I decided to take our 1995 ZRT 800 to a speed run today. The sled is basically stock, with the exception of the Reichard's pipes/stingers. It has 192 trail studs (which did not help that much).

I have the carbs dialed in ok, as the plugs seem just about right, but I feel my clutching is where the sled is lacking.

I started with a purple primary spring, 54g weights, a yellow secondary spring, and a 62/52 helix. The secondary spring was set in the middle hole.

My first run was 101.58, which I thougt was ok. Lots of other sleds were running in the mid to high 90s--mxz 700/800s, Polaris 800's, SRX 600/700s, etc. Those with more experience/better set up sleds were running closer to 110, and the big boys all the way up to 170+.

My second run sucked. The sled only pulled 75mph, and it did not rev past 7200 rpm. I looked everything over, and everything looked good, so I tried again......78mph. I pulled the secondary cover, shifted one hole to the right, and tried it again. 79mph WTF?

I talked to a few others there, and decided to put a yellow/green primary in. So I pulled the clutch, and did the swap. I ran 102.58, which was my best for the day.

I know that is not a very impressive number, but I think the sled has more left if I can clutch it right.

Does anyone have any recommendations on what the hell may have happened on the middle runs? If the sled hits 8500+ rpm it pulls like crazy, but those middle runs it just would not rev. I checked the plugs, and even threw in another set after the second flop run, and nothing. The sled never sputtered, and always seemed to be running on all three.

I have a non-roller secondary, and was wondering if a roller would help? I did notice that just about everyone doing over 100mph had a lift for their sleds. They brought it to the line, raised their sleds, and reved them up for a few seconds to clear them out. Am I missing something there as well?

Any words of wisdom would be greatly appreciated.

Hope for snow.

--Monza

102 is right on the range for a trail studded machine that is not setup for speed. your rear skid has a lot of speed in it. meaning playing with how weight is transfered and how the machine rides down the ice.
you are geared to low, to much helix, not enough wieght in the primary, engagement should be as low as possible, or atleast soft so you dont snap out of the hole. front ski shocks springs lowered alot. make note of rpm and speed and how the machine felt after each run. and only make one change at a time.

for the bog maybe your slides in the secondary are on the worn side. sounds like you punched it and she spun but the clutching couldnt backshift and you got a bog. or your primary spring just happen to take a crap on you after the first run.

my very first run with my stock 800 was 101 mph I almost flipped over backwards and was all over the track, i didnt have a good rear skid setup for the amount of traction i had. after that in about 15 more runs down the track i was up to 108 mph.