my earlier post explained my popping, lack of rpms...etc. kind of what my wolverine does with the parking brake engaged. i have disconnected the wires going to the parking brake, which is supposed to tell the cdi to retard the timing, or whatever. no luck. still same condition. for some reason i have an active ground on both the black and green/yellow wire coming to the switch. i thought i would only have ground on one, unless the parking brake was engaged. i am starting to believe my cdi is bad. any thoughts or suggestions?

i have cleaned my carb, twice, and have made several adjustments that dont make the engine run any different. so, i feel as though i need to look elswhere for my problem.

does the rev limiter kick in if its in reverse?

 

check and see if any of the wires you disconnected plug into each other

 

i should have mentioned that i did try that already, sorry. anyone have a wiring diagram for an 01 beartracker? or know the pin out on the cdi? i would have to assume the cdi is getting a ground signal that is triggering the rev limiter.

 

After hours of going thru everything on this bear tracker, I have located this extremely common issue! Long story short, the air box inlet is to small for this atv. To fix the issue, either remove the airbox lid, or the best way, get some of the 1” air-box filters from Amazon or ebay, drill the holes and insert them into the airbox. This will give sufficient airflow for the engine. This ATV had a design flaw and it chokes itself out. Hope this helps everyone 🙏

 

If the air box is too small for from the factory then why dont they have this problem when new?

I have a 99 big bear that is acting the same way with multiple carb cleans, valves checked ok, compression good, checked brake switch, with or without air box, tested stator and pick up coil resistance and it still wont rev. Starts and idles perfect but when i try to rev it it just spits fuel back through the carb and dies until it recovers and idles good again. Why would it all of a sudden start working bad with no change in carb settings?

 

Change the plug, if you haven't already. Don't know why the OP should care that it won't rev in park, why would you want to? If it won't rev when in gear, then you have a problem, and it is possible for an ignition component to be the culprit. All you can do then is test the wires to the CDI and test the coil (though substitution by a cheap Chinese coil is easier). If it isn't those, it is probably the CDI, though I would be loth to substitute that, unless a cheap Chinese one is available.

 

Most times if an engine spits and sputters and won't rev in "park" as you say it probably won't rev in gear either. I replaced the plug and checked ignition components and it blows back through the carb and won't rev unless I go real slow on the throttle. Has barely enough power to pull itself. I wish I knew if there was a limiter other than the brake switch.

 

Give it a little choke, if it then revs without stuttering, it is running weak, if it is the same or worse, it is probably ignition.

 

Don't suppose you figure this out? Mines doing the same. I've replaced the entire ignition system. Rebuilt the carb probably 6 times now.. tried a new carb. Compressions good.. I'm out of ideas..

 

I have a Jianshe 250 which is a knockoff of the Bear Tracker. I put an eBay carb on it and had the same issue. It started and idled very well. When you gave it gas sometimes it would rev for a bit but most of the time it would bog out, backfire (flame shot out the carb intake), and spit fuel backwards into the tube coming from the filter box. From what I read/watched online this could be a sign of a lean condition. I opened up the top of the carb and took out the needle which has five adjustment slots. It was sitting in the middle so I set the c-clip to the lowest clip slot (to get more fuel) and put if back together. After that it ran SOLID, zero issues from idle to max throttle, no load and under load up to fifth gear.
So the main culprit was too much air. If it ran fine with no change in the carb I would say you may have an air leak at your intake boot, from the carb to the engine. Start the quad and spray some starter fluid all around the boot and see if RPMs change in the engine. If so you got yourself a sneaky leak and are most likely getting too much air.