ulmer clutch kit question

[rfabro]

Thanx, Gabe. Let us know.

 

[Reaper]

Clutch Kit

Running the setup with 1.5" Freeride and it really pulls hard and feels great ! I did loose a little top end (about 3-5km seems) I am revving at 11,500 but did notice clutches getting hot after long high speed riding not sure how hot they should get. You could but you hand on the face of the clutches for 4-5 seconds but would then start to get pretty hot on fingies ! I wrapped secondary to C2 (20 degrees), think I should back off to C1 (10 degrees). Would this help get back top-end and heat in the clutch ??

I did notice after running WOT for a while revs would fall a bit 11,300 and would not pull as good top end.

 

[Srxspec]

Back off to B1, going all the way from C2 to C1 would be 30 degrees of total adjustment. The secondary adjustment goes as follows:

C-1 = softest
A-1 +10* (stock setting)
B-1 +10*
C-2 +10*
A-2 +10*
B-2 +10*
C-3 +10*
A-3 +10*
B-3 = stiffest

 

[Reaper]

Thx Allen, is the amount of heat in the clutch normal ?

 

[Srxspec]

Never tested with the Freeride track, but on the stock track setup & stock track with 72 studs there were no clutch heat issues. Several tests of 3/4 mile wide open the whole way (98 mph on speedo) and you could hold your hand on the clutch for 8-10 seconds.

 

[Reaper]

Hmmmm, why would the track make any difference ? Did the clutch even get warm ?

98 on the speedo, holy crap never ever saw that even with the stock track with a tail wind going down a hill

What are you wrapping to on the stock track ?

BTW, I felt the clutch after like 5 miles of WOT.

 

[Srxspec]

I'm guessing increased secondary preload is the reason for higher belt/clutch temps. With the increased load the clutch will not open as easily on top end and could be slipping the belt through the secondary.

Standard kit with 180 to 220 lbs rider we run spring in stock position (A1).

Try going back to A1 (stock position) and see how RPM and clutch temps are. We want minimum of 11,100 and like to see 11,500 on prolonged wide open run (say up to 1/4 mile then should hold steady).

5 miles wide open? I'd have to buy a bulldozer and clean off some land to do that!

 

[Reaper]

Thx ! I was running on the Assiniboine river and it is a nice gentle winding river and you can hold the Phazer WOT till you run out of gas

I like to make small changes so I have changed it to B1 between my posts and will try that in same conditions and see what changes occour and then go to A1 and monitor changes. I will post results.

I will tell you this though the way it is setup now it is a cannon from 0-60mph ! I got into some really big hard drifts and it had a sweet rythm section for about a 100 meters (like a motocross track) and the sled just rocked. You would crack it on the first one and easily double it. Would not do that before, no way !

I would leave it alone but half of my riding I need to do long term WOT. I would say for snow cross a pretty sweet setting would be at C2.

 

[mlloyd]

Reaper - Where did you get your clutch kit from? How much and are any special tools required?

 

[Voda2000]

^^^ I'm cuerious too.

Does a clutch kit void warenty?

 

[Srxspec]

http://www.ulmerracing.com

Go to Performance and then Clutching then Phazer. $100 US + shipping. No special tools required and no warranty voided.

 

[Reaper]

Worth every penny

 

[BV1]

Peak HP in our machines is at 11,100 RPM as per dynotechjims dynos with and without airbox mod... if we shift out at a higher RPM then that, why dont we lose accelleration too?

From 11,100 to 11,500 we lost maybe 1-2HP and from 11,500 up it seemed to drop off pretty quickly in comparison.

Mine revs at 11,800 RPM at 135-40 km/hr on the lake and a bit lower maybe 11,500 RPM on the shift out up to that speed. I was actually thinking of putting in rivets to bring the RPM down a bit.

Curious what do u think?

-Steve

 

[Srxspec]

The reason you don't loose acceleration after 11,100 is because you're talking about 1 hp drop from 11,100 to 11,500. As you increase RPM you increase the top end MPH as well. When I saw the speedo reading of 98 mph the clutches were fully shifted out as far as they could go and the RPM had climbed to 12,100 rpm.

 

[BV1]

Thanks for the help, I have a few more questions though, Im new to the clutching / snowmobiling scene so Im trying to grasp the advantage of upgrading to a clutch kit that brings up my RPM, so dont take offense to my noob questions

1) When the clutches are fully shifted out it would be pretty hard to bring the RPM down as its basically almost direct drive at that point correct? Would any kind of clutching (without a change in gearing) affect the MPH when the clutch is fully shifted out, or is this a direct result of gearing only?

2) Let say that if for every 100 rpm off peak HP, which is 11,100 RPM, you lost 1 HP, so that you made 76 HP @ at 11,500 RPM and 76 HP at 10,700 RPM.

If your gonna shift out at 76 HP... (11,500 rpm) then wouldnt shifting out at 10,700 RPM be the exact same? At least at 10,700 RPM, when the clutches are fully shifted out (at a lower MPH speed then before due to the heavier weights etc) the machine would then approach peak HP, 11,100 rpm as opposed to run away from it.

Right?

3) I guess the point Im trying to make is why wouldnt I want to shift out at peak HP, and if I am going to shiftout higher then peak HP, how is that going to increase my top end MPH as per what you said above?

Thanks,

-Steve