DRIVE SYSTEM INSTALL NOTES ON SPROCKET INSTALLATION
(Setscrews loosen which results in sprockets starting to wobble and eventually, they will come off the shaft. You may notice an unusual vibration or an unusual noise at idle. If it comes loose it will cause damage that is not covered under your warranty (including sprockets).
A. Improper tightening of taper lock. It is possible to get 40 in-lbs but have the taper bushing slightly sideways. Once the sled is ridden the bushing / sprocket set will self align, however , if it was not aligned / centered during installation the setscrews will not be tight and the set will “self eject”. If a sprocket / bushing set comes off or wobbles badly, typically neither can be reused
B. Additionally, MPI has upgraded the aluminum in the sprockets from 6061 to 7075. 7075 is much harder and makes a better sprocket, unfortunately it is less forgiving for misalignment on the taperlock. The older, softer aluminum would conform easier to the taperlock. The harder aluminum is a much better product, but is more difficult to keep installed. By following the procedure indicated, you should be able to yield 100% success.
C. Refer to the Taper Lock to Key Gap drawing, Figure 68. Remove any rough edges on the Taper Lock and/or the woodruff key. If the Taper Lock is installed into the Sprocket, remove the taper lock from the sprocket. Test fit the taper lock onto the shaft. Refer back to the drawing to verify that you have the appropriate clearance over the keyway. If there is interference on the keyway, it is best to EVENLY file the keyway in the Taper Lock.
D. Put the Taper Lock bushing into the sprocket from the outside. Start 2 set screws into the holes that are 180 degrees across from each other. About 5-6 turns on the setscrew so that the bushing still moves up and down just a little bit.
E. Slide the lower drive sprocket on as far as possible, and then pull it back out just a bit (0.002” to 0.010”). See Figure 69.
F. Temporarily reinstall & tighten taper-lock set screws to 40 in-lbs in even steps (#1 screw, #2 screw and back and forth until there is no screw movement). Set you alignment as described below in the instructions. It is acceptable to have as much as 1/8” (0.125”) of misalignment, but less is always better. Figure 70.
G. Note the position of the Taper Lock on the Shaft (and PTO), you will need to remove the sprockets and replace them back into this position without spending time to realign them.
H. Once you satisfied with your alignment, remove both sprockets. Reset the set screws into the tightening position.
I. The next steps will be performed individually on each sprocket. Do not heat both sprockets at the same time.
J. We recommend that you do the PTO sprocket 1st. Also, don’t forget that some Sprocket combinations require that the belt be put on with the top Sprocket. You will know this from your test fit.
K. We recommend that you use an electric skillet or electric frying pan to heat the sprockets. This item is available from Wal-Mart or similar for about $20.00. Preheat the frying pan to about 375F (not over 400F). The aluminum can be damaged if it is heated above 400F (but the pan would probably have to be well over 400F to do that). Some pulleys are marked with heat sensitive paint, The paint is on the face and should be facing UP in the pan (and the taper lock should be installed into the sprocket; but not tightened). The goal is to melt the paint.
L. Remove the Sprocket/Taper Lock from the pan and quickly install on the Shaft (or PTO). Tighten taperlock set screws to 40 in-lbs in even steps (#1 screw, #2 screw and back and forth until there is no screw movement). Now increase the torque to 60+ in-lbs. You can go well above 80 in-lbs, but the hex bit is typically the weak link. Snap-on hex bits will twist at around 60 to 70 in-lbs while APEX is the best we have tested. They yield near 100 in-lbs. Once you have finished torquing, and you are sure the set will not move any further, remove the setscrews one at a time and apply RED loctite and re-torque to 60+ in-lbs. Letting the loctite “set-up” or dry for 24 hrs is very important, plan ahead. The installation process (not including the loctite step) should take about 2 minutes. Do all you can to minimize the time from the frying pan to torquing.
THIS SHOULD TAKE WAY LESS THAN 5 MINUTES.
M. Repeat the process on the top sprocket.
Now you know why I'm installing a MCX trubo, sorry things are not so smooth for you Crhis......
