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Losing RPM and not holding normal top speed

Well I went out and tested it. I'm a little low on rpm, not to low though running around 8500 give or take. I was around 1000'-1200' I didn't measure however I did take my truck down there and it's pretty close to .2 miles so under a 1/4 mile. And from a dead stop I got 106mph I did that three times going the same direction and 106mph every time. I went to another spot where I have no idea how long it is. But I held wot for a slow ten count and I reached 109mph. On a regular snow covered trail. It's not a mile cause the number didn't change on my mileage. So I was pretty happy with that. I will try and get around 2-3 hundred r's out of it. Maybe changing the helix back to what I had. Oh and I DONT like the new colors, so I'm glad I got a 2014!! :Rockon:
 

That's not terrible for your machine but I still feel its 8 or so MPH off the pace of what it should be which is huge really in a trail sled. You need to see 9000 rpm for it to really sweat your leaving a lot on the table yet.
 
TurboJamie said:
That's not terrible for your machine but I still feel its 8 or so MPH off the pace of what it should be which is huge really in a trail sled. You need to see 9000 rpm for it to really sweat your leaving a lot on the table yet.
Click to expand...

Ya I was going to put the helix that I had in there. That was allowing me to go just past 8990 rpm. That's better than now. But it was only 1000-1100 feet. So I was pretty happy with that. And with 4-500 more rpm I should be right there. I do however have a 1.6 lug ice ripper track so that would slow me down a little. Maybe two mph or so maybe three. No big deal to me. I mean really there is no trail around here or any that I know of that I could get much past 90 or so. Most trails except rail road beds don't have that long of straights. I have plenty of mid range! Plenty!! :die
 
Ok , after a day of clutching with the xs805 , got the rpm's right at 8850 then on top end it will go to 9000 , so got the clutching good but I lost 10 mph or more on top so I checked the belt in the secondary and it's not fully shifting out ( not going down in clutch all the way ) so I'm going to get a gates belt that is made for this sled .
So Tim ,
I think you are leaving a lot of mph on top because of the longer belt because you aren't getting full shift so I would get a gates belt and get your clutching figured out , my clutches are running cooler to but the 10 mph or more on top isn't going to cut it , best I seen on speedo was 82 mph
 
09nytro said:
Ok , after a day of clutching with the xs805 , got the rpm's right at 8850 then on top end it will go to 9000 , so got the clutching good but I lost 10 mph or more on top so I checked the belt in the secondary and it's not fully shifting out ( not going down in clutch all the way ) so I'm going to get a gates belt that is made for this sled .
So Tim ,
I think you are leaving a lot of mph on top because of the longer belt because you aren't getting full shift so I would get a gates belt and get your clutching figured out , my clutches are running cooler to but the 10 mph or more on top isn't going to cut it , best I seen on speedo was 82 mph
Click to expand...

Longer belt? Longer belt = less mph
 
I just wanted to try it , but sitting on the couch thinking about it last night it rang a bell and I said that's way I'm not seeing the mph I was , O-well had to try it !
 
I just put a 8DN on mine. What a difference a belt makes.

My sled actually feels like it has a turbo now. RPMs pull to the 9000 and stay there. I actually need to load up a bit more weight cause it is pinging rev limiter. Never did that before.

It was nice to drive it and the RPMs were not shooting up to 9000 then down to 8000 and back up. Clutches were much cooler and could touch them now. Before they were to hot to touch.

I was still able to pull 95 mph on my dash with the 162 track. Would rarely see that before as most of the time it would do 87 mph.

I am going to stick with the 8DN.
 
loudelectronics said:
I just put a 8DN on mine. What a difference a belt makes.

My sled actually feels like it has a turbo now. RPMs pull to the 9000 and stay there. I actually need to load up a bit more weight cause it is pinging rev limiter. Never did that before.

It was nice to drive it and the RPMs were not shooting up to 9000 then down to 8000 and back up. Clutches were much cooler and could touch them now. Before they were to hot to touch.

I was still able to pull 95 mph on my dash with the 162 track. Would rarely see that before as most of the time it would do 87 mph.

I am going to stick with the 8DN.
Click to expand...
Did you shim the secondary clutch at all
 
Right on !
I had three 1mm washers in , and you got 95 out of it that great !
Put stock belt back on and played with clutching all day and could only get 87 out of it , but the trails are fresh groomed !
 
I must say after playing around today may rpms are better with the xs805 belt then with the stock one
With the stock belt my rpms are all over not by much (100,200+,- ) but still up and down never could get it to stay at one rpm

With the other belt I could , come right out of the hole at 8750 then go to 8900 .

With both belts could only get mid 80's out of it , but I was also testing on a groomed trail so maybe that had something to do with it
 
Im up north MN and there is a fresh 5 to 6 inches and I had no problem getting 105 mph on the straights. But I tipped it over today on the left side and spilled some oil on it. So I got nervous for a sec. But its all good now. But I think the the clutches are pretty close.
 
Is it safe to say that the Viper belts are not made of the same material that the old 8DN belts are? Can those that have tried this belt list if they have done anything else to the secondary?
 
The belts are physically different. The 8dn has more cooling ribs.

My clutches were unchanged between belt changes. I did not even shim the secondary. The 8jp sat just below top of secondary and pulled tight on primary. The underside of the belt was wearing from primary shaft. No deflection. The 8dn has some deflection and sits a bit 1.5 mm above secondary. This is right on spec with manual.

I have different clutching than stock. I use gwg spring and 8bu weights with white spring and 37* helix clocked 80. This is to spin my 162.
 
Low RPM's and top speed

Can anyone tell me how many RPM's I should be running at full throttle. I'm running between 8300 and 8500 at full throttle. Very low top end couldn't get anymore than 80 MPH on groomed trail. I also have a 2012 Nytro backcountry. I got smoked on my viper by my dad riding my Nytro. Went by me like I was standing still. I have 900 miles on my viper LTX belt. My Nytro has 2200 miles on the belt. How do I get more top end. If I wanted to ride 80 top speed I would have bought a Phazer.
 
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