Only hitting 8000 RPMs with stock clutching.

[philsummers21]

Local tobacco shops usually have decent ones for around $30. With a stiffer secondary spring or even more Degree twist you will also pick up a few RPMS.

 

[dfinn]

How do you adjust the twist on the secondary spring?

 

[philsummers21]

take off the 3 12mm Nuts. There is a 1, 2, and a 3 on the clutch and a 0, 3, 6 on the plate. Add the 2 numbers and thats the degree of twist. 0-1 is 10 degrees. 3-3 is 60Degrees 6-3 is 90degrees and so forth. If your running the stock secondary twist it up to 90 degrees.

 

[dfinn]

Extremely helpful Phil. Thanks again.

 

[NytroLou]

I have a scale that I use for reloading shotgun shell. It measures in grains which is a more acurate measure than grams. Like Phil did I shot for 63.00 grams which is 972.24 grains. The multiplier is .064798918. I was concerned with maintaining the balance of the clutch.

Phil, thanks for the secondary advice.

 

[philsummers21]

np. You must reload some wicked shells. my scale only went to 500grains.

Ah just read shotgun shells

 

[NytroLou]

My scale goes to 1,000 grains.

 

[dfinn]

Weights were at 63.8 so I took them down to 63.2. I'll test this weekend and report back.

I took the secondary apart to change the spring tension. I'm a little confused. Here's a pic of my secondary:

There's no number markings on the clutch plate itself where the inside of the spring goes to. I've got a 0,3,6 and 9 on the outside. I'm not quite sure how this should go as it doesn't look like it fits Phil's description.

 

[philsummers21]

ok on that you have 0 3 6 9. on the clutch you will have 3 more holes where the other side of the spring goes. they will be marked with a 1 2 or 3. The ones on the cluch are very hard to see as but if you look you can make them out. Once i determined them i used a punch and put 1 dot on 1 2 dots on 2 and 3 dots on 3. But anyway put the one end of the spring in 9 and the other in 0 and that will put you at 90degrees twist. Did you happen to see where it was at stock?

 

[philsummers21]

in fact id probably run it at 120 degrees. 9 and 3

 

[DamonJones]

I was told that RPM's should be controlled by the primary not the secondary. And to dial it in first then adjust your secondary for shift characteristics. I believe that came from Hartman.

 

[akvector]

wind your secondary spring to 6-3 or like phil says put the yellow cat spring in. i have tried the cat spring yet but i would like to put a multi angle helix on.

 

[NyTrOMaNIaC]

phil, what would you recommend for a 2010 MTX SE 153, ridden from sea level to 2000' with Yamaha's recommended adjustments (22/40 gearing and the sea level kit) ? I spoke with my dealer recently because I was only seeing 8500 rpms in soft snow, and he said to be patient and take note once the engine gets fully broke in, or to try putting more tension on the secondary spring as you mentioned in detail earlier.

Appreciate your input

 

[..SNAKEBIT..]

riding in Iowa
Excell Vector header and Micron silencer
stock primary all rivets removed and Yamaha 47 helix with pink spring @ 3-3.
seems to be working good turning 8800-9000
will climb a little over 9000 on longer trail straights

 

[philsummers21]

Yeah no clue on the lower elevation. Im no pro on clutching thats for sure. I agree you should only get your RPMS with the primary, BUT messing with the secondary adjustes RPMS as well. Id rather get my backshift where i like it then get my RPMS where they need to be. On these Nytros i wouldn't bother with clutching till you have some miles on them tho or you will be chasing with your clutching. at 500miles see where your at. But that being said i think stock the nytros backshift was horrible.