not with your foot:scary:

if compression is good check the power valve, but if you said it acted like this form the begining why havent you asked ESR?

[wilkin250r]

Originally posted by addictedtomud
WHO out there has a big-bore with monster lowend torque?? Preferably something 310-350cc


Me.

Oh, man, my 340PV has tons of low-end, and absolutely no top-end at all, even with a mid-top pipe. Of course, the lack of top-end could have been the vibration problem.

In fact, it was so bad, in order to get any speed out of it, I had to gear it really tall. It was geared so tall, I had to shift at max revs just to prevent it from dropping out of the powerband.

I gotta revisit that motor and get it going again...

[nosno]

Could somebody please tell me if I can take the 2 top bolts off the powervalve to check the thing out to see if it is stuck? Don't want parts flying out at me unexpectedly or remove the top of it to find out that procedure tells me nothing. Have asked esr about the power problem and I just as well talk to the wall. If I ever remember to bring the compression gauge home I will tell you what it says. Already running c12 in it. Thanks for the suggestions again.

[beerock]

Originally posted by nosno
Could somebody please tell me if I can take the 2 top bolts off the powervalve to check the thing out to see if it is stuck? Don't want parts flying out at me unexpectedly or remove the top of it to find out that procedure tells me nothing. Have asked esr about the power problem and I just as well talk to the wall. If I ever remember to bring the compression gauge home I will tell you what it says. Already running c12 in it. Thanks for the suggestions again.

well take the bottom bolts off the PV and check to see if it is in proper working order. I have a feeling you got the lightswitch type port job.

if your PV is fine and the case is the port job. you rnext step is to deal with it and tune it with pipes and a bigger carb. like i said before if you want to broaden the entire power band on the bike dont go out and buy a trx5 or a regular 250-310 pipe. To do this right the first time you gotta go big bore pipe. I garantee the big bore pipe wil do insane wonders to the power. If i were you I wouldnt even bother with a kehin pwk 38a/s or a 39mm. just get the 40.5mm.

if your motor is a lightswitch style port job then going for a top end pipe will enhance the power characteristics all around not just top end.

[addictedtomud]

NOSNO
Yeah the PV is spring loaded, so just hold onto it when you remove the screws. It should be one big spring, nothing you would lose on the garage floor. Should not be any small parts that would "explode" upon dis-assembly.
Kyle

[addictedtomud]

Originally posted by wilkin250r
Me.

Oh, man, my 340PV has tons of low-end, and absolutely no top-end at all, even with a mid-top pipe. Of course, the lack of top-end could have been the vibration problem.

In fact, it was so bad, in order to get any speed out of it, I had to gear it really tall. It was geared so tall, I had to shift at max revs just to prevent it from dropping out of the powerband.

I gotta revisit that motor and get it going again...

Thanks wilkin250r,
Is this a PC2000 with midrange port job? What kind of pipe+carb? Do you ride in sand or woods?

Thanks
Kyle

[Chef]

Originally posted by addictedtomud
WHO out there has a big-bore with monster lowend torque?? Preferably something 310-350cc

Good luck
Kyle

I do.

PSI 425 PV.

[nosno]

Finally had a chance to do compression check and it is 210 cold using craftsman gauge. Powervalve was not stuck in cylinder but when you had the assembly in my hand it would stick in the upper position-not real hard but it would stay hung up. Rode it after the reinstall of the valve and could not really tell much difference. By the way what plug and gap should I be using with the cr ignition?

[beerock]

Originally posted by nosno
Finally had a chance to do compression check and it is 210 cold using craftsman gauge. Powervalve was not stuck in cylinder but when you had the assembly in my hand it would stick in the upper position-not real hard but it would stay hung up. Rode it after the reinstall of the valve and could not really tell much difference. By the way what plug and gap should I be using with the cr ignition?

did you clean the pv entirely?

if you did and its still doing it, its your port job... liek i said, work on getting a big bore pipe to enhance power all around

[zedicus00]

chef man that is simply beautifu, jaw dropping and stunning...

can i hav it?