[Cliff Randall]

Hi guys.......The hunter has once again entered the forest. I've begun my assault on the Mach suspension looking for that elusive extra 10mph.
I've attached a couple of pics that indicate the obvious restriction at the rear wheels and the reason that BPR probably only used 7 1/2" idlers on this sled in the first place. Remember larger rear wheels means a smoother transfer and less therefore less resistence. Look closely at the inner rear roller wheel and you'll see that if it were any bigger (especially upon suspension compression) it would hit the frame bar. The second pic (to follow) shows where the wheel sits if a longer track were used and the axle adjusters pushed out to max, not that you would do this because you'd have no adjustment capability to tighten the track, however for demonstration purposes this is what it would look like to allow larger wheels. My thought is to design a 9-10"wheel system that I think can be done with mimimum machining and cost - stay tuned for this and other suspension mods as I search for that magic 140mph............Cheers,
Cliff

Attached File(s)

•  Rear_wheels__1.jpg (42.06K)
  Number of downloads: 96

[Cliff Randall]

Next pic with adjuster back as far as it will go, note the clearance.
Cliff

Attached File(s)

•  Rear_wheels__2.jpg (38.09K)
  Number of downloads: 73

[subiwrx]

Most of the speed guys use a 128x13.5 track; they have to extend the lenght of the rails at the rear and , doing so, install oversize wheels at the same time...

[CELLARDWELLER]

Cliff;
I'm working on a similar project, but on a triple. The large rear idlers are the way to go, without a doubt. The "Wahl" rear looks like a good roller setup......... 128" track would put the rear wheel back farther and leave room for big guns.......? I'm seeing where you decide to go:) Tried to attach the "wahl" picture, but not working;(

[Cliff Randall]

My goal is to match up the OD of my Summit sprockets (best mod I ever did to this monster, I get 0 track slippage) pic attached, which are 9.5". I will install a longer track when this is mod is complete - more pics to follow.
Cliff

Attached File(s)

•  Wheel_mods__3.jpg (41.15K)
  Number of downloads: 62

[Cliff Randall]

Doo lovers...........Anybody local want my old track? I shaved it down by 1/4" to approx 3/4? I can give you the studs but I need the backers and bolts.
Cliff

[Cliff Randall]

Pic of track.
Cliff

Attached File(s)

•  Old_track.jpg (44.15K)
  Number of downloads: 56

[1019revagade]

Pic of track.
Cliff

I don't know how to go fast,but most people I talk to say the extrovert drivers take away a lot of speed...some lathe or grind the extros off claiming they still drive well....

What's under the car salesman's sled? He talks really fast....lol

[Cliff Randall]

Thanks Sub, but I can't pull my taller gearing without the Summit sprockets. I tried with stock drivers but the racheting was horrible. If I cut the Summits down I'd be afraid I'd lose the high speed effectiveness as the track balloons and gets out past the sprocket end.
Cliff

[SKIDOOCHRIS]

cliff
if you use a 128 track and 9-10 rear wheels you will need to extend the snow flap too
you can find rail extener kits but they wont take the BIG wheels
another high speed trick is use 147mm wheels stock are 140mm less hyfax melt
they were stock on some sleds
they are the best for grass drags
http://www.alternativeimpact.com/BIG_WHEEL_KITS.htm

[N1DE3]

CLIFF ARE GOING TO SELL THOSE LIGHTWEIGHT WHEELS THAT ARE ON THE SLED NOW.
LET ME KNOW IF YOU ARE.
THANKS STEPHEN

[Cliff Randall]

Thanks Chris, exactly what I want wheel wise, then I'll machine up some frame extenders and bolt them or weld them in place. I'm 2 weeks away from figuring this one out!.....No problem on the snow flap extension, piece of cake.
Cliff

[REDLINE 1]

Cliff,

I have 9" rear idlers on my 05 (no rail extentions) . Mountian Machines sells a freedom axle set up. You run two 9"s on the outside and 1 or 2 7 1/4" wheels inside the rails. The stock rear idlers on my 05 are 180mm or approx 7 1/16". I'm running the billet 9" on the outside but I'm thinking of changing to 9" carbon. I want to run studs in the outer belts and the billet does not have any rubber on them so they get chewed up pretty bad.

Attached File(s)

•  IMG_1371.JPG (44.18K)
  Number of downloads: 52

[Cliff Randall]

Cool Red, thanks.........With 300hp on tap I'm afraid I'd buckle the track if I used smaller wheels in the center. It is imperative that my wheel set-up be consistant across the axle. I will be looking for CF wheels as well or some 9 1/2" rubber covered units as I plan to run 192 studs in order to hook this baby up out of the hole.
Cliff

[Cord]

I'm a professional bench racer, I really know what I'm talking about.

Are you still running the slides (hyfax)? At these high, dry track speeds the slides have to be heating up. I'm wondering if maybe at the higher temps the slides are adding extra drag. Has anybody tried running extra wheels and taking the slides off? If you don't take the slides off, then how about applyinig some silicone spray to the slide to help lubricate them?