800 just 6500 rpm.

[153nitrous]

i have a -03 800 in my -07 iq race sled and it doesn't rev more than 6500, it runs perfect all the way up to 6500 an just stops there. i have already checked the exhaust valves, TPS, CDI, and changed the stator. it does not have a detonation sensor and i dont think it suppose to either, its the older CDI (without detonation sensor). what happens if i put a cdi from an -02 on a engine that suppose to have the detonation sensor? please help me! the snow is coming soon

 

[Kraven]

i have a -03 800 in my -07 iq race sled and it doesn't rev more than 6500, it runs perfect all the way up to 6500 an just stops there. i have already checked the exhaust valves, TPS, CDI, and changed the stator. it does not have a detonation sensor and i dont think it suppose to either, its the older CDI (without detonation sensor). what happens if i put a cdi from an -02 on a engine that suppose to have the detonation sensor? please help me! the snow is coming soon

Both the short track 2002 and 2003 800's do not have D.E.T. sensors, I had a 2002 EDGE-X 800 and my bud still has a 2003 XC 800 that I still get stuck wrenching on.

The det sensor came out in short track 2004 for the 800 as far as I know. Not sure abour RMK's, you didn't mention where the engine was out of.

Can you install a timing light onto it and verify correct timing??

Does it free rev beyond 6500 r.p.m.?? Possible clutching/drivetrain/track issue or is it DEFINITELY an engine problem??

You didn't mention checking the fuel system, filter, pump?????

Hope this helps??

 

[theultrarider]

Sure sounds line an exhaust valve issue since it is right at 6500rpm which is where they open. Try zip tying them open and see what happens. Worth a try. What pipe are you running on that and who made the mods to fit it? It sould be a pipe issue. Did the motor run correctly when it was in the donor sled? The 03 800 vertical escape rmk was the only 03 motor that had a det sensor built into it. 04 it was in the prox2's and the escapes. 02 had no det's in anything, but the 02 800's ran way different timing than the 03 and newer 800's. Verify your timing as well. It could be clutching, but I can't imagine it being far enough off to only get 6500 out of it. Let us know what you find. I doubt it is a det issue either. If/when the det goes off, or activates, it stutters and misses really bad and limits you to more like about 4000rpm.

 

[knee deep in it]

check your temp sensor and wiring. i had a short in my harness (04 600) and it would do the exact same thing. The sled thought it was overheating and limited the revs.

 

[theultrarider]

check your temp sensor and wiring. i had a short in my harness (04 600) and it would do the exact same thing. The sled thought it was overheating and limited the revs.

Once again, it would stutter or miss and not get anywhere near 6500 if this was the case. You genreally can't get much over 4000 with a bad temp sensor. Worth a shot though.

 

[sled_guy]

You can't plug a non-DET CDI into a DET CDI harness or vice vrs.

You can, however, have the timing way off if you use an 18 degree flywheel with a 14 degree CDI.

Check the carbs and make sure they are opening all the way.

You can check the exhaust valves by simply removing the springs. It will make the motor doggy on the bottomend because they will open instantly, but it will pull on through to full RPM.

sled_guy

 

[knee deep in it]

Once again, it would stutter or miss and not get anywhere near 6500 if this was the case. You genreally can't get much over 4000 with a bad temp sensor. Worth a shot though.

mine ran perfect to 6500 rpm.

 

[153nitrous]

The guy i bought the sled from said the engine is from an 03 PROXr(but i am not 100%) my polaris dealer told me the 03 vertical escape and the
03 PROXr got the DET sensor.

it was a while ago i messed whit it so i forgot that i have checked the carbs, tried another fuel pump, tried a 18 degree CDI, tried another ignition coil, checked the temp sensor and it let through the right ohms,
i checked all the wiring,
i know You can't plug a non-DET CDI into a DET CDI harness or vice vrs, but you can change the harness from the stator and put a non DET on a DET engine.
(there is a hole in the head where a DET sensor i suppose to be)
i do not know if the engine ever ran okay, i bought the sled this way, taught it would be an easy fix
it does not free rev beyond 6500. so i do not think it is a clutching matter and it still got the 440 gearing.
i have tried a timing light and it looks like it misses a little bit, but only on one cylinder.
and some times it runs perfect trough the whole register (but only for 10 minutes or so)
it is slp twin pipes on it, i do not know who fitted them, i taught about that to and i think i will try a single and see what happens.

it is not like it doesn't have the power to rev more than 6500 its sounds more like an ignition problem (it misses and sounds real bad)

 

[153nitrous]

but it is strange if it is an ignition problem because i have tried whit another cdi, stator and ignition coil. the only thing i haven't tried is a different flywheel.

 

[augerin]

It sounds like you have probably already checked this but I have seen a loose flywheel cause a similar problem.

 

[153nitrous]

It sounds like you have probably already checked this but I have seen a loose flywheel cause a similar problem.

yes that flywheel have been in and out of that engine several times, so i do not think its that. but maybe something is wrong whit my flywheel?

 

[theultrarider]

If it is missing badly when you hit 6500 then it IS most likely either a temp sensor or det sensor that you are dealing with. You can run a cdi box from a non det sled on there. I have done that on my sled (03 escape) with my wifes 03 rmk. The boxes and plug ins are identical other than the det circut. That would eliminate the det. If it still does it, then it is you temp sensor wiring. The senors are terrible and are a known problem. I have also seen others that have a wire cracked or rubbed between the senor and the cdi box. The ohm's have to be just right or you will have the problem that you are fighting. You say, the head has the hole in it under the themostat for the det sensor, but there is not one in it??? In that case you HAVE to run a cdi box that has the det removed from from it, or didn't have one in it in the 1st place.

 

[153nitrous]

If it is missing badly when you hit 6500 then it IS most likely either a temp sensor or det sensor that you are dealing with. You can run a cdi box from a non det sled on there. I have done that on my sled (03 escape) with my wifes 03 rmk. The boxes and plug ins are identical other than the det circut. That would eliminate the det. If it still does it, then it is you temp sensor wiring. The senors are terrible and are a known problem. I have also seen others that have a wire cracked or rubbed between the senor and the cdi box. The ohm's have to be just right or you will have the problem that you are fighting. You say, the head has the hole in it under the themostat for the det sensor, but there is not one in it??? In that case you HAVE to run a cdi box that has the det removed from from it, or didn't have one in it in the 1st place.

i will try whit a new temp sensor. i have checked all wiring to the cdi, no damaged wires. yes the head got the hole for the DET sensor but no sensor in it. the CDI is a non DET...

 

[theultrarider]

The temp sensors can "look" fine but often break up on the inside. If the ohms are not just right you get what you are describing. Slp makes a Temp sensor "bypass" that the sell for "testing purposes". Alot of guys carry them to get sleds out of the mtns when a sensor goes bad, and I know some guys that just flat leave it wired that way to avoid the sensor problem all together. I would not suggest doing that, but try either the bypass or using a known good sensor. You don't even have to install it, just hook it up and see what happens. Also, sometimes the temp light will come on when they act up, and sometimes they won't. Also check to make sure your ground wires are hooked up. That can give you fits as well.

 

[153nitrous]

The temp sensors can "look" fine but often break up on the inside. If the ohms are not just right you get what you are describing. Slp makes a Temp sensor "bypass" that the sell for "testing purposes". Alot of guys carry them to get sleds out of the mtns when a sensor goes bad, and I know some guys that just flat leave it wired that way to avoid the sensor problem all together. I would not suggest doing that, but try either the bypass or using a known good sensor. You don't even have to install it, just hook it up and see what happens. Also, sometimes the temp light will come on when they act up, and sometimes they won't. Also check to make sure your ground wires are hooked up. That can give you fits as well.

my temp light have come on a few times. i really hope thats what caused this. thanks.

 

[Kraven]

my temp light have come on a few times. i really hope thats what caused this. thanks.

Real E.Z. to check the temp sensor, remove it, hook it up to an ohm meter:

68* F (room temp) 2432 OHMS +/- 250

212* F (place in a pot of boiling water) 192 ohms +/-30

Hope this helps

 

[FTXMOTORSPORTS]

Crank index is another one that most forget to mention or check-if she's twisted out of phase you'll pull your hair out trying to find the problem elsewhere. All you need is a degree wheel,dial indicator and 5 minutes of your time.

 

[Scott]

Let's try thinking outside this box....

Have you checked the primary spring?
When they break or totally sack out they act like this.

 

[FTXMOTORSPORTS]

Let's try thinking outside this box....

Have you checked the primary spring?
When they break or totally sack out they act like this.

Damn you Scott! thats the other one thats always overlooked....and I forgot about it....hanging my head in shame....

 

[sledhead Ed]

I had an 02 blade with a 910 bigbore in the shop that acted alot of the same way. It wouldn't rev all the time burble like really bad rich jetting and once in great while it would rev up and got proggresively worse. Had it on the dyno for short burst it would do it once in awhile take out on the lake it was terrible. Wouldn't tach up. after swapping parts with known good parts. It ended up being the mini harness that goes to the cdi. That had ohmed out good and passed continuity test. The only way to find it was swapping out with known good parts because I had already taken it to the dyno to make sure it wasn't twin pipes that where made custom or jetting or cdi or coil or ign switch or timing or temp sensor or detonation. So I knew it was electrical and I didn't bring a spare stator with me. That was basicly what was left besides the whole harness and I didn't find any pinch wiring or shorts. So I put a stator in no difference. I had already did an ohm and continuity on the mini harness becauase they are know to break wires inside the insulation and it check out good but that was all that was really left. So I took the harness off my 02 rmk and put it in and it was like you flip a light switch night and day difference. I had a prox with a big bore that we where trying five different pipe combos on the dyno one time that kept sputtering from 6000rpm and up, it had a bad voltage regulator. Just something I've run into to look for. The blade at the end when it was real bad wouldn't even rev up on a stand.