21/38 gearing on extended Apex

[Maurizio Benelli]

Ok now that we know what your looking for we can help you out. So you are looking for a smooth engagement and top end really does not matter. If thats correct what is the rpm where your primary engages now.

About 3500 rpm. About 95 mph is all I need, anything above that is unnecessary for me. I live next to a big lake, but some people think my sled is speeding even
when it´s stationary and they write angry messages to local newspaper

 

[Sled Dog]

I would think a softer primary spring may be all you need and a good place to start. Try the orange silver orange that grader suggested and let us know how it works out for you.

 

[Maurizio Benelli]

I´ll try that. We don´t have snow until december, so I won´t be doing any thorough testing before that

So I´m going for 22/38, orange silver orange spring and 2" lug track. If I sell enough a** before winter I might buy a clutch kit from Ulmer.

 

[sherlock29]

remenber... once past the 23/38 gear..ie: 22/38 you need 68link chain.

24/38 stock gear requires 70link
23/38 requires 70link
22/38 requires 68 link...

just a heads up!!! dont want to have a chain let go and take out alot more...

 

[Shiek]

springs

Pretty sure you want the orange-pink -orange preload is 30
orange-silver - orange is 35 preload

 

[Maurizio Benelli]

So, now I´ve ordered 22 upper gear, 68L chain, orange-pink-orange AND orange-silver-orange springs. We´ll see which combination works better for me. Of course it´s possible I need more changes on clutching.

 

[sledneck22]

I have 22/40 from 20/40 stock. on my MTX which i use about 50/50 on/off. However it left my RPMs on trail too high still. My clutching was the stock MTX weights which I wouldn't recommend. I have DnF weights which I am actually going to install tonight to take care of that. I would be able to post a little better results when the snow actually flies but I do like the gearing setup.

 

[Maurizio Benelli]

Well, orange-pink-orange didn´t do jack to engagement rpm. It still engages at 3500 rpm. Could this be due to worn belt? I´m still sporting the original one and it has almost 5000 miles on it.
Also the acceleration seems to be kinda sluggish, it doesn´t feel very sharp.

 

[blade072]

I bet there´s couple of topics on this matter, but I can´t find any.

So, I´m thinking of 21/38 gearing on my Apex ER (extended to 144"). Will I nee a clutch kit/new settings in clutch? Will it over rev or something?

I went with a 22/40 on my 07 Attak GT. I softened the primary spring to lower RPMs at engagement. I was trying to hook the track up better. I also had a Cobra track. You then need to get the 2011 Apex weights and load them heavy. The RPMs were in the 10,600 range. I like to lug the engine a little instead of over revving.
This combo worked super good and never hurt gas mileage. We had compared gas mileage several times with my buddys Attak. The performance was much better. Top speed wasn't there which I am not a lake racer. It also seemed to help loading on the trailer. If I remember, you can use the stock chain with this gear combo. I am now riding a 2011 Apex XTX and everything is stock as I only have 800 miles on it.

 

[the kitchen]

I am currently running the 21/38 gears on my 06 attak which is two gears down from stock 23/38. I had the clutches cut for overdrive and run heel clicker two speeds for weights loaded up heavy to hold rpm's where I need them. I would never go back to stock gears as the pull is so much more its like I added 20hp. I pulled it across the lake and still found 122 speedo which is about 106 gps. Stock weights will be harder to adjust by just changing the spring. You should consider a clutch kit as tuneing will be simplified and performance will be gained. Your current gearing with 8t drivers is the same as 21/38 so do not go lower than youare now.

 

[Maurizio Benelli]

So now my current setup is this:

22/38 gearing
8T extros
144" track with 2" lug
Orange-pink-orange primary spring
I´ve managed to shave off about 33 pounds with new exhaust and seat

Yesterday I saw 110 mph on the speedo and GPS recorded 92 mph. This 92 mph is pretty much what I´ve been aiming at, so I´m satisfied with that.
At full throttle I´m revving 10800 rpm, isn´t that too much? How can I get this down?

 

[sledneck22]

rpm

Your max HP target RPM is 10800 on the apex so you are perfect.

 

[Maurizio Benelli]

I thought it´s 10400, but if it´s 10800 then I´m glad!

 

[granto211]

This sounds like a world of mess.

 

[Maurizio Benelli]

Check out this video of my sled and tell your opinion does it sound kinda sluggish? Shouldn't it rev better than this? It chokes for a second when I "floor" the throttle.
I know the pipe before muffler is too small. Also don't worry about the taillight wires, they've been taken care of

YouTube Apex idle