I am a recently retired Power Equipment Instructor whom has been humbled by a 1999 sportsman 500 Please help!!! The subject is a 1999 Sportsman 500 serial#4XACH50A0YA180113
The vitals: 85# compression with compression release on 160#compression release off, Cylinder leakdown test less than 8% leakage
Ignition fires a 6mm gap 10-12 Kv on Peak Voltage Ignition Meter
Fuel( New carburetor and fuel pump and remote known good fuel supply
Symptoms:
Bogs and backfires after 1/4 throttle opening as if the reverse rev limiter is engaged.
Steps I have taken to remedy the problem: Replace the worn cam and rockers, adjusted valves and double checked valve lash .006 also checked cam timing twice. also checked compression release centrifical actuator and spring location and operation

Replaced with new stator,pick-up coils, CDI ,Ignition coil wire and cap and spark plug. and just recently a new ignition switch
Disabled the ETC Throttle control and reverse rev limiter( per one of the old posts from the OLD POLARIS TECH)
Rebuilt and then replaced carburetor and installed a new fuel pump
Checked air cleaner and air box
When I place a timing light the light breaks up when the backfiring and missing occurs This may point to the flywheel magnets however, this is an encapsulated ff97 flywheel that shouldn't Have the loose magnet trouble as did earlier models.

Please help the Grandaddy with the Grandaddy of problems. Mecster

 

Timing light test on spark break down is usually dependable. If it's flashing in time with the miss that could point back to the stator you installed. Some stators like some of the Chinese aftermarket carbs can be hit or miss. Only thing that I see that you haven't shown is to pull the black kill wire from the cdi to isolate it from the switches.Plus on a couple aftermarket stators people posted the pick up coil was too far from the flywheel. Check that the pick up coil face has no more than 0.35 clearance from the flywheel strip. I'd still make sure the carb has the right size jets and all opening are clear. Plus just to make sure the air box and filter have to be installed to test or for it to run right.

 

Thank you for your quick response! I did indeed replace the stator and pick-up with a chinese knockoff a Caltric to be exact. however, I did check the air-gap. Also the black wire going to the CdI unit unplug test has has been performed. I did check the resistance on the Caltric stator and pick-up and they are well within the OEM specs. The carburetors have been checked and doubled checked new and old one.
What do you think about going with the AC to DC system upgrade from RMstator RM40000
Also I have performed all checks with the airbox on. Also I have replaced the exhaust with a known good one.
Thank you

 

Just my two cents on the RM stator kits and the one you listed. If it's like the one they offered for the 700 that uses the lighting coil for an ignition source I'd still be leery. I've had these old Ducati lighting coils fail also then you're back to square one. Plus in your case you'd be tapping into an already suspect 30 buck Chinese stator. https://www.rmstator.com/en_ww/produ...5-2004-rm40000
IF you're sure you've eliminate any other problem such as the carb,ignition switch,left control switch,etc,I'd try a better quality stator to begin with. Higher priced,yes,but usually better results.Ricks or Ricky stators have good reviews plus I've used Ricky stators in the past with no problems. Ricky Stator - Products https://ricksmotorsportelectrics.com...-Stator-21_551

 

Hello OPT,
Thanks for your reply that makes alot of sense. I will be taking your advice and order a stator and pickup from Rick's thanks for the link. Also have you used any of the ac to dc conversion kits and if so how did they work.
I will let you know how things work out.
Thanks Again
Mecster

 

RM kits came out as a cheap alternative to the complete Kokusan kits for the 700. Some say they're ok,have had good results,but like I mentioned I've had lighting coils go out on those 700s and then you'd be back to where you started. The Kokusan replaced all electronics including the flywheel stator,cdi,coil and regulator. They may be ok for some applications,but I never liked shortcuts especially on electrical parts. Rm kits for the 700 were a cdi,coil and wiring harness.
The Kokusan offered much more but you paid for it also. Around $550 or so versus the $200+ on the RM kits in most cases.

 

Hello again OPT,
Would you happen to have the part# for the kokusa complete ignition system upgrade for the 1999 sportsman 500 also in the pic it looks like the magnets in the flywheel aren't encapsulated ??

 

These kits were only for the 2002 to early 2004 600/700 twins to change ignitions to dc. Your's is still magneto triggered,that is it's not dependent on the battery for ignition which again "imo" can be an advantage if the battery was to ever die,cable problem, etc. At least you could recoil start it to make it home. Later models did go to dc but no other kits from Polaris on the earlier ones. I'd stick with the stator you ordered or if you want to give the RM kit a try,it's about the same price. Yes on the 700 the flywheel magnets were exposed.They must have been using a better epoxy as I never had one fly off on one of these. Had a few on the other models over the years and that wasn't too good for the stators either when they did.

 

UPDATE!!! I just installed the RM 4000 AC to DC ignition kit from RM Stators and the Sportsman 500 runs great. THANKS for your wisdom from one old tech to another.
mecster

 

Good luck with that RM kit. Did you use the Chinese Caltric stator you bought or the old oem stator on your 500? Just curious.