09 Nytro 153" bone stock besides a hartman clutch kit. The kit is designed for a 280lb rider in gear, 162 track, 19t top gear, and aftermarket exhaust. I had the clutch kit installed but I haven't switched out the chaincase sprocket yet. I am taching at 9-9.1k rpm's now on flat land but and around 8.9 climbing but my track speed is around 30-35 mph's. I thought I heard you were supposed to be getting around 45 on the hill. What are my options. I realize that my clutching is off for what my current setup is (going to throw the other stuff on this summer) but if anything I would think my track speed would still be higher. Any thoughts?
Thanks, -Justin
Sorry about bringing AC into this. I read the following from Kelsey and it makes sence no mater which brand you ride. Just something to think about. My M7 140 HP Climbing track speed is 48 mph last year.
The whole "Power to the ground" reference is very misleading... Clutch kits really do not put power to the ground.. You have X amount of Power at the crankshaft.. You transfer this power via belt, clutches, and gear-box to the track.. There are inherent power losses associated with this transfer due to mechanical losses of the components involved.. The components are still the components..meaning.. you are still using the same primary clutch, same belt, same Diamond Drive, and same secondary clutch.. So, the components do not change.. What changes is how effectively and efficiently you use these components.. If all the power transfer losses via these components were "ideal" you would have 100% power transfer.. But they are not and there are losses..
So, where does that leave you??
Let's break down the losses in VERY SIMPLISTIC terms...
1) Primary clutch.. Works great and will get the job done in terms of squeezing the belt.
2)Secondary Clutch, also works fine..Shift gets stalled due to the massive spring they use...also has a large tendency to lose belt grip. Which brings us to the the main culprit in the loss dept. BELT!
3)BELT.. This is the real player.. If your belt is slipping, you created more heat and less "grab" on the clutch sheaves and this will lessen track speed.
The key is to have the belt grabbing well AND to have the shift ratio in the MAXIMUM ratio available for ANY given instance (hill climbing, racing etc.) THIS is what is really determining how fast you are spinning the track!
So, all this HP tothe track thing is really not about track HP but more about track speed! and belt heat.. So HP is really not the right term IMO..
The key to having higher track speed is to be in a higher "gear" via your clutches.. ANYTIME you are spinning the track faster, you are in a higher or lower depending on how you look at it) shift ratio from the primary clutch to the secondary clutch. You can NOT increase track speed and still be in the same shift ratio via clutching components changes alone.. 50MPH is 50MPH regardless of what is in either of your clutches. The belt is fixed length and the shift ratio will be the same regardless of what spring, helix, weight etc, you have installed.
So, the real task is to make your track do 60mph when the others are doin 50mph.. to accomplish this you MUST be in a higher shift ratio.
So, no matter if you have 140HP or 200HP if your clutches stall the shift at 50MPH you are only going to do 50MPH no matter how much HP your engine has..
This is where the DD kit , we offer, comes into play.. We find the stock secondary to stall the shifting. This will not allow you to reach the speeds you desire..
With our kit, we change the way the secondary handles the load and make it NOT STALL the shift.. So, this will ALWAYS translate to higher track speeds .
Belt heat is the other "player" You MUST keep the belt slip to a minimum.. With a slipping belt you cannot achieve optimum speeds.. So, the clutch components will be a big player on how much belt slip you experience.
I need to sit down and write this in more specific terms and will dothat soon.. But, for now, I hope this made some sense..
Kelsey
