85 r problems...have a look...

[DeePa]

I was riding int he rain yesterday when my 250r suddenly had no high rpms...it would like rev then bog and rev then bog very fast....

then i twould die out once in a while then was ok for the rest of the ride.

Would water cause this? I just pulled my plug and it was black for the first 4 threads or so and on the electrode...that means unburnt gas and its running rich right?

What effect does humid weather have on jetting?

I have an aftermarket pipe and k&N filter for mods. I am running either a 148 or 145 main jet and a 45 pilot jet. I have a 150 in my toolbox as well as a 143...The needle clip is on the second groove...I am going out there now to try to move it to the third groove and see what happens...lowering the clip raises the needle and leans out the mixture right?

Any pointers on what happened yesterday? It died out once or twice but I could start it right back up with a few kicks. I already bought some dielectric grease and greased up every electrical fitting I could find.

On another note...on my plug boot, the little collar that goes around the metal top of the plug comes out of the boot when i pull the plug out. it stays on teh top of the plug, and it still runs like this. Should I worry about it?

Another thing...when i pulled the plug, i hooked it up to the boot and kicked the maching over while holding the plug. Shouldnt i get zapped from this? I couldnt find any color spark while checking, but right when i installed the plug and kicked, it fired right up.

The bike seems to run great on low to mid rpm's but starts to struggle on the highs.

Thanks,
Mike

[BigGreenMachine]

Lowering the clip raises the needle out of the seat and richens your settings.

Heres a good read on jetting.

http://justkdx.dirtrider.net/carbtuning.html

Sounds like you either soaked the airfilter or water on the stator coils. That or your main jet is way too small for the mods you have.

[dirtybiker71]

Definitely replace that plug cap as well. The conductor shouldn't stay on the plug when you remove the cap. It could have been intermittently losing spark.

[Dirtcrasher]

Did you simply foul the plug?? My 85R fouled plugs quite a bit, turned out to be sloppy crank bearings and seals upsetting the fuel/air mix. Until I rebuilt it, it would run great for awhile and then problematic.

[DeePa]

i was running the 145 jet...i just put the 148 in and it seemed to be better, then the 150 would bog it out again.

Its like the 1/2 throttle and full throttle are the same exact rpms...except 1/2 throttle seems to run cleaner and smoother, while full throttle bogs a bit and doesnt sound as crisp...

definately didnt get the air filter wet, nor did i foul a plug because i just used a new one and it was the same problems.

i checked inside he stator cover and there was no water in there...

I just dont get it and its really starting to piss me off.

It seems like its either not getting enough gas to get past 1/2 throttle or too much when it gets past 1/2 throttle and since this is my first 2 stroke, i cant tell the difference.

do you think the 150 is too small for reeds, pipe, and filter? Whats a more feasiable main jet number?

thanks ofr all of your help...

mike

[Solid Snake]

Could be water in your carb bowl. My little brothers 125 ttr was doing something similar to that and even though his is a four stroke and yours isn't it will have the same effect. Try taking off the plug on the bottom of your carb bowl (if your particular bike has one) and drain the fuel. Then shoot some carb cleaner or something like that up in there, spray alot, don't hold back.

Quick question, was it doing this before you rode in the rain the other day?

[DeePa]

i dont think it has ever ran 100% since i have had it.

it was running ok until yesterday. I already drained the carb 2 times when i was changing jets today, so any water is out of there now.

thanks
mike

[ChrisD]

I would fix the obvious first...I would get a new spark plug boot. It's been a while since I pulled one apart. Does the one you have screw into the end of the coil wire? If so, then cut off about 1/4 inch of the coil wire and rescrew it on. If not, is the one that has a sharp end that sticks into the wire at a 90 degree angle? If so, do the same drill by cutting the end of the wire off and use a pair of channel locks to squeeze the end back into the wire. Then push the boot over it.

Do you run with your airbox lid off? If it's dry out today....not here....I would pull the lid off and see if that fixes your problem. If so, then you are rich, but I honestly doubt that would be the problem since it ran OK until yesterday. Is your airbox bone dry? I remember a freind had problems when it was wet. It turned out that his air box had a crack in the bottom of his box and water was getting in. Likewise, I would check all of your intake connections to make sure that one of the connections hasn't popped off.

[DeePa]

the boot isnt threaded...as far as i know. The coil wire has a hole in it and the boot just pushes on as far as i can tell...The main problem with the boot is that the piece of the boot that the spark plug connects to comes out of the boot when i remove it from the plug. The collar piece stays on the plug when it shouldnt.

Where can i find a replacement boot? Mfgsupply.com has some butim not sure which one to get...heres the link to them

http://www.mfgsupply.com/MowerSparkBoots.html i know it says mower but i have no idea where to buy them from.

i also found some at hyper parts...

http://www.crosstec.com/wc.dll?ctwp~getitemclass~1001~1002~1~minor~00001~0 0029~Any


I really have no idea whats going on. I think I may try to drop a 143 back in there and see what happens. Maybe im way too rich. I just dont get how half throttle sounds like full throttle then past that it just runs poorly. I also dont get how the plug wont zap me when i hold it and kick the motor over, but itll start right up with no problem whatsoever.

Hopfully we can figure this out...I wish I had a tach to see where its revving out at. Maybe theres an air leak so its revving a lot higher than it shoudl be sooner at teh throttle position. It idles perfectly fine though.

Thanks,
Mike

[jason85atc250r]

just swap the coil off your 350x it'll work you have to unthread the top of the plug since 350x's use just the threaded stud. it plugs in exactly the sameon the main harness. then if your problem goes away you know what it is.


i did it to my trx 250r till i just got a Jansen supercoil.

[DeePa]

it seemed to run much better, but also its nice and dry now.

The airbox lid didnt make a difference whatsoever.
Maybe a little bit...

Tomorrow im going to switch coils once or twice to see if it makes that big of a difference. But it running much better after i switched em up, and now i can see the spark when i kick it over...unlike before but it was also nice and dark this time.

Ill go try the other one real quick and see whats up

Mike

[DeePa]

i just tried them both again, and spark wise, they seem almost exactly the same. Both put out a nice blue spark when held near a cylinder head cap but and both shock me pretty well when kicked over pretty hard with my hand.

this is leading me to believe that it has to do with jetting.

Then humidity in the air caused it to run really rich, now that its dry, it could be better.

Any other suggestions?

note... the plug cap does screw on....

I definately need a new plug cap...the original one is all busted up where the plug sits.

Mike

[Mosh]

buy a 5 dollar plug boot.they are not supposed to "pull off the wire" they have a self tapping thread to the boot that should screw on to the wire tightly.the end of your coil wire is worn out.trim a 1/4 inch off the wire and replace the boot.it should fix your problem.if it is dry and runs good,spray some water with a salt mixture, on the coil wire and see if it acts up.if it does replace the boot.p.s.the salt acts a conductor to find weak connections.

[jason85atc250r]

maybe it just got some water down in by the fywheel and stator and it dry out from sitting. i havd it happen to mine.

[DeePa]

i just had a chance to use the 350x coil then the 250r coil, and the 250r coil gave me trouble again, while the 350x one ran flawless.

It still seems to hit the highest revs then not rev any higher, even though there is 1/4throttle left.

I think im still a little rich with airbox lid on (i want to keep it on) and needle on the 2nd clip again with a 150 main jet. I may try to drop it down to a 148 and see how it responds. The color around the plug's electrode is a deep coffee brown/blackish.

What boot is the correct one to buy? SHould i but a coil also or no?

Mike

[Mosh]

buy a ngk boot.the kind that uses the little top on the spark plug.instead of unscrewing the cap on the plug,tighten it with channel locks.these boots last a lot longer and fit the plug tighter.if you get the boot that just snaps over the threads of the plug,they tend to loose the tight fit after 6 months or so.as far as the coil,it might be bad,but i doubt it.get the boot on and go from there.one more tip,before every ride, hose down your coil wire and boot with wd-40. it pushes the water away if you get into it.been doin this for ten years and never had a problem after hitting water with my coil.use the wd-40 on all your electrics after washing the bike.it really helps.