View Full Version : Ahhhh my flat tracker is driving me nuts, 35mm PWK
Billy Golightly
10-20-2006, 03:18 PM
Well it runs but not very well, I dunno whats going on with it. I'm running a #55 pilot jet, DGK needle on the second from the bottom groove, and a 150 main. It keeps acting like its running out of gas in the low and mid. Not like a running lean revving real easy to the moon, but more like a 4 stroke does when it runs out. Hit and miss, and hit the throttle and it pauses before it revs. Plug reads dark, and it smokes like crazy. If I go leaner on the pilot or needle the smoke goes away some but it runs worse and will just miss and die sometimes. Its almost like the float is screwing up and not letting fuel in sometimes but it seems to be fine when I'm wide open so I doubt thats it. It just doesnt "feel" rich when its acting up, its weird. I had to switch from the original PJ because the entire choke assembly pulled out of it, and I had this carb on the other R. The jetting seems to be pretty close to what it was on the PJ. Main is a little bit leaner and pilot a little bit richer by about 1 size each and thats it. Any ideas ? :(
Dammit!
10-20-2006, 03:26 PM
Are your reeds in good shape?
reeds? fuel inlet clogged on the carb? choke stickin? I hate weird carb problems
Billy Golightly
10-20-2006, 03:31 PM
I'd guess the reeds are in good shape, it ran fine pretty much with the other carb before the choke incident. Inlet on the carb is good, get good fuel flow out of the tank petcock. float doesnt seem to be sticking. I gotta race tomorrow and if i dont get this thing fixed I'm gonna be severely pissed :(
yea me too!!! errrrrr I dont have naything here to help either
Dammit!
10-20-2006, 03:37 PM
You say you've tried a leaner pilot. What sizes did you try? 55 just seems big to me. I'm running a 52 in a 38mm pwk just for comparisons sake. I think I could probably go down to a 50.
Also, I know what you mean when you say it doesn't "feel" rich. I've gone the wrong direction with jetting before too because it doesn't feel right. Sometimes when you go one way and it doesn't improve you gotta go against your gut and try the other one.
X2guy
10-20-2006, 04:01 PM
I have a 42 pilot and a 178 main in my 40mm PWK. I'd say go leaner on the pilot. You will also probably need to go a little richer on the main as a result.
Billy Golightly
10-20-2006, 04:05 PM
I've been down to a 45 pilot and everything inbetween and the results are the same or worse the leaner you go. I dropped the needle clip all the way to the bottom groove now and it wont run at all. It did crank once but I had to hold it wide open and it wouldn't rev at all. Still running the 150 main...
X2guy
10-20-2006, 04:12 PM
Your clip is in the bottom groove? The groove closest to the point of the needle? This pulls the needle up out of the main jet. If this is so you have actually made it more rich.
Billy Golightly
10-20-2006, 04:15 PM
yes, its at the richest setting beacause the way it was running it felt lean, but now it wont run at all. So I guess my "feeling" aint to good.
86waterpumper
10-20-2006, 04:37 PM
I agree with what a few others have said billy, that is a huge pilot for that carb. My gas gas 300 has a 38mm pwk, and most of these run between a 42 and 45 pilot. The pwks also seem to be notorious for having a issue with the non replaceable needle seat wearing, like this thread talks about might be worth checking out
http://www.smackovermotorsports.com/bb/showthread.php?t=2611&highlight=pwk+needle+jet
you ought to find you a lectron haha I love the one on my R, but that's because soemone else who knew what they were doing jetted it lmao jetting on a two stroke is definately a art I haven't got down yet by any means.
The O-Ring in the choke assembly good?
Billy Golightly
10-20-2006, 04:55 PM
well I dropped the pilot back down to a 48, and put the needle at the leanest posistion and it still wont even fart. Replaced the plug, have fire. Bowl is filling with fuel...Maybe I'll go see if I can put the old carb back on, hell I dont know.
air leak? I'd spray some WD-40 around to see if there is an airleak somewhere.
Billy Golightly
10-20-2006, 05:41 PM
Well I cant get it to do *Edited**Edited**Edited**Edited* now. I've got spark, got fuel, got comrpession. I even tried a small shot of starting fluid and it wont pop off. Plug is semi-wet so fuel is getting into engine. I guess I'm out for tomorrow :(
wtf?!! no your not!!!! dammit!!!! make sure the motor didnt get wet sumped somehow, maybe the lower end has to much fuel in it to start, If Ive beend screwing around with mine I have managed to do that forgeting to hook up somehting else.
Billy Golightly
10-20-2006, 05:54 PM
I was thinking that but if it is, then its a problem with this carb and I cant do anything about it anyways, can I?
well didnt you have another carb? when I wet summped mine I acidently fouled the plug one time trying to start it turned off (yea duh) well I kept kickin it choking it gassin it and managed to wet sump my lower end, put a new plug in and it would spit and sputter then nothing, after scratching my head for a while, I pulled the pipe off and it was soaked! tipped the bike up and actually poured pre mix out! dosnt help that I have a 42 mikuni on it.. well put a new plug in after a few mins of dry out and zing! started right up!
BigGreenMachine
10-20-2006, 06:39 PM
Is the float height correct?
Billy Golightly
10-20-2006, 06:52 PM
Well I'm out. I pulled the intake out and blowed the crank case out with air and got a little fuel but not alot. I put it backtogether and sat the tank on it, cranked and idled the first kick. Bolted the tank back down and put the seat on it, wouldn't do *Edited**Edited**Edited**Edited*. Evidently it had already filled up the crankcase in that short amount of time (I had the petcock off too). In adition to that I found the piston has a pretty good sized crack in it on the intake side of the skirt in the middle of the cutaway. So I'm done until I can get all that fixed and get a different carb. I dont know whats wrong with that one but I'm to *Edited**Edited**Edited**Edited**Edited**Edited**E dited* pissed to mess with it anymore for a couple days.
Bryan Raffa
10-20-2006, 06:56 PM
dam billy when it rains it pours!!! sorry about you luck..
Yamahondaman
10-20-2006, 07:02 PM
DANG !!!! how come i can't live Closer to all of you Guy's !!!!
i can get a ATC Motor for you to Race With !!!
it's got the "special" Hole ABOVE the Exhaust with LEAD in the Crank !!! 102 MPH
Billy Golightly
10-20-2006, 07:06 PM
I guess I'll take it apart and try and get it fixed in time for that race next month in Valdosta GA. Hey Ron you think you might make it up for that one on the 18th of november?
Yamahondaman
10-20-2006, 07:08 PM
HUMMMM ???
COLD ??? up there then ??
it's warm down here !! :naughty:
is it a OVAL Thingy like in Jasper ??
Billy Golightly
10-20-2006, 07:13 PM
Yeah it is as far as I know, its not near as sticky surface wise either. Its a little bit looser from what I understand.
Yamahondaman
10-20-2006, 07:15 PM
if the Cash is right by then ...... maybe me and THAT THING i'm Married to can go
Bryan Raffa
10-20-2006, 07:27 PM
I love it... THAT THING....:lol: :lol: :lol:
Yamahondaman
10-20-2006, 07:37 PM
turn em ALL upside down and........................ they L@@K THE SAME !!!! :lol:
Hey Bryan ........ Washers shipped today !!!! :w00t:
I would definitely check the float height in the carb and also do a leakdown test on the motor, maybe even a blown crank seal?
ok well I'm going to wait it out till the valdosta race, I want to run with some more trikes, aslo jasper is about an hour and some away from me, so Im going to save a few bucks and race in valdosta (10 mins from me) and the track there is a little loser and it has banked curves!
Yamahondaman
10-20-2006, 08:20 PM
i think he needs a PWK 39mm..... 58 Pilot,CEG Needle"2nd.Clip", 180 Main !! :naughty:
ChrisD
10-20-2006, 08:35 PM
Carb problems suck, but I wouldn't discount the cracked piston. I had a problem with cast pistons. I cracked 2 Niks in a row and my bike wouldn't run for a danm. If your piston is cracked, I would start there, especially if it ran OK before.
Personally, I would go to a 39PWK. I wouldn't bash that carb, I have never had a problem with them. I can't stand my Mikuni. I didn't like the Lectron, and I didn't like the $25 jets you had to buy for it either.
I run a 39 PWK on my "stocker" with a 60 pilot and a 190 jet in the summer. It works great.
If you have a crack in your piston, like I said before, I would start there.
Good Luck
jason85atc250r
10-20-2006, 09:11 PM
if he has some serois port work dune to it the 35 carb will be way to small to get it to run rite no matter what you jetting you do..
Yamahondaman
10-20-2006, 09:16 PM
i agree !!! Flat Track Racing .................. BIG CARB . !!!!
BBBRRRAAAAPPPPPPPPPPPPPPPPPPPPPPP !!!!!
the 39 PWK or 38m A/S would definitely be a better choice in my opinion.
If Billy wants to upgrade I think he knows where he can get rid of that 35mm, lol.
Billy Golightly
10-21-2006, 09:25 AM
I dont think the carb size is the main issue, because before this I was running the stock 34mm PJ and it ran good...ChrisD I think you might be onto something though with the crack in the piston being part of the problem. It had to have just happened recently because I dont see it holding up to wide open continously like the last time I raced it. Who knows though. The bad thing is the previous owner of this R told me he was pretty sure the cylinder was on last bore, and it had all the nice porting on it :( I do have an LRD cylinder he gave me with them that needs bored though, maybe I can use it.
Yamahondaman
10-21-2006, 06:41 PM
on the 39's.....................or PWK's .......................
other than the Clip Breaking .... i have seen "THREE" PWK's in the last 6 Year's that the Rubber Seal "in the
( NEW ) Carb." was Bad .... what that does is Let Fuel in ALL of the Circuit's and you CAN NOT GET IT JETTED ....
ChrisD
10-21-2006, 10:13 PM
The thing that sucked with the cracked piston (the first time) was that the bike ran, but ran like crap. You would think that it was the carb, stator, or someting else, but the piston was the problem for sure. I didn't figure it out until I pulled the head off out of frustration.
I use the Wiseco because I run the bike WOT the whole time....really. It is pinned from the time I start the race until it's done. I don't know what you have in your bike now, but I have to laugh everytime someone tells me "...the cast piston is better because you can run closer tolerances..." crap. If you flat track your bike, it takes a toll on the motor because it is usually WOT.
Anyway, enough preaching. I would swap out the piston. Check the bore measurement. You may not need to resleeve it. The bore may be fine, but the piston gave out.
The 35 has got to go though. It's a 2 stroke....more air, more fuel, higher compression, more power...
Good luck!!!
Billy Golightly
10-21-2006, 10:19 PM
Thanks Chris...I think I'm gonna work on pulling the entire motor tomorrow and cleaning off the table here in my room where I can dissasemble it. I also need to change the main bearings because the were a little loose feeling.
Billy Golightly
10-22-2006, 09:06 PM
Well I started taking it apart this afternoon and I had it standing the grab bar degreasing the bottom of the engine before I removed it, and found one itty bitty little tiny pin hole in the bottom frame rail that looked like rust. I went and got a chipping hamer and tapped around on the bottom of rails and found enough soft spots to make 8 or 9 holes after tapping on them with the hammer. I also found another spot that caved in after a little bit of tapping but didn't bust all the way through like the other ones....So the bottom half of my frame has pretty much rusted from the inside out it appears :(
Somekindofjerk
10-22-2006, 09:10 PM
Man billy, this just isnt how a project is sapposed to go is it. Going to tig up a new peice or get a new frame?
Billy Golightly
10-22-2006, 09:23 PM
I dont know...I think for now I'm just gonna go with a new frame. This might be a good time to use this one to start on 250r frame jig I've been wanting to do for a couple years now though.
ChrisD
10-22-2006, 09:26 PM
make it from aluminum....make it light!!!! then put me on the list for one. I've been on a mission to lighten my bike and have always wanted to make an aluminum frame, but do not have the time, nor the skill to make one.
x.system
10-22-2006, 09:38 PM
make it from aluminum....make it light!!!! then put me on the list for one. I've been on a mission to lighten my bike and have always wanted to make an aluminum frame, but do not have the time, nor the skill to make one.
I tried to talk Hornetpowersports into making me an aluminum frame about 2 years ago, I still want one and have been thinking about getting it done.
Billy Golightly
10-22-2006, 10:16 PM
make it from aluminum....make it light!!!! then put me on the list for one. I've been on a mission to lighten my bike and have always wanted to make an aluminum frame, but do not have the time, nor the skill to make one.
Thats the idea :D Making the jig will be the hardest and most time consuming thing for sure...And I've honestly never did any type of work like that. But, it can't be to bad and as long as it fits everything on a stock frame and whatever you build fits the jig theres not much that can go wrong.
And heres the pictures of the bottom of the frame, whats left of it anyways. Like I said none of those holes were there but after tapping around with the chipping hammer they developed because they were very thin spots. All the little dots are from the end of the chipping hammer, me checking around to see if there were anymore. Those were all I found, but they were more then enough :(
Oh yeah I almost forgot, like my custom ultra-light handle bar levers? :Bounce
Billy Golightly
10-22-2006, 10:21 PM
And heres the last one of the rust on the bottom...
x.system
10-22-2006, 10:28 PM
I see you flipped your left rear around, ever get a chance to try it out?
Billy Golightly
10-22-2006, 10:34 PM
I tried it out a little bit around here out in the field but never got to make it to the track with it. It was kind of different feeling, but I think I can get use to it.
Fox250R
10-23-2006, 03:49 AM
Well it runs but not very well, I dunno whats going on with it. I'm running a #55 pilot jet, DGK needle on the second from the bottom groove, and a 150 main. It keeps acting like its running out of gas in the low and mid. Not like a running lean revving real easy to the moon, but more like a 4 stroke does when it runs out. Hit and miss, and hit the throttle and it pauses before it revs. Plug reads dark, and it smokes like crazy. If I go leaner on the pilot or needle the smoke goes away some but it runs worse and will just miss and die sometimes. Its almost like the float is screwing up and not letting fuel in sometimes but it seems to be fine when I'm wide open so I doubt thats it. It just doesnt "feel" rich when its acting up, its weird. I had to switch from the original PJ because the entire choke assembly pulled out of it, and I had this carb on the other R. The jetting seems to be pretty close to what it was on the PJ. Main is a little bit leaner and pilot a little bit richer by about 1 size each and thats it. Any ideas ? :(
GOD! Do i know what this problem is! I have a 38mm a/s. I had a DGK needle in it and it was doing the same thing your explaining.Put the stock needle that comes with the carb back in.. Fire her up and see what happens...
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