Track speeds

[TreeThrasher]

On a powder hill what kind of track speeds are you guys seeing on your Axys? These sleds seem to do quite well without tremendous speeds.

Please list conditions, elevation, track on ax and any modifications

Thanks!

 

[Sheetmetalfab]

On a powder hill what kind of track speeds are you guys seeing on your Axys? These sleds seem to do quite well without tremendous speeds.

Please list conditions, elevation, track on ax and any modifications

Thanks!

163x3 slp pipe 2000' elevation. 2' of fresh snow, solid 8350 rpm 45 mph trackspeed.
Ethanol mode.
A2d sledworks clutching

 

[TreeThrasher]

Thanks!

Mine is similar to that until it goes into a giant wheelie...then it comes up to about 50...

I had a tad too much weight last ride and up to about 5k feet I had 8200 and mid to upper 40s. Over 5k feet rpm went to 8k and speed fell a bit as well

 

[NoSoup4U]

The problem with comparing track speed is that conditions vary so widely from day to day and area to area. Also, a big variable is what is your ground speed at the time you are measuring the track speed. Ground speed of 20 mph is going to have a significantly higher track speed than barely moving just before turn out. Anyway, this is what I typically see:

163x2.6 track
SLP pipe and clutching
8300-8400 RPM
8500 ft elevation
Steep climb in untracked powder that is not particluarly dry or wet
5 MPH ground speed
36-37 MPH track speed

 

[TreeThrasher]

I completely agree with speeds varying hugely with conditions and other variables. I'm mainly looking to form a general cross section of information.

Nosoup what kind of speed do you see out of your sled lower down the hill while you still have ground speed?

Anyone have any side by side comparison with slp pipe and bikeman pipe?

Turbos? Drop in kits? Stage kits? Big bores?

Thanks!

 

[die hard poo]

When my sled was running right:
Axys 155x3"
Rider weight:185# no gear
0-3000ft
SLP Pipe/Can
MTX 76g Weight
SLP Blue/Pink Primary Spring
Stock secondary with derlin washers

47-50mph in untracked dryish snow
Heavy mash potato snow 43-47mph

 

[Teth-Air]

The problem with comparing track speed is that conditions vary so widely from day to day and area to area. Also, a big variable is what is your ground speed at the time you are measuring the track speed. Ground speed of 20 mph is going to have a significantly higher track speed than barely moving just before turn out. Anyway, this is what I typically see:

163x2.6 track
SLP pipe and clutching
8300-8400 RPM
8500 ft elevation
Steep climb in untracked powder that is not particluarly dry or wet
5 MPH ground speed
36-37 MPH track speed

This one is closest to mine although I have been only turning 8150 RPM with the latest clutching. Lightening the primary actually made me lose tack speed so be careful not to only look at RPM when doing your clutching.

 

[steepndeep800]

155 2.6 Diamond S can, Carls Clutching 9000-9500 ft
36-38 mph 8200-8300 rpm
medium snow weight untracked
pretty happy over all put SLP pipe on next and adjust clutching see what happens.

 

[snobyrd]

163x3 slp pipe 2000' elevation. 2' of fresh snow, solid 8350 rpm 45 mph trackspeed.
Ethanol mode.
A2d sledworks clutching

Are these speeds from running at a hill with lots of room to get your speed up or are these immediate track speeds as soon as you pin the throttle.
I havent had a chance to poke at a big hill,only tight creek beds where holding open the throttle for more than 20 seconds, i see 39 mhp consistently with heavly loaded bikeman weights,69.1 grm, with all stock clutching.
One thing i noticed is, the hotter the pipe gets,the more power it makes, thus reason why poking at a big hill for more than 25 seconds pulls better track speed and power.
4000 feet
165 lbs in jeans
155 2.6

 

[2005 1m]

155 2.6 Diamond S can, Carls Clutching 9000-9500 ft
36-38 mph 8200-8300 rpm
medium snow weight untracked
pretty happy over all put SLP pipe on next and adjust clutching see what happens.

I'm almost identical to you...

163 x 2.6 with only a Diamond S can and Carl's clutching (62-42-40 helix currently, 60 gr EPI weights, roller bearing). Apprx 9500 ft, light Utah powder, and I weight about 175 before gear.

On a big, long hill with about a 50 yard run in I'm settling in at only about 8,050 RPM but I'm pulling the same track speeds of 36-38 mph. On the trail if I nail it the RPMs will jump to 8200 but settle back down to 8100 or even 8050. In talking to Carl's today I am going to try switching to the secondary helix setting of 60-40-40 to see if that helps pull up the RPMs a bit. I think/hope there is a little more to be had in this setup.

 

[snobyrd]

This one is closest to mine although I have been only turning 8150 RPM with the latest clutching. Lightening the primary actually made me lose tack speed so be careful not to only look at RPM when doing your clutching.

I did some testing on a lake with runs about 15 seconds long, secondary was stock, i tried epi 64 grm and 64 stock with a gold spring and track speeds between 73 and 75 mph, i tried bikeman with 66 grm 69.1 and slp 71 grm all with stock blk prim spring and i saw high 70s for trax speed at 8100 to 8250 rpm.
I think this motor likes to be worked hard to get the most out of it.
I also did notice , my 2nd run up the lake back to my staging area with the pipe being hotter, the rs and moh were slightly better.

 

[Sheetmetalfab]

Are these speeds from running at a hill with lots of room to get your speed up or are these immediate track speeds as soon as you pin the throttle.

I havent had a chance to poke at a big hill,only tight creek beds where holding open the throttle for more than 20 seconds, i see 39 mhp consistently with heavly loaded bikeman weights,69.1 grm, with all stock clutching.

One thing i noticed is, the hotter the pipe gets,the more power it makes, thus reason why poking at a big hill for more than 25 seconds pulls better track speed and power.

4000 feet

165 lbs in jeans

155 2.6

10-15' run in.
Steep in the trees
5-10 mph ground speed.
Hit an open patch and look down for a sec.

https://vimeo.com/152515844

Some wide open spaces.
Today......

Sent from my iPhone using Tapatalk

 

[Crazyj700]

All track speeds need to be measured at low ground speeds like 5-10 mph when almost stuck. Or stop facing uphill where you know you can barley take off without getting stuck and see what your speeds are then. 5-10 second pulls

 

[kanedog]

When my sled was running right:
Axys 155x3"
Rider weight:185# no gear
0-3000ft
SLP Pipe/Can
MTX 76g Weight
SLP Blue/Pink Primary Spring
Stock secondary with derlin washers

47-50mph in untracked dryish snow
Heavy mash potato snow 43-47mph

Interesting that these speeds are different than the others.

 

[Gunk]

just road in 18in of fresh light powder, slowly setting up to a medium weight powder, all i can say is this new set up , engine , track, chasis, it needs more track speed. its realy the only thing holding me back from high marking both turbos i was riding with. and im only talking 20ft

 

[die hard poo]

Interesting that these speeds are different than the others.

I ride at 0-2000ft most of the time in the mountains, plus Alaska has really dense air so we make more power in our riding area. It is a blessing and a curse cause anything other than a pipe and your sled won't run right with turbos/big bores... Trust me, I have dabbled in just about everything trying to get something to run right here.

 

[kanedog]

I hear ya. Coastal air is a different animal. There is no in between. It has to run good or its gonna run bad. It sounds retarded to say it like that but that what it is!

 

[TreeThrasher]

Ya. One thing I have really noticed is that the Axys is nasty in dense air. You can see the trend with what guys are posting for track speeds here...big numbers are coming from guys down in altitude. Mine seems to really slow down up high. It's something we will be working hard on

 

[Sheetmetalfab]

Ya. One thing I have really noticed is that the Axys is nasty in dense air. You can see the trend with what guys are posting for track speeds here...big numbers are coming from guys down in altitude. Mine seems to really slow down up high. It's something we will be working hard on

It's mathematical.
Watching videos of pump gas+ turbo's at 10000' I think my sled runs similar. Obviously a turbo at low elevation will rip.
I have no desire to have the turbo "issues".
Race gas
Plugs
Tuning
Rebuilds
Melting chit.
Reeds

My sled runs soo good it makes me giggle inside the helmet.
Riding with some pro's a m1100t a m800 proclimb and they all can barely touch the hills i can carry speed over the top.
Separates the men from the boys.

 

[TreeThrasher]

No doubt, 3 percent per 1000 feet is the general rule. I just feel like maybe the axys doesn't deal with elevation gain as well as my doo. Port size may have something to do with it. Not sure yet.