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Discussion Starter #1
On the last day of the SW ride the crew and I went down to Big Springs and on the way back decide to check the top speeds on the sleds using our gps's. The county roads where very long, straight and for the most part snow covered with a few rocks thrown in. When I would run my sled up to top speed the sled would max out for a few seconds and then almost like it kicked into high gear pick up a few more miles per hr. Does anyone know what would cause this delay?

FWIW, top speed really doesn't mean that much to me as I've set this sled up for mostly offtrail play but I did manage 88mph on the gps with a 19t top gear and a 1.75 lug track :wink:
 

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the sdi system may have caused it. it may be precaution against a melt down and when it can calculate it it will run full open
 

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On the last day of the SW ride the crew and I went down to Big Springs and on the way back decide to check the top speeds on the sleds using our gps's. The county roads where very long, straight and for the most part snow covered with a few rocks thrown in. When I would run my sled up to top speed the sled would max out for a few seconds and then almost like it kicked into high gear pick up a few more miles per hr. Does anyone know what would cause this delay?

FWIW, top speed really doesn't mean that much to me as I've set this sled up for mostly offtrail play but I did manage 88mph on the gps with a 19t top gear and a 1.75 lug track :wink:[/b]
Hay Jason thats just the Flux capasitior kicking in , sounds like you need to adjust it to come in a little sooner :lmao:
Mine kicks in at 70mph and gets me to 90ish w/ 21/43 gearing turning the 136x1.5 on the SS :dazed:

:lol: :lol: I had to get the flux thing in LOL, sure you wer'nt lifting ? Sometimes blasting down a road you will lose grip and then grab. Time.. might be right about the SDI too, was it motor or seat of the paints feel? Could be a couple things, at that speed things tend to balloon(track, belt slip). If you can get a long rip agian ,take and mark your clutches w/ a felt marker to see if your under/overshifting at full out. Here's a thought.. you could be at that spot on your ramps/helix where there's a ridge at maxed out and your clutch is shifting right on that spot.What were your R,s looking like during this?.Something sliping your R's will change but if it stays the same then its in the tuning of the motor(carbs,sdi,mpem etc.). Remember your running your track loose as a goose, did it skip from ballooning?, I know your running extro's but i seen it happen with a real loose track, thats a lot of wt your turnning.ASK your dealer about it while he has it for your oppsy. Might be norm for the sdi's, could be a re-map adjustment in you MPEM. OH did you smoke a spot in your belt , this will show up at high speeds too. Hits the flat spot ,skips and grabs.
I would say it's all in what the R'S did to pin it down.

AFTER ALL.. it is a DOO , you know how these things like to fly maybe it was ready to take flight :wink:

MUTT
 

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I think what your feeling is the track catching up. There is a ton of track spin and when it finally stops it feeles like you shifted into overdrive.
Try the same long run but this time ease on the throttle all the way to wot. I bet you won't notice the afterburner affect as much.
 

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Cold pipe warming up?
Sticky clutching?
 

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I don't know what the road was like, but I often get that going across a lake. Just different amounts of resistance in the ice/snow/slush. THough if yours kicked up and then held the higher speed I doubt it's the same thing.
 

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were the engine rpms maxed the entire time? cold pipe I doubt as it should be plenty hot by the time you hit 80mph. might be able to go down more in gearing and get into the od sooner, maintaing same speed gaining low end.
 

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Discussion Starter #8
This happened during all 3 speed runs after riding for several mile so the pipe should have been nice and warm. Clutches where just cleaned at it was a new belt as I toasted the previous one the day before.

The track is pretty loose but I don't think it would be loose enough to skip. Now that its been mentioned I never did check the rpms out, next trip out I'll mark the clutches and keep an I on the rpms. Like Rick said this would tell alot.

My exhaust valves where cleaned at the start of the season but could they have any affect in this area?

My flux capasitor must not be working, isn't it 88mph and you get blasted back to the future :tongue:
 

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ya i d say it the track getting grip

when i run on the lake i can feel it give like a boost in power the best snow conditions for my sled
 

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This happened during all 3 speed runs after riding for several mile so the pipe should have been nice and warm. Clutches where just cleaned at it was a new belt as I toasted the previous one the day before.[/b]
Did you break in the new belt? Belts do have break in periods, but I don't see how that has to do with it.
 

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This happened during all 3 speed runs after riding for several mile so the pipe should have been nice and warm. Clutches where just cleaned at it was a new belt as I toasted the previous one the day before.

The track is pretty loose but I don't think it would be loose enough to skip. Now that its been mentioned I never did check the rpms out, next trip out I'll mark the clutches and keep an I on the rpms. Like Rick said this would tell alot.

My exhaust valves where cleaned at the start of the season but could they have any affect in this area?

My flux capasitor must not be working, isn't it 88mph and you get blasted back to the future :tongue:[/b]
Hay Jason, I thought of somthing that might help but I did'nt see your oppsy. By any chance is your damage bad enongh to shift anything under the hood in the motor mount area?Somthing tweaked?(clutch aligiment?). Another thing after I been thinking of this...With you running a big lug track it could just be slipping (breaking loose). You need to fill the lugs up w/ snow and have some base left for the tips of the lug to bite. What could be happening is your not fillin the lug up enough for it to bite and it breaks lose and then grabs giving you the feel of boost forward. This would show in the R'S too due to the tourqe resistance in CVT system. I did feel this a little when I was running last wk too . BUT you have a 1/4 more lug lower gearing than me and thats all it would take to make it stand out more than others. Think of it as a tire out of balance, the bigger& faster the more its noticed.
WITH these paddle tracks I noticed something about them after being on a studded low lug track. If your not filling the whole lug up so it scoops or getting a good bite with the tips in good snowpack NOT ICEY PACK, your just running on the tips(less grip, less surface contact ,SPINNING). ROAD crossings...sugar snow... icey hardpack, IT makes sense If your not getting full lug fill or good tip bite to drive you forward and are in a condition of inbetween the two (grab slip ,grab)... this is what we were riding on last wk. I felt this on the trail too , spin out the loose stuff down to the ice and then get a bite on some good base and grab.
Low gearing has a spot in this too... at high speed and low gears your tourqe to the track is higher(more addgressive, ie, stuckin 2nd wanting to go to 3rd gear ) then stock or a high gear ratio. With any gear change your shiftting/backshifting is changed to a point at high speed . With a low gear your always pulling and will take more of a load to make it backshift . UN like a high gear that will sense the lightest load change to keep you closer to O/D.
I really think if you pay attention to your R'S you will see. One of the tricks I learned on clutching and stuff is.. Go out and run a hardpack trail at high speed and dump off in the powder with NO throttle change , your R'S should move a bit and climb right back up to show your backshifting for the load change. A lower gear will take more load to change the R's.

This could be something simple as a adjustment to your clutching or it was just the conditions we had up there. I know ..another book :blush: , but I wanted to explain my reasoning, hope it shed some light on things, it sounds good anyhow :thumbsup:

OH the flux capasitior is set for 88mph for a 2500lbs car , so for our sleds you need to re-adjust for the wt ratio, works out around 68-73 mph for avg sled and rider :wink:

mutt
 

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Discussion Starter #12
More than likely it just had to be the conditions and possible track slippage, I will be my pleasure to give it another test next weekend on the RTYP trip :D
 

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I would say that since you run a 1.75" track in powder most of the time that you don't have studs? I can see maybe with just the tips of the track lugs trying to grip on hardpack that there would be an obscene amount of track spin. If so you probably just finally hooked up. I would imagine this is hard on those TALL 1.75 lugs( ripping them off). Tracks are expensive and I'm not rich, Hence my '94 sled.
 

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Discussion Starter #15
:whistling:[/b]
Two trips now and I still haven't done any full speed runs, just having too much fun playing in all the fresh powder. :wink:
 

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Discussion Starter #17
Thank`s lol[/b]
Good eye, thought you would like that better :wink:
 
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