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trikeman
06-27-2003, 06:30 PM
ok heres the scenario

i have my 84' 250r bored 2mm, cobra pipe, and boysen reeds. i have a 340 main jet in it, some times when i ride it, it's extremely powerful, but other times a moped can beat it in a race, now it's getting real bad, i start it up it revs fast then i have to hold it full so it can stay running, but then it dies. the carb is CLEAN, good gas, clean air filter , and getting gas to the carb.

so can any of the 2-stroke experts give a little help
dirtbike77
06-27-2003, 09:13 PM
u need to check and see what color your spark plug tip is? u could be running to lean?


what type of plug are u runnin?
trikeman
06-28-2003, 10:39 AM
sometimes it's black and dry, other times it's oily but still good spark. i never messed with the clip or jets it just began running like this one day, even with a good plug.
TimSr
06-28-2003, 11:32 AM
Sounds like a fouled plug. When it happens, immediately change the plug, and see if the problem disappears. Having good spark does not mean the plug is good. Bad plugs usally spark too, but not the correct path. If it does, then we can address the issue of why its fouling plugs. If it continues to run poorly with a new plug, it may be electrical. If it used to run okay, and just started doing this, DO NOT monkey with jets sizes and needle settings. You have some other problem.
trikeman
06-28-2003, 01:37 PM
yep with a brand new plug BR8ES & BR9ES it still does the same thing.
FullBore
06-28-2003, 05:18 PM
check everything on the inlet side is tight, eg where the carb is fastened to the motor and all those joints, sounds as though it could be an air leak.

Nat
trikeman
06-28-2003, 06:10 PM
i checked if everything is air tight and it is, this thing is pissing me off because everything seems in tact i dont have a clue of what it could be!?
wanta250r
06-28-2003, 10:19 PM
Maybe you need a new top end ?
trikeman
06-29-2003, 05:27 PM
it has a new top end with like 12 hours on it, well anyways today i put a different carb. on it, and i started it up and it reved up good, but i only put some gas in the cylinder,not enough to keep it running, i have to get it together the rest of the way and see what happens.
2strokepwer
06-29-2003, 07:40 PM
this is just a thought, could it be that your crank seals are wron out and need replacing?
Truckster
06-30-2003, 10:18 AM
i checked if everything is air tight and it is, this thing is pissing me off because everything seems in tact i dont have a clue of what it could be!?


Start motor, and Spray (dont know if you have WD40 in USA?) or Aerostart around the carby and inlet parts to see if you have an air leak.

If the engine revs its tits off, you have a leak there.

Other thing, have you had the head off since rebuild to see the condition in there?
TimSr
06-30-2003, 01:10 PM
When its not working, does it have a miss or does it fire smoothly, just with no power? Does it rev all the way out at max RPMs, or does it just kind of start to bog out when you get half way up or so?
ATC crazy
06-30-2003, 03:55 PM
(dont know if you have WD40 in USA?)

It's man's best friend over here :-P
trikeman
06-30-2003, 06:00 PM
ok today i took off my dg silencer, and put the stock tube without any baffler, or packing and it was as powerful as i ever felt it,(it actually scared me :oops: ) but when i put my dg back on it took a while of holding it full throttle for powerband to kick in, but it started running good today, so i think we're startin to solve things.





rich
J.D.
06-30-2003, 07:04 PM
(dont know if you have WD40 in USA?)

It's man's best friend over here :-P


Bullcrap! WD-40 is crap, I use PB B'LASTER, it is THE best stuff.
350Xccelerator
06-30-2003, 07:40 PM
trikeman, your R has a cobra pipe? i didn't know cobra made 2 stroke pipes.
bakeban
07-01-2003, 12:45 AM
(dont know if you have WD40 in USA?)

It's man's best friend over here :-P


Bullcrap! WD-40 is crap, I use PB B'LASTER, it is THE best stuff.

i must agree with the peanut butter blaster. that stuff is the bomb diggity
Truckster
07-01-2003, 01:14 AM
ok today i took off my dg silencer, and put the stock tube without any baffler, or packing and it was as powerful as i ever felt it,(it actually scared me :oops: ) but when i put my dg back on it took a while of holding it full throttle for powerband to kick in, but it started running good today, so i think we're startin to solve things.
rich


Is the weather different today from other days... Yes it can make a difference to modified bikes sometimes.


Sell the DG muffler, and go back to stock if its happier the difference in power would be minimal....
trikeman
07-01-2003, 05:57 PM
honda atc 70, yea it has a cobra pipe, the pipe that comes from the cylinder. the weather is humid so mabey that could be doing it? also i dont have an air cleaner on the carb. would that make a difference? i would sell the dg but the stock has nothing to make it quiet at all, and i know i would get into some trouble with how loud it is.
Andrew
07-01-2003, 06:12 PM
i dont have an air cleaner on the carb. would that make a difference?. shock VERY BIG DIFFERENCE!
trikeman
07-01-2003, 07:27 PM
it would make it run bad?
TimSr
07-01-2003, 08:06 PM
Itll make it run very lean.
trikeman
07-02-2003, 03:50 PM
what would i have to do with the clip to compensate for the difference?
TimSr
07-02-2003, 05:47 PM
Youre a lot better off running an air filter than trying to carburate to compensate for running without one. The biggest wear factor on a 2 stroke is foreign matter coming in through the intake, mostly due to neglect in air filter service. Running without one will accelerate wear way beyond neglect. You stated it was bored 2mm, which is probably max. Its a matter of how long you want that bore to last when you will have to resleeve. Also, you stated the carb is clean. If you are running without a filter, that could change in a few seconds.

The needle cant deliver beyond what the main jet is capable of, so you cant richen your overall flow with the needle. It requires a main jet change. If you decide to continue running without an air filter, and rejet accordingly, keep us posted, and run frequent compression checks so I cant start a pool where we guess how long before your bore pukes.
trikeman
07-03-2003, 05:07 PM
ok i'll get a filter on it ASAP
atc86r
07-03-2003, 05:17 PM
wise move.
trikeman
07-05-2003, 10:07 AM
ok i have a filter on it, but it smokes like hell, and has very little power
md1985250r
07-05-2003, 11:52 AM
what mix are you running?
trikeman
07-06-2003, 02:03 PM
30:1
hondaATCman
07-08-2003, 02:23 AM
how long have you been running without an air filter?? dirt and engines don't like each other very well, it'll destroy your piston and cylinder (and other parts too but those are the main ones) You might wanna take a look in your top end and check everything out. Also, I don't know if this affects trikes or not but if you take an air filter off a lawn mower it won't run right because it doesn't have enough restriction to mix the air and gas right.
hondaATCman
07-08-2003, 02:29 AM
If it smokes and doesn't have power, I'd say your rings are worn out from all the debris getting into when you had the air filter off. Also, have you had it bored out before? Cause a 2mm bore makes that cylinder wall very thin. And when you have to resleeve, get it bored to standard and then go .010" oversize every time you get it bored from there. Never go from standard to max bore at one time. Bore in increments.
md1985250r
07-08-2003, 06:59 PM
30:1


WHAT KIND OF OIL??? 30:1 SEEMS KINDA RICH....MOST PEEPS HERE RUN 50:1 I THINK....WORKS FOR MY 250R...AMSOIL ;)
trikeman
07-08-2003, 07:26 PM
i've only ran the engine for probably like 2 hours total without a filter, on a road, not off road. it has good compression too.i've had the top end off and everything inside looks good, rings,bore etc... Yea it has been bored out before i just had it go from a 1.5mm to a 2mm bore. i should get the oil that you are talking about. right now i'm using artic cat racing oil.