SRX on asphalt times?

From the front view of that pic look at how much of a bend the track has.It should have a lot lower approach angle which will reduce friction.If you lower the front with about 2" of travel in the shock you will also have more track on the ground which = more traction.You theory is right about the weight transfer but if you don't have the whole track on the ground your hurting yourself.
That's what MrViper was saying about having the sled flat.
 
Thanks for explaining, that does make sense now. I did some other searches and found some info from Mr Viper 700 as well. If I'm understanding you guys correctly, try to have maximum of 2" shock travel from full compression to full extension on the ski shocks and minimize travel of, if not completely collapse and lock, the front torque arm and then adjust the rear spring/shock/transfer rods as needed to get the rails (and track) flat with the grouind.
 
I took your pic and made some colored lines on it to referance. I would personally get the track to lay more on the ground, from the pic, I see the redline marks about what you actually have biting in, and the yellow line is what you could have biting in giving you traction.
The easiest way is to take a shoplight and lay it on the concrete floor next to the sled, then go to the opposite side of the sled and lay your cheek on the floor. Everywhere you can see light under the track, your not getting traction. You want to adjust the skid so you only have about 3/8-7/16" clearance from under the drivers to the ground. The ultimate set up would be to lay the drivers and all flat but you will bend the driveshaft if you hit a good bump on return road, dont ask me how I know this...lol :o|

green lines are where the trailing arms and front suspension rods should be, they should point upward from level. You will also fine tune the spring setting once you have the rear skid sitting as flat as possible with the 3/8-7/16 airgap, just adjust the collars till its good and flat, tie it down and go racin.

to be frank, you could literally lock the rear skid solid like a dragster and get very good 60ft times on the asphalt,because the track would just stay flat and planted, you dont need transfer in a snowmobile on tar like you do a car.

Dont be suprised if you have to put the front arm completely down on the stops on the rails, it will be almost level. Youll need to remove the limiter straps and drill holes 1.5 inchs higher then stock to suck it down that far. Youll then be able to let out the straps in about 1/4 inch increments to fine tune it to your rider.

What Pro116 was saying about the front shocks is the shock springs actually help raise the frontend up more then you want on the asphalt and thats why they need to be tied down, the compressed and suddenly released energy lifts up the sled and you lose traction making for a 60ft not as good as it can be till the sled settles back down.



Like said before every 1/10th off the 60ft is 2/10ths off your ET.

its 3/4 all in the suspension , rest clutching/engine tuning
 

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WOW! There's a wealth of information! Gonna read that a few times to digest it! LOL! Sadly, I don't have time between now and Sat morning to get any of this done, but then I have a few weeks before we race again.

I really appriciate all the effort the people on this site put in, hopefully I can return some of the favors.

Thanks everyone. I'll keep you updated.
 
Working on that today and later this week. I did find that on stock Yamaha suspension, the rear axle wheels do not touch ground when sitting on a flat surface, The next forward set of wheels keeps the rear wheels about 1/8" off the ground. This allows the suspension to "rock" onto the rear wheels and next forward set under heavy acceleration and pulls about 10" of track off the ground. Today I slotted the holes for that set of wheels so now I have 4 "axles" on the ground flat. Now all I have to do is keep the chassis from lifting too much and taking the front section of track off the ground.
 
Thanks everone.

pro116, I did look into some other wheels, but didn't find any that would use the right bearing. Maybe I missed those. Also, all the ones I saw were about $30 each, didn't really want to spend that right now. Thanks though for the info.
 
Thanks prostock 700! We also ran this past Saturday (Sept 5th). I ran the sled this time (my wife had to work in VT) and was runner up (5 rounds) in the Motorcyles/Sleds eliminator. Sled ran/worked great, I was a little late with my reaction time in the final. Made 7 runs that day, 60's between 1.531-1.563, ET's 10.670-10.731. We are having a blast with this sled!
 
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