Setting the World s Performance Standards Twin Pipes for 2004 Arctic Cat 900 Mountain Cat Twin P.N. 09-907(CP) Contents of Pipe Set 1 - Plastic Zip tie 3 - Large Head Rivets 4 - Short s 1 - Red Silicone Vibro-Support Assembly 1-1/4 x 1 1/4 x 20 Bolt 1-1/4 x 20 Lock Nut 1-1/4 Flat Washer 2 pc - 240 Reflective Heat Tape 1 - Flange 1 - PTO Pipe (P.N. #090-9072) 1 - MAG Pipe (P.N. #090-9071) 1 - Silencer (P.N. #090-9073) 1 - Outlet Plate (P.N. #090-907) 2 - Grafoil Gaskets Installation Instructions IMPORTANT: Read instructions carefully before installation. 1. Remove stock exhaust, Y-pipe, silencer, and outlet deflector. 2. Install flange plate onto cylinders using stock flange studs and tighten using stock nuts. 3. Unclip hood cable from the hood. Remove screw attaching cable to the bulkhead. Measure from this screw hole towards the PTO side 2, mark and drill a new hole using an 11/64 drill. Use stock self tapping screw to reinstall cable to the bulkhead (see illustration #1). 4. Remove stock rubber pipe support located on the mag side shock tower. Relocate the rubber support to bulkhead by measuring from the front side of the shock tower support crossbar towards the front of the sled 2 and mark. Place the rear edge of the rubber support on the mark, then mark and drill two 3/16 holes and rivet into place with 2 large head rivets provided (see illustration #2). Note: When reinstalling the rubber support make sure that the raised side of the support is towards the center of the sled. 5. Remove stock spring tab located in the front of the bulk head and relocate to the existing hole located 5 1/2 in from the front PTO corner of the bulk head (see illustration #2). 6. Cover shock tower and area on the side of the belly pan closest to the pipe and silencer with reflective heat tape (provided). Cover the PTO shock tower in areas closest to the pipe with reflective heat tape (illustration ). All of the wires and CDI Box located behind the silencer will need to be covered with reflective heat tape. 7. Relocate coolant bottle to the inside of the oil bottle next to the CDI bracket (see illustration #4). 8. Remove all foam from the right side of the hood and replace with reflective heat tape (illustration #5). Use the zip tie provided to tie the exhaust valve cable to the mag side cylinder exhaust valve vent hose (see illustration #6). 9. Remove stock silencer support bracket from chaincase. 10. Run a bead of silicone around the ouside edge of the outlet deflector plate and install to belly pan from the bottom of the sled and bolt into place using the stock bolts (see illustration #7). Using a plate as a guide drill a 3/16 hole in the back of the plate and rivet into place. Optional Deflector Installation: Stock snow deflector can be reinstalled just forward of the exhaust outlet drilling new holes and riveting into place. 11. Install spring tab provided using the upper front chaincase cover bolt. Place the spring tab in the 12 o clock position (see illustration #8).
11/12/03 09-907(CP) Page 2 12. Run a bead of silicone around the bottom edge of the silencer outlet tube (see illustration #9). Set silencer into place and bolt the front of the silencer to the stock silencer support using vibro-support with the 1/4 bolt provided (see illustration #10). Place one stock rubber mushroom into the bracket at the rear of the silencer and spring into place. 13. Install Mag pipe (pipe with logo) and spring into place with springs provided. Then install PTO (pipe without logo) pipe and spring into place with springs provided. PTO pipe to the stock spring tab in the front of the bulkhead. Note: Check the tightness of the clamps located in the midsection of pipe approximately every 100 miles for the first 300 miles then periodically after that. Tension Adjustment: loop adjustment is suggested for proper spring tension to prevent leakage and wear (low tension), allow adequate flex (proper tension) and prevent spring breakage (excessive tension). When system is installed the spring can be judged for proper tension. The winding spacing at the center of the spring will indicate tension. When proper the two center windings will have.040" to.050" clearance between them. This is easily tested with a feeler gage. If tension is incorrect, the loop on the pipe or silencer can be bent in the direction needed to increase or decrease tension. Attach a vise grip firmly to the loop and bend. Caring for your ceramic coated pipes and/or silencer: Ceramic Coating is an aluminum matrix applied to your exhaust system to provide a thermal barrier for more consistent performance. It is a coating which requires little maintenance to keep your pipes and/or silencer looking like new. Upon completion of new installation, wipe the ceramic coated parts of the exhaust system down with brake cleaner. This will prevent oils and grease (usually in the form of fingerprints) from burning on and staining the exhaust during first initial startup. To maintain your ceramic coated system, wash it with soap and water periodically (especially necessary after trailering it to and from your riding area on roads that have been treated with salt and other ice removing chemicals). Salt and other ice removing chemicals will attack and eat away at the ceramic coating. This will result in rust coming through the coating. Typically you will notice this rusting after your snowmobile has set for a period of time without the exhaust system being brought up to running temperature. Periodically polish your ceramic coated pipes and/or silencer after each washing with an aluminum polish such as Mothers, Maas or Blue Magic aluminum polish that can be found at any automotive parts store. Do not use any acidic cleaners! For stubborn stains use fine 000 steel wool, then use a soft cloth with polish. Failure to maintain your ceramic coated pipes or silencer can result in damage to the ceramic coating for which there is no warranty coverage. A little care will insure that your pipes and/or silencer will continue looking like new for many years. Note: In areas of the ceramic coated system where skin temperatures exceed 1300 degrees F, it is normal for the coating to turn dull gray. These areas should also be washed and polished periodically.
11/12/03 09-907(CP) Page 3 Jetting Arctic Cat 900 Mountain Cat with Twin and Stock Air Box Altitude -40 to -20 F (-40 to -29 C) -20 to 0 F (-29 to -18 C) Temperature 0 to 20 F (-18 to -7 C) 20 to 40 F (-7 to 4 C) PTO/MAG PTO/M AG PTO/M AG PTO/M AG 0' (0m) 500/540 490/500 480/490 470/480 2000' (610m) 470/480 460/470 450/460 440/450 4000' (1219m) 450/460 440/450 430/440 420/430 6000' (1829m) 420/430 410/420 400/410 390/400 8000' (2438m) 410/420 400/410 390/400 380/390 10,000' (3048m) 400/410 390/400 380/390 370/380 +12,000' (+3658m) 390/400 380/370 370/380 360/370 Note: If shelf is removed from airbox or if using an Air Intake Kit, increase main jet one size from chart * See Fuel Requirement note on the next page. Altitude Pilot Screw Pilot Jet Needle Jet Jet Needle 0-3000' (0-915m) 3-5000' (915-1524m) 5-9000' (1524-2743m) +9000' (+2743m) 1 ½ Turns 50 Fixed 9DFH2-59-4 2 ½ Turns 50 Fixed 9DFH2-59-4 2 ½ Turns 50 Fixed 9DFH2-59-3.5* 2 ½ Turns 50 Fixed 9DFH2-59-3 * Use P.N.14-254 0.020 needle shim under e-clip Needle Position with E-clip and shim washer E-clip 0.020 Stainless Steel 1.5 shim washer 2.5 3.5 (P.N. 14-254) 4.5 5.5 E-clip Position 1 2 3 4 5 Leaner Richer IMPORTANT NOTE: CARB TUNING SPECIFICATIONS INCLUDED IN THIS SECTION ARE A BASE LINE AND SHOULD BE ADJUSTED AS NEEDED FOR YOUR PARTICULAR ATMOSPHERE. USE EXHAUST GAS TEMPERATURE GAUGES OR MONITORING PLUG AND PISTON COLOR FOR TUNING GUIDE. Fuel Requirements: 0-3000 : Mountian Cat: Race/premium blend of 1 gallon of 108 motor octane race gas to 4 gallons of 91 octane pump fuel. 3000 +: 91 octane pump fuel Spark Plug Recommendation: BR9EYA Important Note: Fuels containing ethanol, alcohol based fuel compounds, or oxygen carrying additives will require larger main jets, usually 2 sizes more than the jetting chart. Jet Needle may need to be raised one E clip position. Also recommended is the use of an High Flow Outside Draw Airbox Conversion Kit. This effectively transforms your stock intake system, allowing more cold air to reach the engine which translates into an increase in horsepower. This system is also less likely to plug when riding in deep snow conditions. Conversion Kit #14-208 2003 Mountain Cat #14-261 2004 Mountain Cat
1/26/05 09-907(CP) Page 4 Arctic Cat 900 Mountain Cat with Twin Pipes and Air Box using BoonDocker Performance Control Box Important Note: The following information is given as a guideline only. The fuel map listed was attained using an Arctic Cat 900 Mountain Cat with twin pipes and air box. Fuel used was premium 91 octane non oxygenated. recommends that you start at a richer setting than what is listed below and lead down as needed for best performance using plug color and piston wash as a guideline. Exhaust temperature gauges can also be used as a tuning aid, but due to differences in gauges, probes, probe position as well as many other engine variables you must first establish a relationship between plug color / piston wash and exhaust gas temperature. Fuel: Minimum 91 octane pump fuel. Fuels containing ethanol or oxygen carrying additives will require more fuel than non oxygen carrying fuels. Fuel Map for Arctic Cat 900 Mountain Cat RPM Low Mid High Trim 3000 00 00 00 00 5000 00-10 -13-08 6700-01 -15-16 00 7800 02 15 23 01
12/16/03 Clutching for Arctic Cat 900 Mountain Cat with Twin Pipes (Models with 9 Tower Clutch) Altitude Arctic Cat Cam Arm (Good) Drive Clutch MTX Cam Arm (Best) 09-907(CP) Page 5 Torque Bracket Stock Driven Clutch Overdrive Helix TEAM Industries Driven Clutch Torque Bracket Gear Ratio 0-3000' (0-900m) 0746-640 71.5 g Yellow/Blue #40-70 57/50º #0648-016 Red/White 26-41 ZR 20-41 MC 3-6000' (900-1525m) 0746-650 67g #40-83 2 g rivet in and 1 g outer hole 55º #0648-005 Red/White 70/48 6-9000' (1525-2743m) 0746-614 64g #40-83 1 g rivet in and outer hole 47º #0648-025 52-60/47 or 53-60/47 Yellow 70/46 Above 9000' (Above 2743m) 0746-615 62g #40-83 1 g rivet in hole Running RPM 8000-8200 47º #0648-025 52-60/47 or 53-60/47 Yellow 70/46 Clutching for Arctic Cat 900 Mountain Cat with Twin Pipes (Models with 6 Tower Clutch) Altitude Cam Arm Drive Clutch Torque Bracket Stock Driven Clutch Overdrive Helix TEAM Industries Driven Clutch Torque Bracket Gear Ratio 0-3000' (0-900m) Arctic Cat 0746-710 72 g Yellow/Blue #40-70 57/50º #0648-016 Red/White 26-41 ZR 20-41 MC 3-6000' (900-1525m) #40-95 2 g rivet in and 1 g outer hole 55º #0648-005 Red/White 70/48 6-9000' (1525-2743m) #40-95 1 g rivet in and outer hole 47º #0648-025 52-60/47 or 53-60/47 Yellow 70/46 Above 9000' (Above 2743m) #40-95 1 g rivet in hole Running RPM 8000-8200 47º #0648-025 52-60/47 or 53-60/47 Yellow 70/46
Illustration 1 Illustration 2
10/30/02 09-907(CP) Page 7 Illustration 3 S`od S`od Illustration 4
10/30/02 09-907(CP) Page 8 Illustration 5 Replace Foam with Heat Tape Illustration 6 Zip tie VES cables to vent hose
11/12/02 09-907(CP) Page 9 Illustration 7 Illustration 8
11/12/03 09-907(CP) Page 10 Illustration 9 Illustration 10