srx 500 ft race ?s

mrviper700 said:
what secondary spring ya using?
Also is it pulling the ski's more then a 6-8inchs on the start?

what rpm does it come out of the hole at?? and whats the tach do rev up to 8100 or sp rpm, then come out and overshift?, meaning the tach drops rpm for a brief second then picks rpm back up, what rpm does it cross the finish at?
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Thanks for the quick reply! Iam using a green spring.It pulls the skis 6-8 inches out of the hole.I never looked to see what rpm it was comeing out of the hole I was to busy holding on to look!I will take it back out for a nothere pass and look.It does rev up to about 8100 or so and overshift .I think when i crossed the line it was 8300-8400 .But Iam going to go back out and test it again and I will keep a closer eye on the rpms . before I do this I will set the secondary at 90. I will repost with the results
 

Iset the secondary at 90 and try it again and it come out of the hole about 7200 -7400 then climbs quickly to 8000 and about 8300 at the 500ft mark.
 
is the belt deflection set tight, meaning it will sit there and squeel like a pig at idle? if it doesnt, set it tight the belt should be riding out of the secondary clutch about a good 1/8th inch, all the little raised cogs need to be above the edge of the secondary sheave, this will improve the holeshot and take out some of the low rpm, as if the deflection is too much your shifting it up into a higher gear too fast. Kinda like starting off in 2nd gear or 3rd gear in a stick shift car.

you adjust this by the little washers on the back of the secondary, will be 3 little 8mm headed bolts, add washers spacing out the bolt, this will move the sheaves closer together and raise the belt up.
 
I had an over shift on My MTN SRX when testing for the snow drags. I fixed this by going up to a white secondary at 70. I really think you are going the wrong way by increasing your secondary tension. That amount of tension is excessive for drag racing.

What are you running in your primary? You running something soft? I ran an extremely stiff spring and shims which gave me great results.
 
Thanks guys! I think I got her dialed in pretty good right now. My skies were coming up to high which was taking to much track off the ground causing it to up shift to quick. After setting the suspension up better and adding some washers to the secondary, it is coming out of the hole at about 8300 and drops back to about 8000 and crossing the 500 at 8200 -8300. I will be racing tomorrow, and I will let you all know how I make out.
 
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schinner16 said:
so how did ya do??
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well I ended up 4th in the improved. not good.But we all had fun and thats the main thing!I will try to better my sled for this weekend some of us are going up to my feild this Sat to race around a bit. There was a wicked fast viper there he was doing well. I also raced my buddys vector and got second in 4 class.
 
whoa....improved class? thats a trail stock set up that i gave you, from going from your original post I didnt see where it was a improver, what kinda times were you running? most improved times are 5.2-5.3 in 500ft.
 
mrviper700 said:
whoa....improved class? thats a trail stock set up that i gave you, from going from your original post I didnt see where it was a improver, what kinda times were you running? most improved times are 5.2-5.3 in 500ft.
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I also ran in the stock class and didnt do as good .I think I placed 5th.When I went in the improved I put my mrpb can on and adjusted my transfer rods and its funny I was beating sleds that were beating me in stock.There was no time clock so Iam no sure what the time was. mr. viper can you give me a set up for improved?
 
Blue Devil,

How bad are you getting beat and where at? Top end or out of the hole? What set-up do you have exactly? Unless there are alot of F-7's there, you shouldnt be placing so bad.
 
tomseal6 said:
Blue Devil,

How bad are you getting beat and where at? Top end or out of the hole? What set-up do you have exactly? Unless there are alot of F-7's there, you shouldnt be placing so bad.
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Iwas getting beat by 3-4 lenghs. they seem to get me right out of the hole and gain some more on me at the end. This is what I am running 8bu-00 4.5 in the tip and .8 in the center 52/42 green spring and 20/39 gearing.
 
seriously,

thats why I used the 19/40 gears. I never got beat out of the hole unless the other guy was going to win no matter what... need to get your engagement up to around 5000 RPMs
 
IMO, you are geared for 660 feet.

You have the carb needles pulled all the way up? clip on bottom groove? you have to cause you are slamiing the motor in full fuel position for drag racing and the fuel has to be there. Motor will slightly hesitate otherwise but it is plenty enough time for you to lose. There is very very little margin for error in 500 feet.
 
1.) your sleeping on the tree?

2.) the sled either spins too much or overshifts on the start, rooster tail of dirt on take off?

3.) you dont have enough belt deflection or the primary spring needs more pressure, whats the engagement speed right now?

4.) topend problems- secondary clutch wound too tight, chaincase chain tension too tight.


Also, if you can take a pic of the sled sitting on your garage floor, i can tell if the skidframe is adjusted close or not.
 
i have a 02 viper with bender pipes and cant get it to stay on rpm's what is a good set up for it
 
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