What are you seeing for RPM?

[Bradford]

I should have addressed this under warranty but....oh well

If I mash the throttle out of the hole or at 50 mph, my RPM goes to about 8900. My top speed on the dream-o-meter is about 100 mph on hard pack at 8900 RPM. What are you guys seeing? Any suggestions for setup? I don't have a lot of interest in going after market, I just want to get my RPM's in line.

Thanks!
Brad.

 

[theCATman]

That's about right. With a worn belt mine would rev to 9,500 But now with a new belt mine revs to 9,000

 

[dox06]

RPM

06 Nytro with 875miles

On hard pack I run about 9000-9300 and as you say the "dream-o- meter" I see 110....

On snow that is another story. I see speeds of approx 97-99 and run the same RPM's

 

[pro116]

It should be running 8600rpms.
Add some heavier rivets to the tip of your weights.
You will see and increase of accelleration,more mph,and better fuel milage.

 

[Bradford]

It should be running 8600rpms.
Add some heavier rivets to the tip of your weights.
You will see and increase of accelleration,more mph,and better fuel milage.

Hey pro116

Where can I get more info on heavier rivets? Is this a trial-and-error thing?

Brad

 

[BonelNytro]

and also what do you use for rivets

 

[pro116]

There made by Ymaha go under the main page and click on tech section it shows you specs break downs and part #'s.

 

[Bradford]

Ok, here's what I found out. The Nytro comes stock with 2 rivets per arm. Both are PN. 90261-06034 @ 3.6g weight. I'm replacing the tip weights with PN. 90261-06033 @ 4.5g. If this doesn't give me what I want, I'll replace the rivets with stock ones and try a Vector primary clutch spring. Stock spring is "green-silver-green" PN. 90501-582L2-00. The Vector spring is "yellow-silver-yellow" PN. 90501-582L1-00. The main difference is the Vector spring has a lower spring rate.

I'll report on my finding as soon as I can.

Brad.

 

[Bradford]

Here it is....

With the stock weights, I was seeing 8900 RPM any time I mashed it. With the new tip weights I'm seeing about 8200 out of the hole and it creeps up to about 8700 or so. Thoughts??

Brad

 

[Turk]

You have to either run it against a timing system or another sled before & after you made the changes to see if performance increases. You need a baseline to compare against.

 

[rxwhopper]

i know topgun on here tried to add tip weight on his to bring rpm down and it got slower. he ended up taking it back out

 

[pro116]

I have had a sled on timers mabe all the tachs arean't accurate.The sled was fastest coming out at 8400rpms and rising 8600rpms.8600 was the sweet spot anyting over or below would be slightly slower.

 

[Bradford]

You have to either run it against a timing system or another sled before & after you made the changes to see if performance increases. You need a baseline to compare against.

Well.... my baseline will be a 600 REV that I lost to last weekend He took me out of the hole but I could take him if we started at 30 mph. We'll see what happens.

 

[IFlyEm]

I've taken every 600 I have run out of the hole. I would get a 2 - 3 length lead then we would pretty much run the same gap the rest of the run. I am seeing 8,500 - 8,700 RPM and have 500 miles on the sled.

I am REALLY kicking around the idea of doing a 128" Apex RTX with a MPI blower. Just a thought

 

[BlkNytro]

Groomed trail: 100mph
100% ice on lake: 110mph
The RPM #'s are very similar...