Clutch RPM

[nitris223]

I was out riding my sled this weekend and had a chance to get on a fresh groomed trail to check out what RPM my 162 nytro mtx is running at w.o.t. Most it will pull is 8850 on a long stretch. With the Hindle exhaust I was told I should be around 9200. What do I have to change to get the extra 400 rpm. Here is my clutch set up.
OPO primary
14.5 rollers
stock weights loaded with the heaviest steel rivets in the rear and middle hole and steel rivet with hole in the tip.

Secondary spring is stock at 3 and 3 twist
belt ribs are just above the top of the secondary sheave.
Gearing is 20 / 40 but I will be going back to 18 / 40.
43* helix

It seems to pull nice but just missing a few rpm's on the top. Do I need to be a bit lighter in the tip of the weights or will the 18/40 gearing help bring back a bit of the rpm on top.

 

[mx1500]

yes, clutch is stock with full mbrp system. still cant get more than 85-8600rpm outa it. it feels like it bogs, or the throttle isnt wide open, ya kno?

 

[HYFLYR]

Do not clutch it for 9200rpms!!!! Max would be 89-9k but I myself prefer 888-8900, turbo or not. The oil pump on these motors will not live at 9200 and will start to foam the oil and you will lose the center rod bearing. I have motors to prove it.

 

[nitris223]

So it sounds like my clutching is good. I will see if it changes any with the top gear change.

 

[Daranello]

Mine ran best at 9250 on ice...in snow 8900 was were I liked it. But for crazy top end it needs to be above 9

 

[jonnytro]

Mine ran best at 9250 on ice...in snow 8900 was were I liked it. But for crazy top end it needs to be above 9

. Yup same here

 

[shadow44]

I was out riding my sled this weekend and had a chance to get on a fresh groomed trail to check out what RPM my 162 nytro mtx is running at w.o.t. Most it will pull is 8850 on a long stretch. With the Hindle exhaust I was told I should be around 9200. What do I have to change to get the extra 400 rpm. Here is my clutch set up.
OPO primary
14.5 rollers
stock weights loaded with the heaviest steel rivets in the rear and middle hole and steel rivet with hole in the tip.

Secondary spring is stock at 3 and 3 twist
belt ribs are just above the top of the secondary sheave.
Gearing is 20 / 40 but I will be going back to 18 / 40.
43* helix

It seems to pull nice but just missing a few rpm's on the top. Do I need to be a bit lighter in the tip of the weights or will the 18/40 gearing help bring back a bit of the rpm on top.

Who told yout that? While the Hindle system will make peak power that high...there is no need to spin it that high. Peak power with this system starts around 88-8900 and stays their until 91-9200. I found my best clutching ran at 9050 max....that seems to be a sweet spot for this system.

 

[mx1500]

yes, but mine doent get that high, it used to

 

[nitris223]

Don't remember who told me 9200 off hand, but I thought I read it somewhere on here that 9100 9200 was where it needed to be clutched. Just off the rev limiter. Going to leave it at 8900 and just ride. Next thing you know my panels will be falling off on their own . I have had them off and on so much over the last few weeks, I am going to wear out the holes. lol.

Now I just have to test the hindle system against my buddies mbrp system. Not a apples to apples test because his is a XTX and mine is a MTX 162. Would be nice to know how well the auto tune is making HP compared to the map that came with the PCV.

 

[nitris223]

Changed out the top gear on both sleds this week, put the stock 18 tooth back in. My 162 with the Hindle exhaust picked up some RPm. 9100- 9050 then drops to 8950 on the hard pack stuff. My wife's 153 sled on the other hand with only a super Q exhaust hits the rev limiter by 75 to 80 mph. Now I either add some rivets to the weights or put the 20 tooth back in. With the 20 tooth it never hit the rev limiter. If I do the weights now I have to figure out what rivets for the right RPM. I tried hers and seen 9500 for asplit second but I think the limiter is at 9400 rpm isn't it.

 

[shadow44]

Changed out the top gear on both sleds this week, put the stock 18 tooth back in. My 162 with the Hindle exhaust picked up some RPm. 9100- 9050 then drops to 8950 on the hard pack stuff. My wife's 153 sled on the other hand with only a super Q exhaust hits the rev limiter by 75 to 80 mph. Now I either add some rivets to the weights or put the 20 tooth back in. With the 20 tooth it never hit the rev limiter. If I do the weights now I have to figure out what rivets for the right RPM. I tried hers and seen 9500 for asplit second but I think the limiter is at 9400 rpm isn't it.

9400 is where the rev limiter is. 9050 with the Hindle system is perfect!