letitsnowmtx
Veteran
I was thinking about changing the stock mtx gears to give me a little more top end. I race the sled in stock 500' drag races on the flat and up hill. I was wondering what else would have to be done to the sled, if anything, and what kind of gains I could expect.
What track are you running and what is your weight.
letitsnowmtx
Veteran
I have the stock track cut down to 1.25" which made a big difference in traction. I also have a barkers exhaust, pc3 and ignition module (not installed yet, I'm going to have to figure out how to program the ignition module), and 4 frogskins on the lid of the airbox. I weigh 210 without gear.
I noticed on my MTX with a 144 X 1.75" Back Country track no difference in top end 75 mph with gear change. 17/41 is stock and the 19/41 I tried and did not have the punch I was looking for. I would say gear up with smaller 121" track but a 144" track is still alot of fling compared to the 121". that being said I weigh 290 lbs with gear and am turning a big fan blade of a track. Depending on the length of what your doing a helix change for faster shift out may be the ticket. Send me a PM if you want to chat about it.
blueironranger
TY 4 Stroke God
- Joined
- Feb 3, 2009
- Messages
- 2,002
- Age
- 45
- Location
- Iron Range MN
- Country
- USA
- Snowmobile
- 2014 Viper XTX
2009 Phazer MTX
changing which way? I know in 500ft with the stock 17t gear I still had speed to spare but would rev out around the 600-700ft mark. The 17t should be good for 70mph GPS before hitting the rev limiter, a 19t is good for around 78mph fully revved out. Mine will pull the 19t gears to redline but it takes well over a 1/4 mile to get there on a hard pack road. You need to change the lower gear to a 45t if you want to go even steeper which requires a new chain also, that will only give you 61.5mph with a 1:1 drive ratio, or with machined clutched for more overdrive (0.9:1), bout' 68mph. Personally I plan on going back to a 17t gear and machining the clutches for more overdrive, which should allow 19t like top speed but keep the 17t torque.
17/45 tooth lower gear does fit I did it this past season. Just put both gears on at same time with chain around them and trim 1/8" off tab on idler to miss case. The chain that was ordered was wrong so I tried it anyway and it worked. Beat the dickens out of my with no issues.
letitsnowmtx
Veteran
In 350' 54 mph (on a radar gun) was my best run. That was with only the exhaust. I have to put on the pc3 and ignition module for next year. I will also have the clutches machined before next year. I beat out a 500cc sno pro in my first heat at the 500' hill climb, but the next heat the sled hesitated bad and I couldn't catch up. So I guess what I am saying is that I know I can make this sled really competitive in drag racing, and still have fun with it on the trail. I know I still have clutch work to do also, but I wanted to have gearing ready, so I wouldn't have to reclutch again.
Also a YVX secondary would be great with way more helix options like a 45 or 47 degree helix. Lower gearing would be better with taller helix. I have 9 tooth drivers and 17/45 gearing with YVX secondary with Hauck Roller and a 43 degree helix. The 43 degree helix with a roller is equal to a 47 degree helix and mine shifts like a rocket to 60 mph.
