Speeds?

[yamiboost]

What kind of speeds are you guys seeing on your boosted apex mtx in the 10-14psi range? Im running 162x15x2 1/4 track and 23 39 gearing.(This is at sealevel btw) We have races here this coming weekend and i know this thing isnt gonna hit no great top end im more looking forward to the drags but i was kind of hoping to see 100mph anyway... Was out yesterday playing with clutching and was only hitting 94mph radar in 1000'. This was in +7*c temps and about 4-6'' of wet snow. It pulls hard out of the hole seen 85mph radar in 500'. Anyone else running this big of gearing in their apex? i do have a 24t gear i can throw in but by useing the gearing calc at the top of the page i should beable to pull 100+mph with what i have.

 

[mulot30th]

TWO weeks ago:

My turbo mtx apex with a 174" paddle track running 14 psi of boost, 9200 rpm (yes 9200 rpm, because it was clutched for 20+psi of boost but I had major boost leak...) so it was no fast at all for what it is and did not felt fast either.

600ft hilldrag race I was getting to 90-91 mph during practice passes, similar snow and temperature that you are describing too.


If that can help you

 

[yamiboost]

It seems like im running out of gear little over half way down the track but if im using the gearing calc right i should hit more than 94mph with 23 39 gears??? rpms go right to 10600 at the start then back to 10000 maybe a shade under then works its way to 10400 and stays there. I kno im under reving a little but it should be pretty close when it cools down later the week i wouldnt be surprised if i have to ad another washer or so to keep off the limiter. I am far from a pro when it comes to clutching lol i tried moving a little more weight to the tip but it made my rpm to high at start off and i was under reving on top end. I have a few primary springs (mpi sent me when we were trying to get my attak clutched in) but i dont kno what is firm and what is soft when it comes to the colors... the one in there now has 3 pink marks on it, is there anywhere on the site that tells what the different colors mean?

 

[mulot30th]

my sled being a mountain sled much more than a drag sled, it is geared for powder riding. Clutching is also good for powder riding more than drag racing, I always use strait angle helix on this sled (not so good for drag racing)

107mph is my current top speed at 11000rpm but I can saw over 115mph a couple times only because my revlimit is now at 11800

 

[Riceburner]

It seems like im running out of gear little over half way down the track but if im using the gearing calc right i should hit more than 94mph with 23 39 gears????

I am sure in those conditions with that temperature you are losing at least the 6 mph you think you are missing by not getting all the power to the "ground".

Even with your deep lug track you are losing a lot of power to that soft wet snow at 7 C.

 

[yamiboost]

It seems like im running out of gear little over half way down the track but if im using the gearing calc right i should hit more than 94mph with 23 39 gears????

I am sure in those conditions with that temperature you are losing at least the 6 mph you think you are missing by not getting all the power to the "ground".

Even with your deep lug track you are losing a lot of power to that soft wet snow at 7 C.

Looks like temps are gonna be in the -5 to -10 range the weekend so hopefully that will make all the difference.

 

[hlmrx1]

What kind of speeds are you guys seeing on your boosted apex mtx in the 10-14psi range? Im running 162x15x2 1/4 track and 23 39 gearing.(This is at sealevel btw) We have races here this coming weekend and i know this thing isnt gonna hit no great top end im more looking forward to the drags but i was kind of hoping to see 100mph anyway... Was out yesterday playing with clutching and was only hitting 94mph radar in 1000'. This was in +7*c temps and about 4-6'' of wet snow. It pulls hard out of the hole seen 85mph radar in 500'. Anyone else running this big of gearing in their apex? i do have a 24t gear i can throw in but by useing the gearing calc at the top of the page i should beable to pull 100+mph with what i have.

You don't mentin what driver's you are using? If you have 8 tooth, you are probably running out of gear at 1000', and maybe digging a tunnel at the start. What distance are you running, 1000'? Uphill or flat. You're 500' sounds pretty good and your rpms sound good too.

 

[yamiboost]

Im runing 7 tooth avid drivers. I was testing at 1000' but the track will be 1/4mile and drags 1000' on the flat. I was out today and the snow is a little harder and i was hitting the rev limiter, im gonna ad a couple grams to the mid tomorrow and see if my top end went up if not im def running out of gear.

 

[hlmrx1]

Where you hitting the rev limiter, on the top or at the start? With 7 tooth drivers and your gearing according to my calc (ulmer's I believe) you'll top out at around 100 mph at 10500 rpm. I would go with 25/38 gearing for that kind of run. I know asphalt is different, but I was running that gearing with 10 tooth drivers in the 1/4 mile. That gearing with 7 tooth should give you 107 or a little higher and it may not be enough, although your pulling a different track than I am. You may not need to change your clutching then.

 

[yamiboost]

I was hitting the limiter on the start and almost at 11000 on top i was thinking id ad some weight to the mid? seeing im happy with the shift. I dont have a 25t gear 24 is the biggest i have but i do have a 38. Spose to find out tomorrow if the races are going ahead saturday forsure, looks like were gonna have to find a new location there is very little snow left on the bay and temps are in the + again today but spose to drop to -12 tonight and -19 tomorrow. If they dont go ahead me and my friends are spose to head to the mountains saturday so ill need my gearing kept the way it is for that. Almost every year we have the races here i wished i had a paddle track cause the race track was all soft snow and my attak just dug a grave even with 1.5'' lug and now this year im ready for the snow its all hard last raceday my attak ran 106mph and got 1st place a mcx apex came in second with 101mph and a mach z 3rd at 100mph that was in soft snow this is gonna be weekend for the shorttracks.

 

[hlmrx1]

What kind of weights are you running? I think you need to add weight in the heel if your hitting the limiter off the line. I think I'd go with the 24/38 if that's all you have.

 

[yamiboost]

I have STM supertips 60y base. I think the heel is full(1t & 4 washers) guess ill have to get more pucks if i wanna put more in the heel. Ill double check tomorrow and see what is in the heel forsure i never touched the sled today but on the bright side ITS SNOWING The more snow the better when ur running a paddle track. I was tempted today to cut down my old maverick track to 1 1/4'' and put that on but figured it wasnt worth the fooling around for one day.

 

[mulot30th]

I have STM supertips 60y base. I think the heel is full(1t & 4 washers) guess ill have to get more pucks if i wanna put more in the heel. Ill double check tomorrow and see what is in the heel forsure i never touched the sled today but on the bright side ITS SNOWING The more snow the better when ur running a paddle track. I was tempted today to cut down my old maverick track to 1 1/4'' and put that on but figured it wasnt worth the fooling around for one day.

All people were telling me to cut my paddle track too when I raced my monutain sled .. Not worth it for a single racing day....

 

[yamiboost]

I have STM supertips 60y base. I think the heel is full(1t & 4 washers) guess ill have to get more pucks if i wanna put more in the heel. Ill double check tomorrow and see what is in the heel forsure i never touched the sled today but on the bright side ITS SNOWING The more snow the better when ur running a paddle track. I was tempted today to cut down my old maverick track to 1 1/4'' and put that on but figured it wasnt worth the fooling around for one day.

All people were telling me to cut my paddle track too when I raced my monutain sled .. Not worth it for a single racing day....

I have my old maverick track its in good shape but the lugs are all bent over, cutting the lugs down would be the only way to make use of the junk. I cut a 1/2'' off the maverick 153'' nyrto track made a world of difference in every snow condition. I like the look of the new 2012 nytro track i might give that one a try next winter.

 

[mulot30th]

I have STM supertips 60y base. I think the heel is full(1t & 4 washers) guess ill have to get more pucks if i wanna put more in the heel. Ill double check tomorrow and see what is in the heel forsure i never touched the sled today but on the bright side ITS SNOWING The more snow the better when ur running a paddle track. I was tempted today to cut down my old maverick track to 1 1/4'' and put that on but figured it wasnt worth the fooling around for one day.

All people were telling me to cut my paddle track too when I raced my monutain sled .. Not worth it for a single racing day....

I have my old maverick track its in good shape but the lugs are all bent over, cutting the lugs down would be the only way to make use of the junk. I cut a 1/2'' off the maverick 153'' nyrto track made a world of difference in every snow condition. I like the look of the new 2012 nytro track i might give that one a try next winter.

Okay not quite same situation, my track is almost brand new lolllllllll