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Discussion Starter #1
I was wondering if someone could shed a little light on the top speed of their F7's. Mine is bone stock except the woody's dooly runers that i had put on it. My sled seems to top out at 88 mph. Is this just mine our has anybody else experienced this as well.

Any input anbody could give would be greatly apreciated.

Thanks
Bob aka CATPPL
 

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Mine is doing the same thing as well. It topped out at 93 and this was in 1.5 miles on a lake. Dealer told me that there is another one doing the same thing. What I find strange is that mine takes off from the line like a bullet. There has been nobody who has even come close racing me from a dead start. I will post what my dealer finds out.
 

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Valves unhooked or a defective servo motor will show these symptons. Excellent performance off the line but slugish midrange and topend performance. Take the servo cover off and see if it's cycling when the engine is started or if they are even hooked.
 

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I hit 105 with mine on Saturday and it was still pulling had to let off ran out of room... Sunday was only able to hit 95 with all the room I wanted I figured it was the tepm change cause it was warmer Sunday..Still need to check the valves F7SP
 

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Discussion Starter #9
If my valves are gummed up and need to be cleaned or my servo motor has had sex, can somebody give me some direction on how to go about cleaning them or chking to see if the motor is even working?

Thanks again

oh yeah mine does pull real hard out of the hole but is seriosly lacking in the top end department.
 

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Discussion Starter #10
If my valves are gummed up and need to be cleaned or my servo motor has had sex, can somebody give me some direction on how to go about cleaning them or chking to see if the motor is even working?

Thanks again

oh yeah mine does pull real hard out of the hole but is seriosly lacking in the top end department.
 

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I have the same problem. 98 mph is the best I’ve ever seen and that was in near perfect conditions. This weekend I first check and adjusted all of the engine stuff and then started looking at the clutches. The first thing I checked was the back pressure on the secondary. With the spring in the center hole it was at 28 pounds. I thought that was way too much. I moved the spring to the first hole and got 18 pounds. I still think that is a little high but that is as loose as it will go. I instantly gained 3mph and to my surprise it pulls a lot harder now with no back shifting problems. The next thing I checked was the belt length. My belt and my new spare were 48 3/8". My dealer said the belt should be 47 3/4" that’s a difference of 5/8". That should be good for another couple mile per hour.

For the record:

What backpressure does cat recommend for the FireCat driven clutch?

What should the length of the belt be?
 

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Originally posted by Roadwarrior@Feb 3 2003, 02:28 PM
Valves unhooked or a defective servo motor will show these symptons. Excellent performance off the line but slugish midrange and topend performance. Take the servo cover off and see if it's cycling when the engine is started or if they are even hooked.
Roadie,

When you say possible"defective" servo motor, do you mean that it is defective because it doesn't cycle at all?.... or improperly cycles?
Thanks!
-John
 

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put rear of sled on jack stand, raise engine rpm, watch for survo spool movement at 7100. should open up to full at 7100. measure free cable length, they are way to short, should be 36.5 mm. If they are not in the min-max spec window, ecm goes to fail safe at 6900. gilly
 

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Roadwarrior,

Thanks, that was the info I was looking for. I just wanted to make sure that what you meant by "defective" was that the motor would not work at all and not something like that it 'just didn't open all the way' or something like that.... I have seen mine open and close.
-John
 

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Originally posted by gillystv@Feb 3 2003, 11:40 PM
put rear of sled on jack stand, raise engine rpm, watch for survo spool movement at 7100. should open up to full at 7100. measure free cable length, they are way to short, should be 36.5 mm. If they are not in the min-max spec window, ecm goes to fail safe at 6900. gilly
gillystv,

I have seen my F7's move on the jackstand at, like you said, right around 7000 RPM's(kinda hard to tell when the hood is open and you are trying to watch the spool ;) ..)

That's interesting what you say about the min/max. cable lenght and the fail safe mode. At first I was wondering how too short of cables(seems many were this way from set-up/factory) could possibly affect the top end MPH of these sleds but....... If the sled goes into fail-safe mode at 6900 RPM's because the cable were adjusted too short, then it makes perfect sence why some sleds might be lacking the top end speed. Am I following correctly?? Thanks!
-John
 

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gillystv,

One other thing I wanted to ask you about the movement of the servo motor. I noticed when I had it on the stand and hit the RPM's that would make the servo activate and open that it was a EXTREMELY FAST/QUICK motion of opening and closing..... Is this the normal cycle/motion of the servo motor?? Thanks!
-John
 

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hey guys i've seen 115 on my f-5 standard stock and i dont know if i should believe it some one in maximum sleds said theirs hit 115 too and the way he kept fighting back sounded like it was true..how accurate are these things? i looked to the side and seemed like i was doin the speed but im not sure.
 
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