Hardcore Sledder banner
1 - 15 of 15 Posts

·
Registered
Joined
·
72 Posts
Discussion Starter · #1 ·
So, I put a set of SLP twins on my sled, along with the recomended Slp head (12-530 domes, to lower static compression) And it won't rev past 6 grand on the stand. I had the sled running pretty well last year with the Hot Seat single, and all I did was add the twins, and head. I've checked the carbs, reeds, compression (105 both sides) checked the pipes, and can for obstructions, lowered the jetting from SLP's recommended 520N to 450. By that time I was most of the way thru a box of beer, and then I noticed the broken fuel tank neck........ What a great weekend. I had the box reprogramed by Hot Seat, to remove the DET 2 years ago. Anyone have any bright ideas?
 

·
Registered
Joined
·
6,369 Posts
sounds like your exhaust valves are not opening , 6K is about the high a motor will go with them closed. did you clean them? 450 MJ is very lean with twin pipes , I think 480 would be safe
 

·
Registered
Joined
·
6,369 Posts
put your stock head back on and see how that runs. the orings are reuseable and long as they dont have nicks in them. 105 is very low , 120~130 is normal with twins and stock head could put you around 140.
 

·
Registered
Joined
·
2,170 Posts
450s are way to lean for those pipes on that sled at sea level. FWIW, my buddy burned his down a -5F with 500s in it during a 1/2 mile run. Do you have the carb vents plugged into the airbox? Bypass the temp sensor and try it again.
 

·
Registered
Joined
·
392 Posts
double check the temp sensor and wiring harness to it. By changing the routing of the pipes, you may have heated the harness causing a short.
 

·
Registered
Joined
·
297 Posts
Now this might sound stupid. Check to make sure your headlite is working. My 02 800xc would not go past 6000 rpm. Dimmer switch was bad and low beam didnt work. Got both beams working rpms back to normal. Dont know why or how even polaris couldnt explain it, although they have heard of it. Good luck
 

·
Registered
Joined
·
2,344 Posts
COME TO THINK OF IT MINE DID THAT AS WELL WITH THE UPDATED VALVES AND STOCK SPRINGS. I GOT UPDATED VALVES WITH NEW SPRINGS AND WORKED OK FIRST YEAR. SECOND YEAR I TRIED THE STOCK SPRINGS AND IT WOULDNT PERFORM WELL. HAVE THE VALVES BEEN CHANGED. IT WAS A KIT WHEN I GOT MINE. VALVES SPRINGS AND BELLOWS.
 

·
Registered
Joined
·
6,567 Posts
If 105 lbs. compression is all it has when you pull it over until you have the highest reading, that is way too low. Of course on a gauge that is known to read properly. I would run around a 470/480 main if at sea level. As mentioned, do not expect it to rev out on the stand. Something to try would be to remove the ves springs, and see if it revs out. If it does, you have too low of cyl pressure. The green/yellow springs should be fine at sea level.
 
1 - 15 of 15 Posts
Top